moodle/lib/dml/mssql_adodb_moodle_database.php

410 lines
15 KiB
PHP

<?php //$Id$
require_once($CFG->libdir.'/dml/moodle_database.php');
require_once($CFG->libdir.'/dml/adodb_moodle_database.php');
/**
* MSSQL database class using adodb backend
* @package dml
*/
class mssql_adodb_moodle_database extends adodb_moodle_database {
/**
* Ungly mssql hack needed for temp table names starting with '#'
*/
public $temptables;
public function connect($dbhost, $dbuser, $dbpass, $dbname, $prefix, array $dboptions=null) {
if ($prefix == '' and !$this->external) {
//Enforce prefixes for everybody but mysql
throw new dml_exception('prefixcannotbeempty', $this->get_dbfamily());
}
return parent::connect($dbhost, $dbuser, $dbpass, $dbname, $prefix, $dboptions);
}
/**
* Detects if all needed PHP stuff installed.
* Do not connect to connect to db if this test fails.
* @return mixed true if ok, string if something
*/
public function driver_installed() {
if (!function_exists('mssql_connect')) {
return get_string('mssqlextensionisnotpresentinphp', 'install');
}
return true;
}
protected function preconfigure_dbconnection() {
if (!defined('ADODB_ASSOC_CASE')) {
define ('ADODB_ASSOC_CASE', 2);
}
}
protected function configure_dbconnection() {
$this->adodb->SetFetchMode(ADODB_FETCH_ASSOC);
/// No need to set charset. It must be specified in the driver conf
/// Allow quoted identifiers
$sql = "SET QUOTED_IDENTIFIER ON";
$this->query_start($sql, null, SQL_QUERY_AUX);
$rs = $this->adodb->Execute($sql);
$this->query_end($rs);
/// Force ANSI nulls so the NULL check was done by IS NULL and NOT IS NULL
/// instead of equal(=) and distinct(<>) simbols
$sql = "SET ANSI_NULLS ON";
$this->query_start($sql, null, SQL_QUERY_AUX);
$rs = $this->adodb->Execute($sql);
$this->query_end($rs);
return true;
}
/**
* Returns database family type
* @return string db family name (mysql, postgres, mssql, oracle, etc.)
*/
public function get_dbfamily() {
return 'mssql';
}
/**
* Returns database type
* @return string db type mysql, mysqli, postgres7
*/
protected function get_dbtype() {
return 'mssql';
}
/**
* Returns localised database description
* Note: can be used before connect()
* @return string
*/
public function get_configuration_hints() {
$str = get_string('databasesettingssub_mssql', 'install');
$str .= "<p style='text-align:right'><a href=\"javascript:void(0)\" ";
$str .= "onclick=\"return window.open('http://docs.moodle.org/en/Installing_MSSQL_for_PHP')\"";
$str .= ">";
$str .= '<img src="pix/docs.gif' . '" alt="Docs" class="iconhelp" />';
$str .= get_string('moodledocslink', 'install') . '</a></p>';
return $str;
}
/**
* Converts short table name {tablename} to real table name
* @param string sql
* @return string sql
*/
protected function fix_table_names($sql) {
// look for temporary tables, they must start with #
if (preg_match_all('/\{([a-z][a-z0-9_]*)\}/', $sql, $matches)) {
foreach($matches[0] as $key=>$match) {
$name = $matches[1][$key];
if (empty($this->temptables[$name])) {
$sql = str_replace($match, $this->prefix.$name, $sql);
} else {
$sql = str_replace($match, '#'.$this->prefix.$name, $sql);
}
}
}
return $sql;
}
/**
* Returns supported query parameter types
* @return bitmask
*/
protected function allowed_param_types() {
return SQL_PARAMS_QM;
}
public function sql_ceil($fieldname) {
return ' CEILING(' . $fieldname . ')';
}
public function sql_cast_char2int($fieldname, $text=false) {
if (!$text) {
return ' CAST(' . $fieldname . ' AS INT) ';
} else {
return ' CAST(' . $this->sql_compare_text($fieldname) . ' AS INT) ';
}
}
public function sql_order_by_text($fieldname, $numchars=32) {
return ' CONVERT(varchar, ' . $fieldname . ', ' . $numchars . ')';
}
/**
* Returns the SQL for returning searching one string for the location of another.
*/
public function sql_position($needle, $haystack) {
return "CHARINDEX(($needle), ($haystack))";
}
public function sql_isempty($tablename, $fieldname, $nullablefield, $textfield) {
if ($textfield) {
return $this->sql_compare_text($fieldname)." = '' ";
} else {
return " $fieldname = '' ";
}
}
/**
* Returns the proper substr() function for each DB.
* NOTE: this was originally returning only function name
*
* @param string $expr some string field, no aggregates
* @param mixed $start integer or expresion evaluating to int
* @param mixed $length optional integer or expresion evaluating to int
* @return string sql fragment
*/
public function sql_substr($expr, $start, $length=false) {
if ($length === false) {
return "SUBSTRING($expr, $start, (LEN($expr) - $start + 1))";
} else {
return "SUBSTRING($expr, $start, $length)";
}
}
/**
* 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
*
* @param string $table The database table to be checked against.
* @param object $dataobject An object with contents equal to fieldname=>fieldvalue. Must have an entry for 'id' to map to the table specified.
* @param bool true means repeated updates expected
* @return bool true
* @throws dml_exception if error
*/
public function update_record($table, $dataobject, $bulk=false) {
if (!is_object($dataobject)) {
$dataobject = (object)$dataobject;
}
$columns = $this->get_columns($table);
$cleaned = array();
$blobs = array();
foreach ($dataobject as $field=>$value) {
if (!isset($columns[$field])) { /// Non-existing table field, skip it
continue;
}
$column = $columns[$field];
if ($column->meta_type == 'B') { /// BLOBs (IMAGE) columns need to be updated apart
if (!is_null($value)) { /// If value not null, add it to the list of BLOBs to update later
$blobs[$field] = $value;
$value = null; /// Set the default value to be inserted in first instance
}
} else if ($column->meta_type == 'X') { /// MSSQL doesn't cast from int to text, so if text column
if (is_numeric($value)) { /// and is numeric value
$value = (string)$value; /// cast to string
}
} else if (is_bool($value)) {
$value = (int)$value; // prevent "false" problems
} else if ($value === '') {
if ($column->meta_type == 'I' or $column->meta_type == 'F' or $column->meta_type == 'N') {
$value = 0; // prevent '' problems in numeric fields
}
}
$cleaned[$field] = $value;
}
if (empty($blobs)) { /// Without BLOBs, execute the raw update and return
return $this->update_record_raw($table, $cleaned, $bulk);
}
/// We have BLOBs to postprocess, execute the raw update and then update blobs
$this->update_record_raw($table, $cleaned, $bulk);
foreach ($blobs as $key=>$value) {
$this->query_start('--adodb-UpdateBlob', null, SQL_QUERY_UPDATE);
$result = $this->adodb->UpdateBlob($this->prefix.$table, $key, $value, "id = {$dataobject->id}");
$this->query_end($result);
}
return true;
}
/**
* Set a single field in every table row where the select statement evaluates to true.
*
* @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 $select A fragment of SQL to be used in a where clause in the SQL call.
* @param array $params array of sql parameters
* @return bool true
* @throws dml_exception if error
*/
public function set_field_select($table, $newfield, $newvalue, $select, array $params=null) {
if (is_null($params)) {
$params = array();
}
list($select, $params, $type) = $this->fix_sql_params($select, $params);
$columns = $this->get_columns($table);
$column = $columns[$newfield];
if ($column->meta_type == 'B') { /// If the column is a BLOB (IMAGE)
/// Update BLOB column and return
$select = $this->emulate_bound_params($select, $params); // adodb does not use bound parameters for blob updates :-(
$this->query_start('--adodb-UpdateBlob', null, SQL_QUERY_UPDATE);
$result = $this->adodb->UpdateBlob($this->prefix.$table, $newfield, $newvalue, $select);
$this->query_end($result);
}
/// Arrived here, normal update (without BLOBs)
if (is_null($newvalue)) {
$newfield = "$newfield = NULL";
} else {
if ($column->meta_type == 'X') { /// MSSQL doesn't cast from int to text, so if text column
if (is_numeric($newvalue)) { /// and is numeric value
$newvalue = (string)$newvalue; /// cast to string in PHP
}
} else if (is_bool($newvalue)) {
$newvalue = (int)$newvalue; // prevent "false" problems
} else if ($newvalue === '') {
if ($column->meta_type == 'I' or $column->meta_type == 'F' or $column->meta_type == 'N') {
$newvalue = 0; // prevent '' problems in numeric fields
}
}
$newfield = "$newfield = ?";
array_unshift($params, $newvalue); // add as first param
}
$sql = "UPDATE {$this->prefix}$table SET $newfield WHERE $select";
$this->query_start($sql, $params, SQL_QUERY_UPDATE);
$rs = $this->adodb->Execute($sql, $params);
$this->query_end($rs);
$rs->Close();
return true;
}
/**
* Insert a record into a table and return the "id" field if required,
* Some conversions and safety checks are carried out. Lobs are supported.
* If the return ID isn't required, then this just reports success as true/false.
* $data is an object containing needed data
* @param string $table The database table to be inserted into
* @param object $data 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 bool $bulk true means repeated inserts expected
* @return mixed true or new id
* @throws dml_exception if error
*/
public function insert_record($table, $dataobject, $returnid=true, $bulk=false) {
if (!is_object($dataobject)) {
$dataobject = (object)$dataobject;
}
unset($dataobject->id);
$columns = $this->get_columns($table);
$cleaned = array();
$blobs = array();
foreach ($dataobject as $field=>$value) {
if (!isset($columns[$field])) { /// Non-existing table field, skip it
continue;
}
$column = $columns[$field];
if ($column->meta_type == 'B') { /// BLOBs (IMAGE) columns need to be updated apart
if (!is_null($value)) { /// If value not null, add it to the list of BLOBs to update later
$blobs[$field] = $value;
$value = null; /// Set the default value to be inserted in first instance
}
} else if ($column->meta_type == 'X') { /// MSSQL doesn't cast from int to text, so if text column
if (is_numeric($value)) { /// and is numeric value
$value = (string)$value; /// cast to string
}
} else if (is_bool($value)) {
$value = (int)$value; // prevent "false" problems
} else if ($value === '') {
if ($column->meta_type == 'I' or $column->meta_type == 'F' or $column->meta_type == 'N') {
$value = 0; // prevent '' problems in numeric fields
}
}
$cleaned[$field] = $value;
}
if (empty($blobs)) { /// Without BLOBs, execute the raw insert and return
return $this->insert_record_raw($table, $cleaned, $returnid, $bulk);
}
/// We have BLOBs to postprocess, insert the raw record fetching the id to be used later
$id = $this->insert_record_raw($table, $cleaned, true, $bulk);
foreach ($blobs as $key=>$value) {
$this->query_start('--adodb-UpdateBlob', null, SQL_QUERY_UPDATE);
$result = $this->adodb->UpdateBlob($this->prefix.$table, $key, $value, "id = $id");
$this->query_end($result);
}
return ($returnid ? $id : true);
}
/**
* Import a record into a table, id field is required.
* Basic safety checks only. Lobs are supported.
* @param string $table name of database table to be inserted into
* @param mixed $dataobject object or array with fields in the record
* @return bool true
* @throws dml_exception if error
*/
public function import_record($table, $dataobject) {
$dataobject = (object)$dataobject;
$columns = $this->get_columns($table);
$cleaned = array();
$blobs = array();
foreach ($dataobject as $field=>$value) {
if (!isset($columns[$field])) { // Non-existing table field, skip it
continue;
}
$column = $columns[$field];
if ($column->meta_type == 'B') { // BLOBs (IMAGE) columns need to be updated apart
if (!is_null($value)) { // If value not null, add it to the list of BLOBs to update later
$blobs[$field] = $value;
$value = null; // Set the default value to be inserted in first instance
}
} else if ($column->meta_type == 'X') { // MSSQL doesn't cast from int to text, so if text column
if (is_numeric($value)) { // and is numeric value
$value = (string)$value; // cast to string
}
}
$cleaned[$field] = $value;
}
$this->insert_record_raw($table, $cleaned, false, true, true);
if (empty($blobs)) {
return true;
}
/// We have BLOBs to postprocess
foreach ($blobs as $key=>$value) {
$this->query_start('--adodb-UpdateBlob', null, SQL_QUERY_UPDATE);
$result = $this->adodb->UpdateBlob($this->prefix.$table, $key, $value, "id = $id");
$this->query_end($result);
}
return true;
}
}