moodle/lib/ddl/mysql_sql_generator.php
stronk7 d09af2e19f MDL-18547 mysql floats - only none/both params (length & decimals) syntax is
allowed. So, if decimals are missing, enforce 0 if length is defined. Merged
from 19_STABLE
2009-05-11 15:11:23 +00:00

472 lines
20 KiB
PHP

<?php // $Id$
///////////////////////////////////////////////////////////////////////////
// //
// NOTICE OF COPYRIGHT //
// //
// Moodle - Modular Object-Oriented Dynamic Learning Environment //
// http://moodle.com //
// //
// Copyright (C) 1999 onwards Martin Dougiamas http://dougiamas.com //
// (C) 2001-3001 Eloy Lafuente (stronk7) http://contiento.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 //
// //
///////////////////////////////////////////////////////////////////////////
require_once($CFG->libdir.'/ddl/sql_generator.php');
/// This class generate SQL code to be used against MySQL
/// It extends XMLDBgenerator so everything can be
/// overriden as needed to generate correct SQL.
class mysql_sql_generator extends sql_generator {
/// Only set values that are different from the defaults present in XMLDBgenerator
public $quote_string = '`'; // String used to quote names
public $default_for_char = ''; // To define the default to set for NOT NULLs CHARs without default (null=do nothing)
public $drop_default_value_required = true; //To specify if the generator must use some DEFAULT clause to drop defaults
public $drop_default_value = NULL; //The DEFAULT clause required to drop defaults
public $primary_key_name = ''; //To force primary key names to one string (null=no force)
public $drop_primary_key = 'ALTER TABLE TABLENAME DROP PRIMARY KEY'; // Template to drop PKs
// with automatic replace for TABLENAME and KEYNAME
public $drop_unique_key = 'ALTER TABLE TABLENAME DROP KEY KEYNAME'; // Template to drop UKs
// with automatic replace for TABLENAME and KEYNAME
public $drop_foreign_key = 'ALTER TABLE TABLENAME DROP FOREIGN KEY KEYNAME'; // Template to drop FKs
// with automatic replace for TABLENAME and KEYNAME
public $sequence_extra_code = false; //Does the generator need to add extra code to generate the sequence fields
public $sequence_name = 'auto_increment'; //Particular name for inline sequences in this generator
public $enum_extra_code = false; //Does the generator need to add extra code to generate code for the enums in the table
public $add_after_clause = true; // Does the generator need to add the after clause for fields
public $concat_character = null; //Characters to be used as concatenation operator. If not defined
//MySQL CONCAT function will be use
public $alter_column_sql = 'ALTER TABLE TABLENAME MODIFY COLUMN COLUMNSPECS'; //The SQL template to alter columns
public $drop_index_sql = 'ALTER TABLE TABLENAME DROP INDEX INDEXNAME'; //SQL sentence to drop one index
//TABLENAME, INDEXNAME are dinamically replaced
public $rename_index_sql = null; //SQL sentence to rename one index (MySQL doesn't support this!)
//TABLENAME, OLDINDEXNAME, NEWINDEXNAME are dinamically replaced
public $rename_key_sql = null; //SQL sentence to rename one key (MySQL doesn't support this!)
//TABLENAME, OLDKEYNAME, NEWKEYNAME are dinamically replaced
/**
* Creates one new XMLDBmysql
*/
public function __construct($mdb) {
parent::__construct($mdb);
}
/**
* Reset a sequence to the id field of a table.
* @param string $table name of table
* @return bool success
*/
public function reset_sequence($table) {
if (is_string($table)) {
$tablename = $table;
} else {
$tablename = $table->getName();
}
// From http://dev.mysql.com/doc/refman/5.0/en/alter-table.html
$value = (int)$this->mdb->get_field_sql('SELECT MAX(id) FROM {'.$tablename.'}');
$value++;
return $this->mdb->change_database_structure("ALTER TABLE $this->prefix$tablename AUTO_INCREMENT = $value");
}
/**
* Given one xmldb_table, check if it exists in DB (true/false)
*
* @param mixed the table to be searched (string name or xmldb_table instance)
* @param bool temp table (might need different checks)
* @return boolean true/false
*/
public function table_exists($table, $temptable=false) {
global $CFG;
if (!$temptable) {
return parent::table_exists($table, $temptable);
}
if (is_string($table)) {
$tablename = $table;
} else {
/// Calculate the name of the table
$tablename = $table->getName();
}
/// Do this function silenty (to avoid output in install/upgrade process)
$olddbdebug = $this->mdb->get_debug();
$this->mdb->set_debug(false);
$oldcfgdebug = $CFG->debug;
$CFG->debug = 0;
// ugly hack - mysql does not list temporary tables :-(
// this polutes the db log with errors :-(
// TODO: is there a better way?
try {
$result = $this->mdb->execute("DESCRIBE {".$tablename."}");
} catch (Exception $e) {
$result = false;
}
if ($result === false) {
$exists = false;
} else {
$exists = true;
}
/// Re-set original debug
$this->mdb->set_debug($olddbdebug);
$CFG->debug = $oldcfgdebug;
return $exists;
}
/**
* Given one correct xmldb_table, returns the SQL statements
* to create temporary table (inside one array)
*/
public function getCreateTempTableSQL($xmldb_table) {
$sqlarr = $this->getCreateTableSQL($xmldb_table);
$sqlarr = preg_replace('/^CREATE TABLE (.*)/s', 'CREATE TEMPORARY TABLE $1 TYPE=MyISAM', $sqlarr);
return $sqlarr;
}
/**
* Given one correct xmldb_table and the new name, returns the SQL statements
* to drop it (inside one array)
*/
public function getDropTempTableSQL($xmldb_table) {
$sqlarr = parent::getDropTableSQL($xmldb_table);
$sqlarr = preg_replace('/^DROP TABLE/', "DROP TEMPORARY TABLE", $sqlarr);
return $sqlarr;
}
/**
* Given one XMLDB Type, lenght and decimals, returns the DB proper SQL type
*/
public function getTypeSQL($xmldb_type, $xmldb_length=null, $xmldb_decimals=null) {
switch ($xmldb_type) {
case XMLDB_TYPE_INTEGER: // From http://mysql.com/doc/refman/5.0/en/numeric-types.html!
if (empty($xmldb_length)) {
$xmldb_length = 10;
}
if ($xmldb_length > 9) {
$dbtype = 'BIGINT';
} else if ($xmldb_length > 6) {
$dbtype = 'INT';
} else if ($xmldb_length > 4) {
$dbtype = 'MEDIUMINT';
} else if ($xmldb_length > 2) {
$dbtype = 'SMALLINT';
} else {
$dbtype = 'TINYINT';
}
$dbtype .= '(' . $xmldb_length . ')';
break;
case XMLDB_TYPE_NUMBER:
$dbtype = $this->number_type;
if (!empty($xmldb_length)) {
$dbtype .= '(' . $xmldb_length;
if (!empty($xmldb_decimals)) {
$dbtype .= ',' . $xmldb_decimals;
}
$dbtype .= ')';
}
break;
case XMLDB_TYPE_FLOAT:
$dbtype = 'DOUBLE';
if (!empty($xmldb_decimals)) {
if ($xmldb_decimals < 6) {
$dbtype = 'FLOAT';
}
}
if (!empty($xmldb_length)) {
$dbtype .= '(' . $xmldb_length;
if (!empty($xmldb_decimals)) {
$dbtype .= ',' . $xmldb_decimals;
} else {
$dbtype .= ', 0'; // In MySQL, if length is specified, decimals are mandatory for FLOATs
}
$dbtype .= ')';
}
break;
case XMLDB_TYPE_CHAR:
$dbtype = 'VARCHAR';
if (empty($xmldb_length)) {
$xmldb_length='255';
}
$dbtype .= '(' . $xmldb_length . ')';
break;
case XMLDB_TYPE_TEXT:
if (empty($xmldb_length)) {
$xmldb_length = 'small';
}
if ($xmldb_length == 'small') {
$dbtype = 'TEXT';
} else if ($xmldb_length == 'medium') {
$dbtype = 'MEDIUMTEXT';
} else {
$dbtype = 'LONGTEXT';
}
break;
case XMLDB_TYPE_BINARY:
if (empty($xmldb_length)) {
$xmldb_length = 'small';
}
if ($xmldb_length == 'small') {
$dbtype = 'BLOB';
} else if ($xmldb_length == 'medium') {
$dbtype = 'MEDIUMBLOB';
} else {
$dbtype = 'LONGBLOB';
}
break;
case XMLDB_TYPE_DATETIME:
$dbtype = 'DATETIME';
}
return $dbtype;
}
/**
* Given one xmldb_table and one xmldb_field, return the SQL statements needded to create its enum
* (usually invoked from getModifyEnumSQL()
*/
public function getCreateEnumSQL($xmldb_table, $xmldb_field) {
/// For MySQL, just alter the field
return $this->getAlterFieldSQL($xmldb_table, $xmldb_field);
}
/**
* Given one xmldb_table and one xmldb_field, return the SQL statements needded to drop its enum
* (usually invoked from getModifyEnumSQL()
*
* TODO: Moodle 2.1 - drop in Moodle 2.1
*/
public function getDropEnumSQL($xmldb_table, $xmldb_field) {
/// Let's introspect to know if there is one enum
if ($check_constraints = $this->getCheckConstraintsFromDB($xmldb_table, $xmldb_field)) {
/// For MySQL, just alter the field
return $this->getAlterFieldSQL($xmldb_table, $xmldb_field);
} else {
return array(); /// Enum not found. Nothing to do
}
}
/**
* Given one xmldb_table and one xmldb_field, return the SQL statements needded to create its default
* (usually invoked from getModifyDefaultSQL()
*/
public function getCreateDefaultSQL($xmldb_table, $xmldb_field) {
/// Just a wrapper over the getAlterFieldSQL() function for MySQL that
/// is capable of handling defaults
return $this->getAlterFieldSQL($xmldb_table, $xmldb_field);
}
/**
* Given one correct xmldb_field and the new name, returns the SQL statements
* to rename it (inside one array)
* MySQL is pretty diferent from the standard to justify this oveloading
*/
public function getRenameFieldSQL($xmldb_table, $xmldb_field, $newname) {
/// Need a clone of xmldb_field to perform the change leaving original unmodified
$xmldb_field_clone = clone($xmldb_field);
/// Change the name of the field to perform the change
$xmldb_field_clone->setName($xmldb_field_clone->getName() . ' ' . $newname);
$fieldsql = $this->getFieldSQL($xmldb_field_clone);
$sql = 'ALTER TABLE ' . $this->getTableName($xmldb_table) . ' CHANGE ' . $fieldsql;
return array($sql);
}
/**
* Given one xmldb_table and one xmldb_field, return the SQL statements needded to drop its default
* (usually invoked from getModifyDefaultSQL()
*/
public function getDropDefaultSQL($xmldb_table, $xmldb_field) {
/// Just a wrapper over the getAlterFieldSQL() function for MySQL that
/// is capable of handling defaults
return $this->getAlterFieldSQL($xmldb_table, $xmldb_field);
}
/**
* Returns the code (in array) needed to add one comment to the table
*/
function getCommentSQL ($xmldb_table) {
$comment = '';
if ($xmldb_table->getComment()) {
$comment .= 'ALTER TABLE ' . $this->getTableName($xmldb_table);
$comment .= " COMMENT='" . $this->addslashes(substr($xmldb_table->getComment(), 0, 60)) . "'";
}
return array($comment);
}
/**
* Given one xmldb_table returns one array with all the check constrainsts
* in the table (fetched from DB)
* Optionally the function allows one xmldb_field to be specified in
* order to return only the check constraints belonging to one field.
* Each element contains the name of the constraint and its description
* If no check constraints are found, returns an empty array
* MySQL doesn't have check constraints in this implementation, but
* we return them based on the enum fields in the table
*
* TODO: Moodle 2.1 - drop in Moodle 2.1
*/
public function getCheckConstraintsFromDB($xmldb_table, $xmldb_field = null) {
$tablename = $xmldb_table->getName($xmldb_table);
/// Fetch all the columns in the table
if (!$columns = $this->mdb->get_columns($tablename, false)) {
return array();
}
/// Filter by the required field if specified
if ($xmldb_field) {
$filter = $xmldb_field->getName();
if (!isset($columns[$filter])) {
return array();
}
$column = ($columns[$filter]);
if (!empty($column->enums)) {
$result = new object;
$result->name = $filter;
$result->description = implode(', ', $column->enums);
return array($result);
} else {
return array();
}
} else {
$results = array();
/// Iterate over columns searching for enums
foreach ($columns as $key => $column) {
/// Enum found, let's add it to the constraints list
if (!empty($column->enums)) {
$result = new object;
$result->name = $key;
$result->description = implode(', ', $column->enums);
$results[$key] = $result;
}
}
return $results;
}
}
/**
* Given one object name and it's type (pk, uk, fk, ck, ix, uix, seq, trg)
* return if such name is currently in use (true) or no (false)
* (invoked from getNameForObject()
*/
public function isNameInUse($object_name, $type, $table_name) {
/// Calculate the real table name
$xmldb_table = new xmldb_table($table_name);
$tname = $this->getTableName($xmldb_table);
switch($type) {
case 'ix':
case 'uix':
/// First of all, check table exists
$metatables = $this->mdb->get_tables();
if (isset($metatables[$tname])) {
/// Fetch all the indexes in the table
if ($indexes = $this->mdb->get_indexes($tname)) {
/// Look for existing index in array
if (isset($indexes[$object_name])) {
return true;
}
}
}
break;
}
return false; //No name in use found
}
/**
* Returns an array of reserved words (lowercase) for this DB
*/
public static function getReservedWords() {
/// This file contains the reserved words for MySQL databases
/// from http://dev.mysql.com/doc/refman/6.0/en/reserved-words.html
$reserved_words = array (
'accessible', 'add', 'all', 'alter', 'analyze', 'and', 'as', 'asc',
'asensitive', 'before', 'between', 'bigint', 'binary',
'blob', 'both', 'by', 'call', 'cascade', 'case', 'change',
'char', 'character', 'check', 'collate', 'column',
'condition', 'connection', 'constraint', 'continue',
'convert', 'create', 'cross', 'current_date', 'current_time',
'current_timestamp', 'current_user', 'cursor', 'database',
'databases', 'day_hour', 'day_microsecond',
'day_minute', 'day_second', 'dec', 'decimal', 'declare',
'default', 'delayed', 'delete', 'desc', 'describe',
'deterministic', 'distinct', 'distinctrow', 'div', 'double',
'drop', 'dual', 'each', 'else', 'elseif', 'enclosed', 'escaped',
'exists', 'exit', 'explain', 'false', 'fetch', 'float', 'float4',
'float8', 'for', 'force', 'foreign', 'from', 'fulltext', 'grant',
'group', 'having', 'high_priority', 'hour_microsecond',
'hour_minute', 'hour_second', 'if', 'ignore', 'in', 'index',
'infile', 'inner', 'inout', 'insensitive', 'insert', 'int', 'int1',
'int2', 'int3', 'int4', 'int8', 'integer', 'interval', 'into', 'is',
'iterate', 'join', 'key', 'keys', 'kill', 'leading', 'leave', 'left',
'like', 'limit', 'linear', 'lines', 'load', 'localtime', 'localtimestamp',
'lock', 'long', 'longblob', 'longtext', 'loop', 'low_priority', 'master_heartbeat_period',
'master_ssl_verify_server_cert', 'match', 'mediumblob', 'mediumint', 'mediumtext',
'middleint', 'minute_microsecond', 'minute_second',
'mod', 'modifies', 'natural', 'not', 'no_write_to_binlog',
'null', 'numeric', 'on', 'optimize', 'option', 'optionally',
'or', 'order', 'out', 'outer', 'outfile', 'overwrite', 'precision', 'primary',
'procedure', 'purge', 'raid0', 'range', 'read', 'read_only', 'read_write', 'reads', 'real',
'references', 'regexp', 'release', 'rename', 'repeat', 'replace',
'require', 'restrict', 'return', 'revoke', 'right', 'rlike', 'schema',
'schemas', 'second_microsecond', 'select', 'sensitive',
'separator', 'set', 'show', 'smallint', 'soname', 'spatial',
'specific', 'sql', 'sqlexception', 'sqlstate', 'sqlwarning',
'sql_big_result', 'sql_calc_found_rows', 'sql_small_result',
'ssl', 'starting', 'straight_join', 'table', 'terminated', 'then',
'tinyblob', 'tinyint', 'tinytext', 'to', 'trailing', 'trigger', 'true',
'undo', 'union', 'unique', 'unlock', 'unsigned', 'update',
'upgrade', 'usage', 'use', 'using', 'utc_date', 'utc_time',
'utc_timestamp', 'values', 'varbinary', 'varchar', 'varcharacter',
'varying', 'when', 'where', 'while', 'with', 'write', 'x509',
'xor', 'year_month', 'zerofill'
);
return $reserved_words;
}
}
?>