moodle/lib/dmllib.php
stronk7 6c279afaef Now all the get_records() functions support only one field
to be specified in the SELECT clause. Not needed anymore to
write double "SELECT id, id..." queries. Results returned
follow exactly the same structure than normal recordsets
(first field = key) MDL-5877

Merged from MOODLE_17_STABLE
2006-11-04 17:01:34 +00:00

2047 lines
79 KiB
PHP

<?php // $Id$
///////////////////////////////////////////////////////////////////////////
// //
// NOTICE OF COPYRIGHT //
// //
// Moodle - Modular Object-Oriented Dynamic Learning Environment //
// http://moodle.com //
// //
// Copyright (C) 2001-3001 Martin Dougiamas http://dougiamas.com //
// //
// This program is free software; you can redistribute it and/or modify //
// it under the terms of the GNU General Public License as published by //
// the Free Software Foundation; either version 2 of the License, or //
// (at your option) any later version. //
// //
// This program is distributed in the hope that it will be useful, //
// but WITHOUT ANY WARRANTY; without even the implied warranty of //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //
// GNU General Public License for more details: //
// //
// http://www.gnu.org/copyleft/gpl.html //
// //
///////////////////////////////////////////////////////////////////////////
/// This library contains all the Data Manipulation Language (DML) functions
/// used to interact with the DB. All the dunctions in this library must be
/// generic and work against the major number of RDBMS possible. This is the
/// list of currently supported and tested DBs: mysql, postresql, mssql, oracle
/// This library is automatically included by Moodle core so you never need to
/// include it yourself.
/// For more info about the functions available in this library, please visit:
/// http://docs.moodle.org/en/DML_functions
/// (feel free to modify, improve and document such page, thanks!)
/// GLOBAL CONSTANTS /////////////////////////////////////////////////////////
$empty_rs_cache = array(); // Keeps copies of the recordsets used in one invocation
$metadata_cache = array(); // Keeps copies of the MetaColumns() for each table used in one invocations
$record_cache = array(); // Keeps copies of all simple get_record results from one invocation
$record_cache_size = 0; // Count of get_record results stored in this invocation
/// FUNCTIONS FOR DATABASE HANDLING ////////////////////////////////
/**
* Execute a given sql command string
*
* Completely general function - it just runs some SQL and reports success.
*
* @uses $db
* @param string $command The sql string you wish to be executed.
* @param bool $feedback Set this argument to true if the results generated should be printed. Default is true.
* @return string
*/
function execute_sql($command, $feedback=true) {
/// Completely general function - it just runs some SQL and reports success.
global $db, $CFG;
$olddebug = $db->debug;
if (!$feedback) {
$db->debug = false;
}
$empty_rs_cache = array(); // Clear out the cache, just in case changes were made to table structures
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
$result = $db->Execute($command);
$db->debug = $olddebug;
if ($result) {
if ($feedback) {
notify(get_string('success'), 'notifysuccess');
}
return true;
} else {
if ($feedback) {
notify('<strong>' . get_string('error') . '</strong>');
}
if (!empty($CFG->dblogerror)) {
$debug=array_shift(debug_backtrace());
error_log("SQL ".$db->ErrorMsg()." in {$debug['file']} on line {$debug['line']}. STATEMENT: $command");
}
return false;
}
}
/**
* on DBs that support it, switch to transaction mode and begin a transaction
* you'll need to ensure you call commit_sql() or your changes *will* be lost.
*
* Now using ADOdb standard transactions. Some day, we should switch to
* Smart Transactions (http://phplens.com/adodb/tutorial.smart.transactions.html)
* as they autodetect errors and are nestable and easier to write
*
* this is _very_ useful for massive updates
*/
function begin_sql() {
global $db;
$db->BeginTrans();
return true;
}
/**
* on DBs that support it, commit the transaction
*
* Now using ADOdb standard transactions. Some day, we should switch to
* Smart Transactions (http://phplens.com/adodb/tutorial.smart.transactions.html)
* as they autodetect errors and are nestable and easier to write
*/
function commit_sql() {
global $db;
$db->CommitTrans();
return true;
}
/**
* on DBs that support it, rollback the transaction
*
* Now using ADOdb standard transactions. Some day, we should switch to
* Smart Transactions (http://phplens.com/adodb/tutorial.smart.transactions.html)
* as they autodetect errors and are nestable and easier to write
*/
function rollback_sql() {
global $db;
$db->RollbackTrans();
return true;
}
/**
* returns db specific uppercase function
* @deprecated Moodle 1.7 because all the RDBMS use upper()
*/
function db_uppercase() {
return "upper";
}
/**
* returns db specific lowercase function
* @deprecated Moodle 1.7 because all the RDBMS use lower()
*/
function db_lowercase() {
return "lower";
}
/**
* Run an arbitrary sequence of semicolon-delimited SQL commands
*
* Assumes that the input text (file or string) consists of
* a number of SQL statements ENDING WITH SEMICOLONS. The
* semicolons MUST be the last character in a line.
* Lines that are blank or that start with "#" or "--" (postgres) are ignored.
* Only tested with mysql dump files (mysqldump -p -d moodle)
*
* @uses $CFG
*
* @deprecated Moodle 1.7 use the new XMLDB stuff in lib/ddllib.php
*
* @param string $sqlfile The path where a file with sql commands can be found on the server.
* @param string $sqlstring If no path is supplied then a string with semicolon delimited sql
* commands can be supplied in this argument.
* @return bool Returns true if databse was modified successfully.
*/
function modify_database($sqlfile='', $sqlstring='') {
global $CFG;
if ($CFG->version > 2006101004) {
debugging('Function modify_database() is deprecated. Replace it with the new XMLDB stuff.', DEBUG_DEVELOPER);
}
$success = true; // Let's be optimistic
if (!empty($sqlfile)) {
if (!is_readable($sqlfile)) {
$success = false;
echo '<p>Tried to modify database, but "'. $sqlfile .'" doesn\'t exist!</p>';
return $success;
} else {
$lines = file($sqlfile);
}
} else {
$sqlstring = trim($sqlstring);
if ($sqlstring{strlen($sqlstring)-1} != ";") {
$sqlstring .= ";"; // add it in if it's not there.
}
$lines[] = $sqlstring;
}
$command = '';
foreach ($lines as $line) {
$line = rtrim($line);
$length = strlen($line);
if ($length and $line[0] <> '#' and $line[0].$line[1] <> '--') {
if (substr($line, $length-1, 1) == ';') {
$line = substr($line, 0, $length-1); // strip ;
$command .= $line;
$command = str_replace('prefix_', $CFG->prefix, $command); // Table prefixes
if (! execute_sql($command)) {
$success = false;
}
$command = '';
} else {
$command .= $line;
}
}
}
return $success;
}
/// GENERIC FUNCTIONS TO CHECK AND COUNT RECORDS ////////////////////////////////////////
/**
* Test whether a record exists in a table where all the given fields match the given values.
*
* The record to test is specified by giving up to three fields that must
* equal the corresponding values.
*
* @uses $CFG
* @param string $table The table to check.
* @param string $field1 the first field to check (optional).
* @param string $value1 the value field1 must have (requred if field1 is given, else optional).
* @param string $field2 the second field to check (optional).
* @param string $value2 the value field2 must have (requred if field2 is given, else optional).
* @param string $field3 the third field to check (optional).
* @param string $value3 the value field3 must have (requred if field3 is given, else optional).
* @return bool true if a matching record exists, else false.
*/
function record_exists($table, $field1='', $value1='', $field2='', $value2='', $field3='', $value3='') {
global $CFG;
$select = where_clause($field1, $value1, $field2, $value2, $field3, $value3);
return record_exists_sql('SELECT * FROM '. $CFG->prefix . $table .' '. $select);
}
/**
* Test whether any records exists in a table which match a particular WHERE clause.
*
* @uses $CFG
* @param string $table The database table to be checked against.
* @param string $select A fragment of SQL to be used in a WHERE clause in the SQL call.
* @return bool true if a matching record exists, else false.
*/
function record_exists_select($table, $select='') {
global $CFG;
if ($select) {
$select = 'WHERE '.$select;
}
return record_exists_sql('SELECT * FROM '. $CFG->prefix . $table . ' ' . $select);
}
/**
* Test whether a SQL SELECT statement returns any records.
*
* This function returns true if the SQL statement executes
* without any errors and returns at least one record.
*
* @param string $sql The SQL statement to execute.
* @return bool true if the SQL executes without errors and returns at least one record.
*/
function record_exists_sql($sql) {
$limitfrom = 0; /// Number of records to skip
$limitnum = 1; /// Number of records to retrieve
$rs = get_recordset_sql($sql, $limitfrom, $limitnum);
if ($rs && $rs->RecordCount() > 0) {
return true;
} else {
return false;
}
}
/**
* Count the records in a table where all the given fields match the given values.
*
* @uses $CFG
* @param string $table The table to query.
* @param string $field1 the first field to check (optional).
* @param string $value1 the value field1 must have (requred if field1 is given, else optional).
* @param string $field2 the second field to check (optional).
* @param string $value2 the value field2 must have (requred if field2 is given, else optional).
* @param string $field3 the third field to check (optional).
* @param string $value3 the value field3 must have (requred if field3 is given, else optional).
* @return int The count of records returned from the specified criteria.
*/
function count_records($table, $field1='', $value1='', $field2='', $value2='', $field3='', $value3='') {
global $CFG;
$select = where_clause($field1, $value1, $field2, $value2, $field3, $value3);
return count_records_sql('SELECT COUNT(*) FROM '. $CFG->prefix . $table .' '. $select);
}
/**
* Count the records in a table which match a particular WHERE clause.
*
* @uses $CFG
* @param string $table The database table to be checked against.
* @param string $select A fragment of SQL to be used in a WHERE clause in the SQL call.
* @param string $countitem The count string to be used in the SQL call. Default is COUNT(*).
* @return int The count of records returned from the specified criteria.
*/
function count_records_select($table, $select='', $countitem='COUNT(*)') {
global $CFG;
if ($select) {
$select = 'WHERE '.$select;
}
return count_records_sql('SELECT '. $countitem .' FROM '. $CFG->prefix . $table .' '. $select);
}
/**
* Get the result of a SQL SELECT COUNT(...) query.
*
* Given a query that counts rows, return that count. (In fact,
* given any query, return the first field of the first record
* returned. However, this method should only be used for the
* intended purpose.) If an error occurrs, 0 is returned.
*
* @uses $CFG
* @uses $db
* @param string $sql The SQL string you wish to be executed.
* @return int the count. If an error occurrs, 0 is returned.
*/
function count_records_sql($sql) {
$rs = get_recordset_sql($sql);
if ($rs) {
return reset($rs->fields);
} else {
return 0;
}
}
/// GENERIC FUNCTIONS TO GET, INSERT, OR UPDATE DATA ///////////////////////////////////
/**
* Get a single record as an object
*
* @uses $CFG
* @param string $table The table to select from.
* @param string $field1 the first field to check (optional).
* @param string $value1 the value field1 must have (requred if field1 is given, else optional).
* @param string $field2 the second field to check (optional).
* @param string $value2 the value field2 must have (requred if field2 is given, else optional).
* @param string $field3 the third field to check (optional).
* @param string $value3 the value field3 must have (requred if field3 is given, else optional).
* @return mixed a fieldset object containing the first mathcing record, or false if none found.
*/
function get_record($table, $field1, $value1, $field2='', $value2='', $field3='', $value3='', $fields='*') {
global $CFG, $record_cache, $record_cache_count;
// Check to see whether this record is eligible for caching (fields=*, only condition is id)
$docache = false;
if (!empty($CFG->enablerecordcache) && $field1=='id' && !$field2 && !$field3 && $fields=='*') {
$docache = true;
// If it's in the cache, return it
if (!empty($record_cache[$table][$value1])) {
return $record_cache[$table][$value1];
}
}
$select = where_clause($field1, $value1, $field2, $value2, $field3, $value3);
$record = get_record_sql('SELECT '.$fields.' FROM '. $CFG->prefix . $table .' '. $select);
// If we're caching records, store this one (supposing we got something - we don't cache failures)
if ($record && $docache && $record_cache_count<$CFG->enablerecordcache) {
$record_cache[$table][$value1] = $record;
// We only cache records up to a limit. This is to prevent memory usage becoming
// unreasonably high for pages which do things like, load every student record in
// a course, or some such.
$record_cache_count++;
}
return $record;
}
/**
* Get a single record as an object using an SQL statement
*
* The SQL statement should normally only return one record. In debug mode
* you will get a warning if more record is returned (unless you
* set $expectmultiple to true). In non-debug mode, it just returns
* the first record.
*
* @uses $CFG
* @uses $db
* @param string $sql The SQL string you wish to be executed, should normally only return one record.
* @param bool $expectmultiple If the SQL cannot be written to conviniently return just one record,
* set this to true to hide the debug message.
* @param bool $nolimit sometimes appending ' LIMIT 1' to the SQL causes an error. Set this to true
* to stop your SQL being modified. This argument should probably be deprecated.
* @return Found record as object. False if not found or error
*/
function get_record_sql($sql, $expectmultiple=false, $nolimit=false) {
global $CFG;
/// Default situation
$limitfrom = 0; /// Number of records to skip
$limitnum = 1; /// Number of records to retrieve
/// Only a few uses of the 2nd and 3rd parameter have been found
/// I think that we should avoid to use them completely, one
/// record is one record, and everything else should return error.
/// So the proposal is to change all the uses, (4-5 inside Moodle
/// Core), drop them from the definition and delete the next two
/// "if" sentences. (eloy, 2006-08-19)
if ($nolimit) {
$limitfrom = 0;
$limitnum = 0;
} else if ($expectmultiple) {
$limitfrom = 0;
$limitnum = 1;
} else if (debugging()) {
// Debugging mode - don't use a limit of 1, but do change the SQL, because sometimes that
// causes errors, and in non-debug mode you don't see the error message and it is
// impossible to know what's wrong.
$limitfrom = 0;
$limitnum = 100;
}
if (!$rs = get_recordset_sql($sql, $limitfrom, $limitnum)) {
return false;
}
$recordcount = $rs->RecordCount();
if ($recordcount == 0) { // Found no records
return false;
} else if ($recordcount == 1) { // Found one record
/// DIRTY HACK to retrieve all the ' ' (1 space) fields converted back
/// to '' (empty string) for Oracle. It's the only way to work with
/// all those NOT NULL DEFAULT '' fields until we definetively delete them
if ($CFG->dbtype == 'oci8po') {
array_walk($rs->fields, 'onespace2empty');
}
/// End od DIRTY HACK
return (object)$rs->fields;
} else { // Error: found more than one record
notify('Error: Turn off debugging to hide this error.');
notify($sql . '(with limits ' . $limitfrom . ', ' . $limitnum . ')');
if ($records = $rs->GetAssoc(true)) {
notify('Found more than one record in get_record_sql !');
print_object($records);
} else {
notify('Very strange error in get_record_sql !');
print_object($rs);
}
print_continue("$CFG->wwwroot/$CFG->admin/config.php");
}
}
/**
* Gets one record from a table, as an object
*
* @uses $CFG
* @param string $table The database table to be checked against.
* @param string $select A fragment of SQL to be used in a where clause in the SQL call.
* @param string $fields A comma separated list of fields to be returned from the chosen table.
* @return object|false Returns an array of found records (as objects) or false if no records or error occured.
*/
function get_record_select($table, $select='', $fields='*') {
global $CFG;
if ($select) {
$select = 'WHERE '. $select;
}
return get_record_sql('SELECT '. $fields .' FROM '. $CFG->prefix . $table .' '. $select);
}
/**
* Get a number of records as an ADODB RecordSet.
*
* Selects records from the table $table.
*
* If specified, only records where the field $field has value $value are retured.
*
* If specified, the results will be sorted as specified by $sort. This
* is added to the SQL as "ORDER BY $sort". Example values of $sort
* mightbe "time ASC" or "time DESC".
*
* If $fields is specified, only those fields are returned.
*
* This function is internal to datalib, and should NEVER should be called directly
* from general Moodle scripts. Use get_record, get_records etc.
*
* If you only want some of the records, specify $limitfrom and $limitnum.
* The query will skip the first $limitfrom records (according to the sort
* order) and then return the next $limitnum records. If either of $limitfrom
* or $limitnum is specified, both must be present.
*
* The return value is an ADODB RecordSet object
* @link http://phplens.com/adodb/reference.functions.adorecordset.html
* if the query succeeds. If an error occurrs, false is returned.
*
* @param string $table the table to query.
* @param string $field a field to check (optional).
* @param string $value the value the field must have (requred if field1 is given, else optional).
* @param string $sort an order to sort the results in (optional, a valid SQL ORDER BY parameter).
* @param string $fields a comma separated list of fields to return (optional, by default all fields are returned).
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an ADODB RecordSet object, or false if an error occured.
*/
function get_recordset($table, $field='', $value='', $sort='', $fields='*', $limitfrom='', $limitnum='') {
if ($field) {
$select = "$field = '$value'";
} else {
$select = '';
}
return get_recordset_select($table, $select, $sort, $fields, $limitfrom, $limitnum);
}
/**
* Get a number of records as an ADODB RecordSet.
*
* If given, $select is used as the SELECT parameter in the SQL query,
* otherwise all records from the table are returned.
*
* Other arguments and the return type as for @see function get_recordset.
*
* @uses $CFG
* @param string $table the table to query.
* @param string $select A fragment of SQL to be used in a where clause in the SQL call.
* @param string $sort an order to sort the results in (optional, a valid SQL ORDER BY parameter).
* @param string $fields a comma separated list of fields to return (optional, by default all fields are returned).
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an ADODB RecordSet object, or false if an error occured.
*/
function get_recordset_select($table, $select='', $sort='', $fields='*', $limitfrom='', $limitnum='') {
global $CFG;
if ($select) {
$select = ' WHERE '. $select;
}
if ($sort) {
$sort = ' ORDER BY '. $sort;
}
return get_recordset_sql('SELECT '. $fields .' FROM '. $CFG->prefix . $table . $select . $sort, $limitfrom, $limitnum);
}
/**
* Get a number of records as an ADODB RecordSet.
*
* Only records where $field takes one of the values $values are returned.
* $values should be a comma-separated list of values, for example "4,5,6,10"
* or "'foo','bar','baz'".
*
* Other arguments and the return type as for @see function get_recordset.
*
* @param string $table the table to query.
* @param string $field a field to check (optional).
* @param string $values comma separated list of values the field must have (requred if field is given, else optional).
* @param string $sort an order to sort the results in (optional, a valid SQL ORDER BY parameter).
* @param string $fields a comma separated list of fields to return (optional, by default all fields are returned).
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an ADODB RecordSet object, or false if an error occured.
*/
function get_recordset_list($table, $field='', $values='', $sort='', $fields='*', $limitfrom='', $limitnum='') {
if ($field) {
$select = "$field IN ($values)";
} else {
$select = '';
}
return get_recordset_select($table, $select, $sort, $fields, $limitfrom, $limitnum);
}
/**
* Get a number of records as an ADODB RecordSet. $sql must be a complete SQL query.
* This function is internal to datalib, and should NEVER should be called directly
* from general Moodle scripts. Use get_record, get_records etc.
*
* The return type is as for @see function get_recordset.
*
* @uses $CFG
* @uses $db
* @param string $sql the SQL select query to execute.
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an ADODB RecordSet object, or false if an error occured.
*/
function get_recordset_sql($sql, $limitfrom=null, $limitnum=null) {
global $CFG, $db;
if (empty($db)) {
return false;
}
/// Temporary hack as part of phasing out all access to obsolete user tables XXX
if (!empty($CFG->rolesactive)) {
if (strpos($sql, $CFG->prefix.'user_students') ||
strpos($sql, $CFG->prefix.'user_teachers') ||
strpos($sql, $CFG->prefix.'user_coursecreators') ||
strpos($sql, $CFG->prefix.'user_admins')) {
if (debugging()) { var_dump(debug_backtrace()); }
error('This SQL relies on obsolete tables! Your code must be fixed by a developer.');
}
}
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
if ($limitfrom || $limitnum) {
///Special case, 0 must be -1 for ADOdb
$limitfrom = empty($limitfrom) ? -1 : $limitfrom;
$limitnum = empty($limitnum) ? -1 : $limitnum;
$rs = $db->SelectLimit($sql, $limitnum, $limitfrom);
} else {
$rs = $db->Execute($sql);
}
if (!$rs) {
debugging($db->ErrorMsg() .'<br /><br />'. $sql);
if (!empty($CFG->dblogerror)) {
$debug=array_shift(debug_backtrace());
error_log("SQL ".$db->ErrorMsg()." in {$debug['file']} on line {$debug['line']}. STATEMENT: $sql with limits ($limitfrom, $limitnum)");
}
return false;
}
return $rs;
}
/**
* Utility function used by the following 4 methods.
*
* @param object an ADODB RecordSet object.
* @return mixed mixed an array of objects, or false if an error occured or the RecordSet was empty.
*/
function recordset_to_array($rs) {
global $CFG;
if ($rs && $rs->RecordCount() > 0) {
/// First of all, we are going to get the name of the first column
/// to introduce it back after transforming the recordset to assoc array
/// See http://docs.moodle.org/en/XMLDB_Problems, fetch mode problem.
$firstcolumn = $rs->FetchField(0);
/// Get the whole associative array
if ($records = $rs->GetAssoc(true)) {
foreach ($records as $key => $record) {
/// Really DIRTY HACK for Oracle, but it's the only way to make it work
/// until we got all those NOT NULL DEFAULT '' out from Moodle
if ($CFG->dbtype == 'oci8po') {
array_walk($record, 'onespace2empty');
}
/// End of DIRTY HACK
$record[$firstcolumn->name] = $key;/// Re-add the assoc field
$objects[$key] = (object) $record; /// To object
}
return $objects;
/// Fallback in case we only have 1 field in the recordset. MDL-5877
} else if ($rs->_numOfFields == 1 && $records = $rs->GetRows()) {
foreach ($records as $key => $record) {
/// Really DIRTY HACK for Oracle, but it's the only way to make it work
/// until we got all those NOT NULL DEFAULT '' out from Moodle
if ($CFG->dbtype == 'oci8po') {
array_walk($record, 'onespace2empty');
}
/// End of DIRTY HACK
$objects[$record[$firstcolumn->name]] = (object) $record; /// The key is the first column value (like Assoc)
}
return $objects;
} else {
return false;
}
} else {
return false;
}
}
/**
* This function is used to convert all the Oracle 1-space defaults to the empty string
* like a really DIRTY HACK to allow it to work better until all those NOT NULL DEFAULT ''
* fields will be out from Moodle.
* @param string the string to be converted to '' (empty string) if it's ' ' (one space)
* @param mixed the key of the array in case we are using this function from array_walk,
* defaults to null for other (direct) uses
* @return boolean always true (the converted variable is returned by reference)
*/
function onespace2empty(&$item, $key=null) {
$item = $item == ' ' ? '' : $item;
return true;
}
///End DIRTY HACK
/**
* Get a number of records as an array of objects.
*
* If the query succeeds and returns at least one record, the
* return value is an array of objects, one object for each
* record found. The array key is the value from the first
* column of the result set. The object associated with that key
* has a member variable for each column of the results.
*
* @param string $table the table to query.
* @param string $field a field to check (optional).
* @param string $value the value the field must have (requred if field1 is given, else optional).
* @param string $sort an order to sort the results in (optional, a valid SQL ORDER BY parameter).
* @param string $fields a comma separated list of fields to return (optional, by default all fields are returned).
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an array of objects, or false if no records were found or an error occured.
*/
function get_records($table, $field='', $value='', $sort='', $fields='*', $limitfrom='', $limitnum='') {
$rs = get_recordset($table, $field, $value, $sort, $fields, $limitfrom, $limitnum);
return recordset_to_array($rs);
}
/**
* Get a number of records as an array of objects.
*
* Return value as for @see function get_records.
*
* @param string $table the table to query.
* @param string $select A fragment of SQL to be used in a where clause in the SQL call.
* @param string $sort an order to sort the results in (optional, a valid SQL ORDER BY parameter).
* @param string $fields a comma separated list of fields to return (optional, by default all fields are returned).
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an array of objects, or false if no records were found or an error occured.
*/
function get_records_select($table, $select='', $sort='', $fields='*', $limitfrom='', $limitnum='') {
$rs = get_recordset_select($table, $select, $sort, $fields, $limitfrom, $limitnum);
return recordset_to_array($rs);
}
/**
* Get a number of records as an array of objects.
*
* Return value as for @see function get_records.
*
* @param string $table The database table to be checked against.
* @param string $field The field to search
* @param string $values Comma separated list of possible value
* @param string $sort Sort order (as valid SQL sort parameter)
* @param string $fields A comma separated list of fields to be returned from the chosen table.
* @return mixed an array of objects, or false if no records were found or an error occured.
*/
function get_records_list($table, $field='', $values='', $sort='', $fields='*', $limitfrom='', $limitnum='') {
$rs = get_recordset_list($table, $field, $values, $sort, $fields, $limitfrom, $limitnum);
return recordset_to_array($rs);
}
/**
* Get a number of records as an array of objects.
*
* Return value as for @see function get_records.
*
* @param string $sql the SQL select query to execute.
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an array of objects, or false if no records were found or an error occured.
*/
function get_records_sql($sql, $limitfrom='', $limitnum='') {
$rs = get_recordset_sql($sql, $limitfrom, $limitnum);
return recordset_to_array($rs);
}
/**
* Utility function used by the following 3 methods.
*
* @param object an ADODB RecordSet object with two columns.
* @return mixed an associative array, or false if an error occured or the RecordSet was empty.
*/
function recordset_to_menu($rs) {
global $CFG;
if ($rs && $rs->RecordCount() > 0) {
$keys = array_keys($rs->fields);
$key0=$keys[0];
$key1=$keys[1];
while (!$rs->EOF) {
$menu[$rs->fields[$key0]] = $rs->fields[$key1];
$rs->MoveNext();
}
/// Really DIRTY HACK for Oracle, but it's the only way to make it work
/// until we got all those NOT NULL DEFAULT '' out from Moodle
if ($CFG->dbtype == 'oci8po') {
array_walk($menu, 'onespace2empty');
}
/// End of DIRTY HACK
return $menu;
} else {
return false;
}
}
/**
* Get the first two columns from a number of records as an associative array.
*
* Arguments as for @see function get_recordset.
*
* If no errors occur, and at least one records is found, the return value
* is an associative whose keys come from the first field of each record,
* and whose values are the corresponding second fields. If no records are found,
* or an error occurs, false is returned.
*
* @param string $table the table to query.
* @param string $field a field to check (optional).
* @param string $value the value the field must have (requred if field1 is given, else optional).
* @param string $sort an order to sort the results in (optional, a valid SQL ORDER BY parameter).
* @param string $fields a comma separated list of fields to return (optional, by default all fields are returned).
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an associative array, or false if no records were found or an error occured.
*/
function get_records_menu($table, $field='', $value='', $sort='', $fields='*', $limitfrom='', $limitnum='') {
$rs = get_recordset($table, $field, $value, $sort, $fields, $limitfrom, $limitnum);
return recordset_to_menu($rs);
}
/**
* Get the first two columns from a number of records as an associative array.
*
* Arguments as for @see function get_recordset_select.
* Return value as for @see function get_records_menu.
*
* @param string $table The database table to be checked against.
* @param string $select A fragment of SQL to be used in a where clause in the SQL call.
* @param string $sort Sort order (optional) - a valid SQL order parameter
* @param string $fields A comma separated list of fields to be returned from the chosen table.
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an associative array, or false if no records were found or an error occured.
*/
function get_records_select_menu($table, $select='', $sort='', $fields='*', $limitfrom='', $limitnum='') {
$rs = get_recordset_select($table, $select, $sort, $fields, $limitfrom, $limitnum);
return recordset_to_menu($rs);
}
/**
* Get the first two columns from a number of records as an associative array.
*
* Arguments as for @see function get_recordset_sql.
* Return value as for @see function get_records_menu.
*
* @param string $sql The SQL string you wish to be executed.
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return mixed an associative array, or false if no records were found or an error occured.
*/
function get_records_sql_menu($sql, $limitfrom='', $limitnum='') {
$rs = get_recordset_sql($sql, $limitfrom, $limitnum);
return recordset_to_menu($rs);
}
/**
* Get a single value from a table row where all the given fields match the given values.
*
* @param string $table the table to query.
* @param string $return the field to return the value of.
* @param string $field1 the first field to check (optional).
* @param string $value1 the value field1 must have (requred if field1 is given, else optional).
* @param string $field2 the second field to check (optional).
* @param string $value2 the value field2 must have (requred if field2 is given, else optional).
* @param string $field3 the third field to check (optional).
* @param string $value3 the value field3 must have (requred if field3 is given, else optional).
* @return mixed the specified value, or false if an error occured.
*/
function get_field($table, $return, $field1, $value1, $field2='', $value2='', $field3='', $value3='') {
global $CFG;
$select = where_clause($field1, $value1, $field2, $value2, $field3, $value3);
return get_field_sql('SELECT ' . $return . ' FROM ' . $CFG->prefix . $table . ' ' . $select);
}
/**
* Get a single value from a table row where a particular select clause is true.
*
* @uses $CFG
* @param string $table the table to query.
* @param string $return the field to return the value of.
* @param string $select A fragment of SQL to be used in a where clause in the SQL call.
* @return mixed the specified value, or false if an error occured.
*/
function get_field_select($table, $return, $select) {
global $CFG;
if ($select) {
$select = 'WHERE '. $select;
}
return get_field_sql('SELECT ' . $return . ' FROM ' . $CFG->prefix . $table . ' ' . $select);
}
/**
* Get a single value from a table.
*
* @param string $sql an SQL statement expected to return a single value.
* @return mixed the specified value, or false if an error occured.
*/
function get_field_sql($sql) {
global $CFG;
/// Strip potential LIMIT uses arriving here, debugging them (MDL-7173)
$newsql = preg_replace('/ LIMIT [0-9, ]+$/is', '', $sql);
if ($newsql != $sql) {
debugging('Incorrect use of LIMIT clause (not cross-db) in call to get_field_sql(): ' . $sql, DEBUG_DEVELOPER);
$sql = $newsql;
}
$rs = get_recordset_sql($sql, 0, 1);
if ($rs && $rs->RecordCount() == 1) {
/// DIRTY HACK to retrieve all the ' ' (1 space) fields converted back
/// to '' (empty string) for Oracle. It's the only way to work with
/// all those NOT NULL DEFAULT '' fields until we definetively delete them
if ($CFG->dbtype == 'oci8po') {
$value = reset($rs->fields);
onespace2empty($value);
return $value;
}
/// End of DIRTY HACK
return reset($rs->fields);
} else {
return false;
}
}
/**
* Get an array of data from one or more fields from a database
* use to get a column, or a series of distinct values
*
* @uses $CFG
* @uses $db
* @param string $sql The SQL string you wish to be executed.
* @return mixed|false Returns the value return from the SQL statment or false if an error occured.
* @todo Finish documenting this function
*/
function get_fieldset_sql($sql) {
global $db, $CFG;
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
$rs = $db->Execute($sql);
if (!$rs) {
debugging($db->ErrorMsg() .'<br /><br />'. $sql);
if (!empty($CFG->dblogerror)) {
$debug=array_shift(debug_backtrace());
error_log("SQL ".$db->ErrorMsg()." in {$debug['file']} on line {$debug['line']}. STATEMENT: $sql");
}
return false;
}
if ( $rs->RecordCount() > 0 ) {
$keys = array_keys($rs->fields);
$key0 = $keys[0];
$results = array();
while (!$rs->EOF) {
array_push($results, $rs->fields[$key0]);
$rs->MoveNext();
}
/// DIRTY HACK to retrieve all the ' ' (1 space) fields converted back
/// to '' (empty string) for Oracle. It's the only way to work with
/// all those NOT NULL DEFAULT '' fields until we definetively delete them
if ($CFG->dbtype == 'oci8po') {
array_walk($results, 'onespace2empty');
}
/// End of DIRTY HACK
return $results;
} else {
return false;
}
}
/**
* Set a single field in every table row where all the given fields match the given values.
*
* @uses $CFG
* @uses $db
* @param string $table The database table to be checked against.
* @param string $newfield the field to set.
* @param string $newvalue the value to set the field to.
* @param string $field1 the first field to check (optional).
* @param string $value1 the value field1 must have (requred if field1 is given, else optional).
* @param string $field2 the second field to check (optional).
* @param string $value2 the value field2 must have (requred if field2 is given, else optional).
* @param string $field3 the third field to check (optional).
* @param string $value3 the value field3 must have (requred if field3 is given, else optional).
* @return mixed An ADODB RecordSet object with the results from the SQL call or false.
*/
function set_field($table, $newfield, $newvalue, $field1, $value1, $field2='', $value2='', $field3='', $value3='') {
global $db, $CFG, $record_cache;
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
// Clear record_cache based on the parameters passed (individual record or whole table)
if (!empty($CFG->enablerecordcache)) {
if ($field1 == 'id') {
if (isset($record_cache[$table][$value1])) {
unset($record_cache[$table][$value1]);
}
} else if ($field2 == 'id') {
if (isset($record_cache[$table][$value2])) {
unset($record_cache[$table][$value2]);
}
} else if ($field3 == 'id') {
if (isset($record_cache[$table][$value3])) {
unset($record_cache[$table][$value3]);
}
} else {
if (isset($record_cache[$table])) {
unset($record_cache[$table]);
}
}
}
$select = where_clause($field1, $value1, $field2, $value2, $field3, $value3);
$dataobject = new StdClass;
$dataobject->{$newfield} = $newvalue;
// Oracle DIRTY HACK -
if ($CFG->dbtype == 'oci8po') {
oracle_dirty_hack($table, $dataobject); // Convert object to the correct "empty" values for Oracle DB
$newvalue = $dataobject->{$newfield};
}
// End DIRTY HACK
/// Under Oracle and MSSQL we have our own set field process
/// If the field being updated is clob/blob, we use our alternate update here
/// They will be updated later
if (($CFG->dbtype == 'oci8po' || $CFG->dbtype == 'mssql' || $CFG->dbtype == 'odbc_mssql' || $CFG->dbtype == 'mssql_n')
&& !empty($select)) {
/// Detect lobs
$foundclobs = array();
$foundblobs = array();
db_detect_lobs($table, $dataobject, $foundclobs, $foundblobs);
}
/// Under Oracle and MSSQL, finally, Update all the Clobs and Blobs present in the record
/// if we know we have some of them in the query
if (($CFG->dbtype == 'oci8po' || $CFG->dbtype == 'mssql' || $CFG->dbtype == 'odbc_mssql' || $CFG->dbtype == 'mssql_n')
&& !empty($select) &&
(!empty($foundclobs) || !empty($foundblobs))) {
if (!db_update_lobs($table, $select, $foundclobs, $foundblobs)) {
return false; //Some error happened while updating LOBs
} else {
return true; //Everrything was ok
}
}
/// Arriving here, standard update
return $db->Execute('UPDATE '. $CFG->prefix . $table .' SET '. $newfield .' = \''. $newvalue .'\' '. $select);
}
/**
* Delete the records from a table where all the given fields match the given values.
*
* @uses $CFG
* @uses $db
* @param string $table the table to delete from.
* @param string $field1 the first field to check (optional).
* @param string $value1 the value field1 must have (requred if field1 is given, else optional).
* @param string $field2 the second field to check (optional).
* @param string $value2 the value field2 must have (requred if field2 is given, else optional).
* @param string $field3 the third field to check (optional).
* @param string $value3 the value field3 must have (requred if field3 is given, else optional).
* @return mixed An ADODB RecordSet object with the results from the SQL call or false.
*/
function delete_records($table, $field1='', $value1='', $field2='', $value2='', $field3='', $value3='') {
global $db, $CFG, $record_cache;
// Clear record_cache based on the parameters passed (individual record or whole table)
if (!empty($CFG->enablerecordcache)) {
if ($field1 == 'id') {
if (isset($record_cache[$table][$value1])) {
unset($record_cache[$table][$value1]);
}
} else if ($field2 == 'id') {
if (isset($record_cache[$table][$value2])) {
unset($record_cache[$table][$value2]);
}
} else if ($field3 == 'id') {
if (isset($record_cache[$table][$value3])) {
unset($record_cache[$table][$value3]);
}
} else {
if (isset($record_cache[$table])) {
unset($record_cache[$table]);
}
}
}
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
$select = where_clause($field1, $value1, $field2, $value2, $field3, $value3);
return $db->Execute('DELETE FROM '. $CFG->prefix . $table .' '. $select);
}
/**
* Delete one or more records from a table
*
* @uses $CFG
* @uses $db
* @param string $table The database table to be checked against.
* @param string $select A fragment of SQL to be used in a where clause in the SQL call (used to define the selection criteria).
* @return object A PHP standard object with the results from the SQL call.
* @todo Verify return type.
*/
function delete_records_select($table, $select='') {
global $CFG, $db, $record_cache;
// Clear record_cache (whole table)
if (!empty($CFG->enablerecordcache) && isset($record_cache[$table])) {
unset($record_cache[$table]);
}
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
if ($select) {
$select = 'WHERE '.$select;
}
return $db->Execute('DELETE FROM '. $CFG->prefix . $table .' '. $select);
}
/**
* Insert a record into a table and return the "id" field if required
*
* If the return ID isn't required, then this just reports success as true/false.
* $dataobject is an object containing needed data
*
* @uses $db
* @uses $CFG
* @param string $table The database table to be checked against.
* @param array $dataobject A data object with values for one or more fields in the record
* @param bool $returnid Should the id of the newly created record entry be returned? If this option is not requested then true/false is returned.
* @param string $primarykey The primary key of the table we are inserting into (almost always "id")
*/
function insert_record($table, $dataobject, $returnid=true, $primarykey='id') {
global $db, $CFG, $empty_rs_cache;
if (empty($db)) {
return false;
}
/// Temporary hack as part of phasing out all access to obsolete user tables XXX
if (!empty($CFG->rolesactive)) {
if (in_array($table, array('user_students', 'user_teachers', 'user_coursecreators', 'user_admins'))) {
if (debugging()) { var_dump(debug_backtrace()); }
error('This SQL relies on obsolete tables ('.$table.')! Your code must be fixed by a developer.');
}
}
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
/// In Moodle we always use auto-numbering fields for the primary key
/// so let's unset it now before it causes any trouble later
unset($dataobject->{$primarykey});
/// Get an empty recordset. Cache for multiple inserts.
if (empty($empty_rs_cache[$table])) {
/// Execute a dummy query to get an empty recordset
if (!$empty_rs_cache[$table] = $db->Execute('SELECT * FROM '. $CFG->prefix . $table .' WHERE '. $primarykey .' = \'-1\'')) {
return false;
}
}
$rs = $empty_rs_cache[$table];
/// Postgres doesn't have the concept of primary key built in
/// and will return the OID which isn't what we want.
/// The efficient and transaction-safe strategy is to
/// move the sequence forward first, and make the insert
/// with an explicit id.
if ( $CFG->dbtype === 'postgres7' && $returnid == true ) {
if ($nextval = (int)get_field_sql("SELECT NEXTVAL('{$CFG->prefix}{$table}_{$primarykey}_seq')")) {
$dataobject->{$primarykey} = $nextval;
}
}
/// Begin DIRTY HACK
if ($CFG->dbtype == 'oci8po') {
oracle_dirty_hack($table, $dataobject); // Convert object to the correct "empty" values for Oracle DB
}
/// End DIRTY HACK
/// Under Oracle and MSSQL we have our own insert record process
/// detect all the clob/blob fields and change their contents to @#CLOB#@ and @#BLOB#@
/// saving them into $foundclobs and $foundblobs [$fieldname]->contents
/// Same for mssql (only processing blobs - image fields)
if (($CFG->dbtype == 'oci8po' || $CFG->dbtype == 'mssql' || $CFG->dbtype == 'odbc_mssql' || $CFG->dbtype == 'mssql_n')) {
$foundclobs = array();
$foundblobs = array();
db_detect_lobs($table, $dataobject, $foundclobs, $foundblobs);
}
/// Under Oracle, if the primary key inserted has been requested OR
/// if there are LOBs to insert, we calculate the next value via
/// explicit query to the sequence.
/// Else, the pre-insert trigger will do the job, because the primary
/// key isn't needed at all by the rest of PHP code
if ( $CFG->dbtype === 'oci8po' && ($returnid == true || !empty($foundclobs) || !empty($foundblobs))) {
/// We need this here (move this function to dmlib?)
include_once($CFG->libdir . '/ddllib.php');
$xmldb_table = new XMLDBTable($table);
$seqname = find_sequence_name($xmldb_table);
if (!$seqname) {
/// Fallback, seqname not found, something is wrong. Inform and use the alternative getNameForObject() method
debugging('Sequence name for table ' . $table->getName() . ' not found', DEBUG_DEVELOPER);
$generator = new XMLDBoci8po();
$generator->setPrefix($CFG->prefix);
$seqname = $generator->getNameForObject($table, $primarykey, 'seq');
}
if ($nextval = (int)$db->GenID($seqname)) {
$dataobject->{$primarykey} = $nextval;
}
}
/// Get the correct SQL from adoDB
if (!$insertSQL = $db->GetInsertSQL($rs, (array)$dataobject, true)) {
return false;
}
/// Under Oracle and MSSQL, replace all the '@#CLOB#@' and '@#BLOB#@' ocurrences to proper default values
/// if we know we have some of them in the query
if (($CFG->dbtype == 'oci8po' || $CFG->dbtype == 'mssql' || $CFG->dbtype == 'odbc_mssql' || $CFG->dbtype == 'mssql_n') &&
(!empty($foundclobs) || !empty($foundblobs))) {
/// Initial configuration, based on DB
switch ($CFG->dbtype) {
case 'oci8po':
$clobdefault = 'empty_clob()'; //Value of empty default clobs for this DB
$blobdefault = 'empty_blob()'; //Value of empty default blobs for this DB
break;
case 'mssql':
case 'odbc_mssql':
case 'mssql_n':
$clobdefault = 'null'; //Value of empty default clobs for this DB (under mssql this won't be executed
$blobdefault = 'null'; //Value of empty default blobs for this DB
break;
}
$insertSQL = str_replace("'@#CLOB#@'", $clobdefault, $insertSQL);
$insertSQL = str_replace("'@#BLOB#@'", $blobdefault, $insertSQL);
}
/// Run the SQL statement
if (!$rs = $db->Execute($insertSQL)) {
debugging($db->ErrorMsg() .'<br /><br />'.$insertSQL);
if (!empty($CFG->dblogerror)) {
$debug=array_shift(debug_backtrace());
error_log("SQL ".$db->ErrorMsg()." in {$debug['file']} on line {$debug['line']}. STATEMENT: $insertSQL");
}
return false;
}
/// Under Oracle, finally, Update all the Clobs and Blobs present in the record
/// if we know we have some of them in the query
if ($CFG->dbtype == 'oci8po' &&
!empty($dataobject->{$primarykey}) &&
(!empty($foundclobs) || !empty($foundblobs))) {
if (!db_update_lobs($table, $dataobject->{$primarykey}, $foundclobs, $foundblobs)) {
return false; //Some error happened while updating LOBs
}
}
/// If a return ID is not needed then just return true now (but not in MSSQL DBs, where we may have some pending tasks)
if (!$returnid && !($CFG->dbtype == 'mssql' || $CFG->dbtype == 'odbc_mssql' || $CFG->dbtype == 'mssql_n')) {
return true;
}
/// We already know the record PK if it's been passed explicitly,
/// or if we've retrieved it from a sequence (Postgres and Oracle).
if (!empty($dataobject->{$primarykey})) {
return $dataobject->{$primarykey};
}
/// This only gets triggered with MySQL and MSQL databases
/// however we have some postgres fallback in case we failed
/// to find the sequence.
$id = $db->Insert_ID();
/// Under MSSQL all the Blobs (IMAGE) present in the record
/// if we know we have some of them in the query
if (($CFG->dbtype == 'mssql' || $CFG->dbtype == 'odbc_mssql' || $CFG->dbtype == 'mssql_n') &&
!empty($id) &&
(!empty($foundclobs) || !empty($foundblobs))) {
if (!db_update_lobs($table, $id, $foundclobs, $foundblobs)) {
return false; //Some error happened while updating LOBs
}
}
if ($CFG->dbtype === 'postgres7') {
// try to get the primary key based on id
if ( ($rs = $db->Execute('SELECT '. $primarykey .' FROM '. $CFG->prefix . $table .' WHERE oid = '. $id))
&& ($rs->RecordCount() == 1) ) {
trigger_error("Retrieved $primarykey from oid on table $table because we could not find the sequence.");
return (integer)reset($rs->fields);
}
trigger_error('Failed to retrieve primary key after insert: SELECT '. $primarykey .
' FROM '. $CFG->prefix . $table .' WHERE oid = '. $id);
return false;
}
return (integer)$id;
}
/**
* Update a record in a table
*
* $dataobject is an object containing needed data
* Relies on $dataobject having a variable "id" to
* specify the record to update
*
* @uses $CFG
* @uses $db
* @param string $table The database table to be checked against.
* @param array $dataobject An object with contents equal to fieldname=>fieldvalue. Must have an entry for 'id' to map to the table specified.
* @return bool
*/
function update_record($table, $dataobject) {
global $db, $CFG, $record_cache;
if (! isset($dataobject->id) ) {
return false;
}
// Remove this record from record cache since it will change
if (!empty($CFG->enablerecordcache) && isset($record_cache[$table][$dataobject->id])) {
unset($record_cache[$table][$dataobject->id]);
}
/// Temporary hack as part of phasing out all access to obsolete user tables XXX
if (!empty($CFG->rolesactive)) {
if (in_array($table, array('user_students', 'user_teachers', 'user_coursecreators', 'user_admins'))) {
if (debugging()) { var_dump(debug_backtrace()); }
error('This SQL relies on obsolete tables ('.$table.')! Your code must be fixed by a developer.');
}
}
/// Begin DIRTY HACK
if ($CFG->dbtype == 'oci8po') {
oracle_dirty_hack($table, $dataobject); // Convert object to the correct "empty" values for Oracle DB
}
/// End DIRTY HACK
/// Under Oracle and MSSQL we have our own update record process
/// detect all the clob/blob fields and delete them from the record being updated
/// saving them into $foundclobs and $foundblobs [$fieldname]->contents
/// They will be updated later
if (($CFG->dbtype == 'oci8po' || $CFG->dbtype == 'mssql' || $CFG->dbtype == 'odbc_mssql' || $CFG->dbtype == 'mssql_n')
&& !empty($dataobject->id)) {
/// Detect lobs
$foundclobs = array();
$foundblobs = array();
db_detect_lobs($table, $dataobject, $foundclobs, $foundblobs, true);
}
// Determine all the fields in the table
if (!$columns = $db->MetaColumns($CFG->prefix . $table)) {
return false;
}
$data = (array)$dataobject;
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
// Pull out data matching these fields
$ddd = array();
foreach ($columns as $column) {
if ($column->name <> 'id' and isset($data[$column->name]) ) {
$ddd[$column->name] = $data[$column->name];
// PostgreSQL bytea support
if ($CFG->dbtype == 'postgres7' && $column->type == 'bytea') {
$ddd[$column->name] = $db->BlobEncode($ddd[$column->name]);
}
}
}
// Construct SQL queries
$numddd = count($ddd);
$count = 0;
$update = '';
/// Only if we have fields to be updated (this will prevent both wrong updates +
/// updates of only LOBs in Oracle
if ($numddd) {
foreach ($ddd as $key => $value) {
$count++;
$update .= $key .' = \''. $value .'\''; // All incoming data is already quoted
if ($count < $numddd) {
$update .= ', ';
}
}
if (!$rs = $db->Execute('UPDATE '. $CFG->prefix . $table .' SET '. $update .' WHERE id = \''. $dataobject->id .'\'')) {
debugging($db->ErrorMsg() .'<br /><br />UPDATE '. $CFG->prefix . $table .' SET '. $update .' WHERE id = \''. $dataobject->id .'\'');
if (!empty($CFG->dblogerror)) {
$debug=array_shift(debug_backtrace());
error_log("SQL ".$db->ErrorMsg()." in {$debug['file']} on line {$debug['line']}. STATEMENT: UPDATE $CFG->prefix$table SET $update WHERE id = '$dataobject->id'");
}
return false;
}
}
/// Under Oracle AND MSSQL, finally, Update all the Clobs and Blobs present in the record
/// if we know we have some of them in the query
if (($CFG->dbtype == 'oci8po' || $CFG->dbtype == 'mssql' || $CFG->dbtype == 'odbc_mssql' || $CFG->dbtype == 'mssql_n')
&& !empty($dataobject->id) &&
(!empty($foundclobs) || !empty($foundblobs))) {
if (!db_update_lobs($table, $dataobject->id, $foundclobs, $foundblobs)) {
return false; //Some error happened while updating LOBs
}
}
return true;
}
/**
* Returns the proper SQL to do paging
*
* @uses $CFG
* @param string $page Offset page number
* @param string $recordsperpage Number of records per page
* @deprecated Moodle 1.7 use the new $limitfrom, $limitnum available in all
* the get_recordXXX() funcions.
* @return string
*/
function sql_paging_limit($page, $recordsperpage) {
global $CFG;
debugging('Function sql_paging_limit() is deprecated. Replace it with the correct use of limitfrom, limitnum parameters', DEBUG_DEVELOPER);
switch ($CFG->dbtype) {
case 'postgres7':
return 'LIMIT '. $recordsperpage .' OFFSET '. $page;
default:
return 'LIMIT '. $page .','. $recordsperpage;
}
}
/**
* Returns the proper SQL to do LIKE in a case-insensitive way
*
* Note the LIKE are case sensitive for Oracle. Oracle 10g is required to use
* the caseinsensitive search using regexp_like() or NLS_COMP=LINGUISTIC :-(
* See http://docs.moodle.org/en/XMLDB_Problems#Case-insensitive_searches
*
* @uses $CFG
* @return string
*/
function sql_ilike() {
global $CFG;
switch ($CFG->dbtype) {
case 'postgres7':
return 'ILIKE';
default:
return 'LIKE';
}
}
/**
* Returns the proper SQL (for the dbms in use) to concatenate $firstname and $lastname
*
* @uses $CFG
* @param string $firstname User's first name
* @param string $lastname User's last name
* @return string
*/
function sql_fullname($firstname='firstname', $lastname='lastname') {
return sql_concat($firstname, "' '", $lastname);
}
/**
* Returns the proper SQL to do CONCAT between the elements passed
* Can take many parameters - just a passthrough to $db->Concat()
*
* @uses $db
* @param string $element
* @return string
*/
function sql_concat() {
global $db;
$args = func_get_args();
return call_user_func_array(array($db, 'Concat'), $args);
}
/**
* Returns the proper SQL to do CONCAT between the elements passed
* with a given separator
*
* @uses $db
* @param string $separator
* @param array $elements
* @return string
*/
function sql_concat_join($separator="' '", $elements=array()) {
global $db;
// copy to ensure pass by value
$elem = $elements;
// Intersperse $elements in the array.
// Add items to the array on the fly, walking it
// _backwards_ splicing the elements in. The loop definition
// should skip first and last positions.
for ($n=count($elem)-1; $n > 0 ; $n--) {
array_splice($elem, $n, 0, $separator);
}
return call_user_func_array(array($db, 'Concat'), $elem);
}
/**
* Returns the proper SQL to do IS NULL
* @uses $CFG
* @param string $fieldname The field to add IS NULL to
* @return string
*/
function sql_isnull($fieldname) {
global $CFG;
switch ($CFG->dbtype) {
case 'mysql':
return $fieldname.' IS NULL';
default:
return $fieldname.' IS NULL';
}
}
/**
* Returns the proper AS keyword to be used to aliase columns
* SQL defines the keyword as optional and nobody but PG
* seems to require it. This function should be used inside all
* the statements using column aliases.
* Note than the use of table aliases doesn't require the
* AS keyword at all, only columns for postgres.
* @uses $CFG
* @ return string the keyword
* @deprecated Moodle 1.7 because coding guidelines now enforce to use AS in column aliases
*/
function sql_as() {
global $CFG, $db;
switch ($CFG->dbtype) {
case 'postgres7':
return 'AS';
default:
return '';
}
}
/**
* Returns the proper substr() function for each DB
* Relies on ADOdb $db->substr property
*/
function sql_substr() {
global $db;
return $db->substr;
}
/**
* Returns the SQL text to be used to order by one TEXT (clob) column, because
* some RDBMS doesn't support direct ordering of such fields.
* Note that the use or queries being ordered by TEXT columns must be minimised,
* because it's really slooooooow.
* @param string fieldname the name of the TEXT field we need to order by
* @param string number of chars to use for the ordering (defaults to 32)
* @return string the piece of SQL code to be used in your statement.
*/
function sql_order_by_text($fieldname, $numchars=32) {
global $CFG;
switch ($CFG->dbtype) {
case 'mssql':
case 'mssql_n':
case 'odbc_mssql':
return 'CONVERT(varchar, ' . $fieldname . ', ' . $numchars . ')';
break;
case 'oci8po':
return 'dbms_lob.substr(' . $fieldname . ', ' . $numchars . ',1)';
break;
default:
return $fieldname;
}
}
/**
* Returns SQL to be used as a subselect to find the primary role of users.
* Geoff Cant <geoff@catalyst.net.nz> (the author) is very keen for this to
* be implemented as a view in future versions.
*
* eg if this function returns a string called $primaryroles, then you could:
* $sql = 'SELECT COUNT(DISTINCT prs.userid) FROM ('.$primary_roles.') prs
* WHERE prs.primary_roleid='.$role->id.' AND prs.courseid='.$course->id.
* ' AND prs.contextlevel = '.CONTEXT_COURSE;
*
* @return string the piece of SQL code to be used in your FROM( ) statement.
*/
function sql_primary_role_subselect() {
global $CFG;
return 'SELECT ra.userid,
ra.roleid AS primary_roleid,
ra.contextid,
r.sortorder,
r.name,
r.description,
r.shortname,
c.instanceid AS courseid,
c.contextlevel
FROM '.$CFG->prefix.'role_assignments ra
INNER JOIN '.$CFG->prefix.'role r ON ra.roleid = r.id
INNER JOIN '.$CFG->prefix.'context c ON ra.contextid = c.id
WHERE NOT EXISTS (
SELECT 1
FROM '.$CFG->prefix.'role_assignments i_ra
INNER JOIN '.$CFG->prefix.'role i_r ON i_ra.roleid = i_r.id
WHERE ra.userid = i_ra.userid AND
ra.contextid = i_ra.contextid AND
i_r.sortorder < r.sortorder
) ';
}
/**
* Prepare a SQL WHERE clause to select records where the given fields match the given values.
*
* Prepares a where clause of the form
* WHERE field1 = value1 AND field2 = value2 AND field3 = value3
* except that you need only specify as many arguments (zero to three) as you need.
*
* @param string $field1 the first field to check (optional).
* @param string $value1 the value field1 must have (requred if field1 is given, else optional).
* @param string $field2 the second field to check (optional).
* @param string $value2 the value field2 must have (requred if field2 is given, else optional).
* @param string $field3 the third field to check (optional).
* @param string $value3 the value field3 must have (requred if field3 is given, else optional).
*/
function where_clause($field1='', $value1='', $field2='', $value2='', $field3='', $value3='') {
if ($field1) {
$select = "WHERE $field1 = '$value1'";
if ($field2) {
$select .= " AND $field2 = '$value2'";
if ($field3) {
$select .= " AND $field3 = '$value3'";
}
}
} else {
$select = '';
}
return $select;
}
/**
* Get the data type of a table column, using an ADOdb MetaType() call.
*
* @uses $CFG
* @uses $db
* @param string $table The name of the database table
* @param string $column The name of the field in the table
* @return string Field type or false if error
*/
function column_type($table, $column) {
global $CFG, $db;
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; };
if(!$rs = $db->Execute('SELECT '.$column.' FROM '.$CFG->prefix.$table.' WHERE 1=2')) {
return false;
}
$field = $rs->FetchField(0);
return $rs->MetaType($field->type);
}
/**
* This function will execute an array of SQL commands, returning
* true/false if any error is found and stopping/continue as desired.
* It's widely used by all the ddllib.php functions
*
* @param array sqlarr array of sql statements to execute
* @param boolean continue to specify if must continue on error (true) or stop (false)
* @param boolean feedback to specify to show status info (true) or not (false)
* @param boolean true if everything was ok, false if some error was found
*/
function execute_sql_arr($sqlarr, $continue=true, $feedback=true) {
if (!is_array($sqlarr)) {
return false;
}
$status = true;
foreach($sqlarr as $sql) {
if (!execute_sql($sql, $feedback)) {
$status = false;
if (!$continue) {
break;
}
}
}
return $status;
}
/**
* This function, called from setup.php includes all the configuration
* needed to properly work agains any DB. It setups connection encoding
* and some other variables.
*/
function configure_dbconnection() {
global $CFG, $db;
switch ($CFG->dbtype) {
case 'mysql':
/// Set names if needed
if ($CFG->unicodedb) {
$db->Execute("SET NAMES 'utf8'");
}
break;
case 'postgres7':
/// Set names if needed
if ($CFG->unicodedb) {
$db->Execute("SET NAMES 'utf8'");
}
break;
case 'mssql':
case 'mssql_n':
case 'odbc_mssql':
/// No need to set charset. It must be specified in the driver conf
/// Allow quoted identifiers
$db->Execute('SET QUOTED_IDENTIFIER ON');
/// Force ANSI nulls so the NULL check was done by IS NULL and NOT IS NULL
/// instead of equal(=) and distinct(<>) simbols
$db->Execute('SET ANSI_NULLS ON');
/// Enable sybase quotes, so addslashes and stripslashes will use "'"
ini_set('magic_quotes_sybase', '1');
/// NOTE: Not 100% useful because GPC has been addslashed with the setting off
/// so IT'S MANDATORY TO CHANGE THIS UNDER php.ini or .htaccess for this DB
/// or to turn off magic_quotes to allow Moodle to do it properly
break;
case 'oci8po':
/// No need to set charset. It must be specified by the NLS_LANG env. variable
/// Enable sybase quotes, so addslashes and stripslashes will use "'"
ini_set('magic_quotes_sybase', '1');
/// NOTE: Not 100% useful because GPC has been addslashed with the setting off
/// so IT'S MANDATORY TO ENABLE THIS UNDER php.ini or .htaccess for this DB
/// or to turn off magic_quotes to allow Moodle to do it properly
break;
}
}
/**
* This function will handle all the records before being inserted/updated to DB for Oracle
* installations. This is because the "special feature" of Oracle where the empty string is
* equal to NULL and this presents a problem with all our currently NOT NULL default '' fields.
*
* Once Moodle DB will be free of this sort of false NOT NULLS, this hack could be removed safely
*
* Note that this function is 100% private and should be used, exclusively by DML functions
* in this file. Also, this is considered a DIRTY HACK to be removed when possible. (stronk7)
*
* This function is private and must not be used outside dmllib at all
*
* @param $table string the table where the record is going to be inserted/updated (without prefix)
* @param $dataobject object the object to be inserted/updated
* @param $usecache boolean flag to determinate if we must use the per request cache of metadata
* true to use it, false to ignore and delete it
*/
function oracle_dirty_hack ($table, &$dataobject, $usecache = true) {
global $CFG, $db, $metadata_cache;
/// Init and delete metadata cache
if (!isset($metadata_cache) || !$usecache) {
$metadata_cache = array();
}
/// For Oracle DB, empty strings are converted to NULLs in DB
/// and this breaks a lot of NOT NULL columns currenty Moodle. In the future it's
/// planned to move some of them to NULL, if they must accept empty values and this
/// piece of code will become less and less used. But, for now, we need it.
/// What we are going to do is to examine all the data being inserted and if it's
/// an empty string (NULL for Oracle) and the field is defined as NOT NULL, we'll modify
/// such data in the best form possible ("0" for booleans and numbers and " " for the
/// rest of strings. It isn't optimal, but the only way to do so.
/// In the oppsite, when retrieving records from Oracle, we'll decode " " back to
/// empty strings to allow everything to work properly. DIRTY HACK.
/// If the db isn't Oracle, return without modif
if ( $CFG->dbtype != 'oci8po') {
return;
}
/// Get Meta info to know what to change, using the cached meta if exists
if (!isset($metadata_cache[$table])) {
$metadata_cache[$table] = array_change_key_case($db->MetaColumns($CFG->prefix . $table), CASE_LOWER);
}
$columns = $metadata_cache[$table];
/// Iterate over all the fields in the insert, transforming values
/// in the best possible form
foreach ($dataobject as $fieldname => $fieldvalue) {
/// If the field doesn't exist in metadata, skip
if (!isset($columns[strtolower($fieldname)])) {
continue;
}
/// If the field ins't VARCHAR or CLOB, skip
if ($columns[strtolower($fieldname)]->type != 'VARCHAR2' && $columns[strtolower($fieldname)]->type != 'CLOB') {
continue;
}
/// If the field isn't NOT NULL, skip (it's nullable, so accept empty values)
if (!$columns[strtolower($fieldname)]->not_null) {
continue;
}
/// If the value isn't empty, skip
if (!empty($fieldvalue)) {
continue;
}
/// Now, we have one empty value, going to be inserted to one NOT NULL, VARCHAR2 or CLOB field
/// Try to get the best value to be inserted
if (gettype($fieldvalue) == 'boolean') {
$dataobject->$fieldname = '0'; /// Transform false to '0' that evaluates the same for PHP
} else if (gettype($fieldvalue) == 'integer') {
$dataobject->$fieldname = '0'; /// Transform 0 to '0' that evaluates the same for PHP
} else if (gettype($fieldvalue) == 'NULL') {
$dataobject->$fieldname = '0'; /// Transform NULL to '0' that evaluates the same for PHP
} else {
$dataobject->$fieldname = ' '; /// Transform '' to ' ' that DONT'T EVALUATE THE SAME
/// (we'll transform back again on get_records_XXX functions and others)!!
}
}
}
/// End of DIRTY HACK
/**
* This function will search for all the CLOBs and BLOBs fields passed in the dataobject, replacing
* their contents by the fixed strings '@#CLOB#@' and '@#BLOB#@' and returning one array for all the
* found CLOBS and another for all the found BLOBS
* Used by Oracle drivers to perform the two-step insertion/update of LOBs and
* by MSSQL to perform the same exclusively for BLOBs (IMAGE fields)
*
* This function is private and must not be used outside dmllib at all
*
* @param $table string the table where the record is going to be inserted/updated (without prefix)
* @param $dataobject object the object to be inserted/updated
* @param $clobs array of clobs detected
* @param $dataobject array of blobs detected
* @param $unset boolean to specify if we must unset found LOBs from the original object (true) or
* just return them modified to @#CLOB#@ and @#BLOB#@ (false)
* @param $usecache boolean flag to determinate if we must use the per request cache of metadata
* true to use it, false to ignore and delete it
*/
function db_detect_lobs ($table, &$dataobject, &$clobs, &$blobs, $unset = false, $usecache = true) {
global $CFG, $db, $metadata_cache;
$dataarray = (array)$dataobject; //Convert to array. It's supposed that PHP 4.3 doesn't iterate over objects
/// Initial configuration, based on DB
switch ($CFG->dbtype) {
case 'oci8po':
$clobdbtype = 'CLOB'; //Name of clobs for this DB
$blobdbtype = 'BLOB'; //Name of blobs for this DB
break;
case 'mssql':
case 'odbc_mssql':
case 'mssql_n':
$clobdbtype = 'NOTPROCESSES'; //Name of clobs for this DB (under mssql flavours we don't process CLOBS)
$blobdbtype = 'IMAGE'; //Name of blobs for this DB
break;
default:
return; //Other DB doesn't need this two step to happen, prevent continue
}
/// Init and delete metadata cache
if (!isset($metadata_cache) || !$usecache) {
$metadata_cache = array();
}
/// Get Meta info to know what to change, using the cached meta if exists
if (!isset($metadata_cache[$table])) {
$metadata_cache[$table] = array_change_key_case($db->MetaColumns($CFG->prefix . $table), CASE_LOWER);
}
$columns = $metadata_cache[$table];
foreach ($dataarray as $fieldname => $fieldvalue) {
/// If the field doesn't exist in metadata, skip
if (!isset($columns[strtolower($fieldname)])) {
continue;
}
/// If the field is CLOB, update its value to '@#CLOB#@' and store it in the $clobs array
if (strtoupper($columns[strtolower($fieldname)]->type) == $clobdbtype) {
/// Oracle optimization. CLOBs under 4000cc can be directly inserted (no need to apply 2-phases to them)
if ($db->dbtype = 'oci8po' && strlen($dataobject->$fieldname) < 4000) {
continue;
}
$clobs[$fieldname] = $dataobject->$fieldname;
if ($unset) {
unset($dataobject->$fieldname);
} else {
$dataobject->$fieldname = '@#CLOB#@';
}
continue;
}
/// If the field is BLOB OR IMAGE, update its value to '@#BLOB#@' and store it in the $blobs array
if (strtoupper($columns[strtolower($fieldname)]->type) == $blobdbtype) {
$blobs[$fieldname] = $dataobject->$fieldname;
if ($unset) {
unset($dataobject->$fieldname);
} else {
$dataobject->$fieldname = '@#BLOB#@';
}
continue;
}
}
}
/**
* This function will iterate over $clobs and $blobs array, executing the needed
* UpdateClob() and UpdateBlob() ADOdb function calls to store LOBs contents properly
* Records to be updated are always searched by PK (id always!)
*
* Used by Orace CLOBS and BLOBS and MSSQL IMAGES
*
* This function is private and must not be used outside dmllib at all
*
* @param $table string the table where the record is going to be inserted/updated (without prefix)
* @param $sqlcondition mixed value defining the records to be LOB-updated. It it's a number, must point
* to the PK og the table (id field), else it's processed as one harcoded SQL condition (WHERE clause)
* @param $clobs array of clobs to be updated
* @param $blobs array of blobs to be updated
*/
function db_update_lobs ($table, $sqlcondition, &$clobs, &$blobs) {
global $CFG, $db;
$status = true;
/// Initial configuration, based on DB
switch ($CFG->dbtype) {
case 'oci8po':
$clobdbtype = 'CLOB'; //Name of clobs for this DB
$blobdbtype = 'BLOB'; //Name of blobs for this DB
break;
case 'mssql':
case 'odbc_mssql':
case 'mssql_n':
$clobdbtype = 'NOTPROCESSES'; //Name of clobs for this DB (under mssql flavours we don't process CLOBS)
$blobdbtype = 'IMAGE'; //Name of blobs for this DB
break;
default:
return; //Other DB doesn't need this two step to happen, prevent continue
}
/// Calculate the update sql condition
if (is_numeric($sqlcondition)) { /// If passing a number, it's the PK of the table (id)
$sqlcondition = 'id=' . $sqlcondition;
} else { /// Else, it's a formal standard SQL condition, we try to delete the WHERE in case it exists
$sqlcondition = trim(preg_replace('/^WHERE/is', '', trim($sqlcondition)));
}
/// Update all the clobs
if ($clobs) {
foreach ($clobs as $key => $value) {
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; }; /// Count the extra updates in PERF
if (!$db->UpdateClob($CFG->prefix.$table, $key, $value, $sqlcondition)) {
$status = false;
$statement = "UpdateClob('$CFG->prefix$table', '$key', '" . substr($value, 0, 100) . "...', '$sqlcondition')";
debugging($db->ErrorMsg() ."<br /><br />$statement");
if (!empty($CFG->dblogerror)) {
$debug=array_shift(debug_backtrace());
error_log("SQL ".$db->ErrorMsg()." in {$debug['file']} on line {$debug['line']}. STATEMENT: $statement");
}
}
}
}
/// Update all the blobs
if ($blobs) {
foreach ($blobs as $key => $value) {
if (defined('MDL_PERFDB')) { global $PERF ; $PERF->dbqueries++; }; /// Count the extra updates in PERF
if(!$db->UpdateBlob($CFG->prefix.$table, $key, $value, $sqlcondition)) {
$status = false;
$statement = "UpdateBlob('$CFG->prefix$table', '$key', '" . substr($value, 0, 100) . "...', '$sqlcondition')";
debugging($db->ErrorMsg() ."<br /><br />$statement");
if (!empty($CFG->dblogerror)) {
$debug=array_shift(debug_backtrace());
error_log("SQL ".$db->ErrorMsg()." in {$debug['file']} on line {$debug['line']}. STATEMENT: $statement");
}
}
}
}
return $status;
}
?>