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<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle 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 3 of the License, or
// (at your option) any later version.
//
// Moodle 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.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* Mysql specific SQL code generator.
*
* @package core_ddl
* @copyright 1999 onwards Martin Dougiamas http://dougiamas.com
* 2001-3001 Eloy Lafuente (stronk7) http://contiento.com
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
defined('MOODLE_INTERNAL') || die();
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
* overridden as needed to generate correct SQL.
*
* @package core_ddl
* @copyright 1999 onwards Martin Dougiamas http://dougiamas.com
* 2001-3001 Eloy Lafuente (stronk7) http://contiento.com
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
class mysql_sql_generator extends sql_generator {
// Only set values that are different from the defaults present in XMLDBgenerator
/** @var string Used to quote names. */
public $quote_string = '`';
/** @var string To define the default to set for NOT NULLs CHARs without default (null=do nothing).*/
public $default_for_char = '';
/** @var bool To specify if the generator must use some DEFAULT clause to drop defaults.*/
public $drop_default_value_required = true;
/** @var string The DEFAULT clause required to drop defaults.*/
public $drop_default_value = null;
/** @var string To force primary key names to one string (null=no force).*/
public $primary_key_name = '';
/** @var string Template to drop PKs. 'TABLENAME' and 'KEYNAME' will be replaced from this template.*/
public $drop_primary_key = 'ALTER TABLE TABLENAME DROP PRIMARY KEY';
/** @var string Template to drop UKs. 'TABLENAME' and 'KEYNAME' will be replaced from this template.*/
public $drop_unique_key = 'ALTER TABLE TABLENAME DROP KEY KEYNAME';
/** @var string Template to drop FKs. 'TABLENAME' and 'KEYNAME' will be replaced from this template.*/
public $drop_foreign_key = 'ALTER TABLE TABLENAME DROP FOREIGN KEY KEYNAME';
/** @var bool True if the generator needs to add extra code to generate the sequence fields.*/
public $sequence_extra_code = false;
/** @var string The particular name for inline sequences in this generator.*/
public $sequence_name = 'auto_increment';
public $add_after_clause = true; // Does the generator need to add the after clause for fields
/** @var string Characters to be used as concatenation operator.*/
public $concat_character = null;
/** @var string The SQL template to alter columns where the 'TABLENAME' and 'COLUMNSPECS' keywords are dynamically replaced.*/
public $alter_column_sql = 'ALTER TABLE TABLENAME MODIFY COLUMN COLUMNSPECS';
/** @var string SQL sentence to drop one index where 'TABLENAME', 'INDEXNAME' keywords are dynamically replaced.*/
public $drop_index_sql = 'ALTER TABLE TABLENAME DROP INDEX INDEXNAME';
/** @var string SQL sentence to rename one index where 'TABLENAME', 'OLDINDEXNAME' and 'NEWINDEXNAME' are dynamically replaced.*/
public $rename_index_sql = null;
/** @var string SQL sentence to rename one key 'TABLENAME', 'OLDKEYNAME' and 'NEWKEYNAME' are dynamically replaced.*/
public $rename_key_sql = null;
/** Maximum size of InnoDB row in Antelope file format */
const ANTELOPE_MAX_ROW_SIZE = 8126;
/**
* Reset a sequence to the id field of a table.
*
* @param xmldb_table|string $table name of table or the table object.
* @return array of sql statements
*/
public function getResetSequenceSQL($table) {
if ($table instanceof xmldb_table) {
$tablename = $table->getName();
} else {
$tablename = $table;
}
// 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 array("ALTER TABLE $this->prefix$tablename AUTO_INCREMENT = $value");
}
/**
* Calculate proximate row size when using InnoDB
* tables in Antelope row format.
*
* Note: the returned value is a bit higher to compensate for
* errors and changes of column data types.
*
* @deprecated since Moodle 2.9 MDL-49723 - please do not use this function any more.
*/
public function guess_antolope_row_size(array $columns) {
throw new coding_exception('guess_antolope_row_size() can not be used any more, please use guess_antelope_row_size() instead.');
}
/**
* Calculate proximate row size when using InnoDB tables in Antelope row format.
*
* Note: the returned value is a bit higher to compensate for errors and changes of column data types.
*
* @param xmldb_field[]|database_column_info[] $columns
* @return int approximate row size in bytes
*/
public function guess_antelope_row_size(array $columns) {
if (empty($columns)) {
return 0;
}
$size = 0;
$first = reset($columns);
if (count($columns) > 1) {
// Do not start with zero because we need to cover changes of field types and
// this calculation is most probably not be accurate.
$size += 1000;
}
if ($first instanceof xmldb_field) {
foreach ($columns as $field) {
switch ($field->getType()) {
case XMLDB_TYPE_TEXT:
$size += 768;
break;
case XMLDB_TYPE_BINARY:
$size += 768;
break;
case XMLDB_TYPE_CHAR:
$bytes = $field->getLength() * 3;
if ($bytes > 768) {
$bytes = 768;
}
$size += $bytes;
break;
default:
// Anything else is usually maximum 8 bytes.
$size += 8;
}
}
} else if ($first instanceof database_column_info) {
foreach ($columns as $column) {
switch ($column->meta_type) {
case 'X':
$size += 768;
break;
case 'B':
$size += 768;
break;
case 'C':
$bytes = $column->max_length * 3;
if ($bytes > 768) {
$bytes = 768;
}
$size += $bytes;
break;
default:
// Anything else is usually maximum 8 bytes.
$size += 8;
}
}
}
return $size;
}
/**
* Given one correct xmldb_table, returns the SQL statements
* to create it (inside one array).
*
* @param xmldb_table $xmldb_table An xmldb_table instance.
* @return array An array of SQL statements, starting with the table creation SQL followed
* by any of its comments, indexes and sequence creation SQL statements.
*/
public function getCreateTableSQL($xmldb_table) {
// First find out if want some special db engine.
$engine = $this->mdb->get_dbengine();
// Do we know collation?
$collation = $this->mdb->get_dbcollation();
// Do we need to use compressed format for rows?
$rowformat = "";
$size = $this->guess_antelope_row_size($xmldb_table->getFields());
if ($size > self::ANTELOPE_MAX_ROW_SIZE) {
if ($this->mdb->is_compressed_row_format_supported()) {
$rowformat = "\n ROW_FORMAT=Compressed";
}
}
$utf8mb4rowformat = $this->mdb->get_row_format_sql($engine, $collation);
$rowformat = ($utf8mb4rowformat == '') ? $rowformat : $utf8mb4rowformat;
$sqlarr = parent::getCreateTableSQL($xmldb_table);
// This is a very nasty hack that tries to use just one query per created table
// because MySQL is stupidly slow when modifying empty tables.
// Note: it is safer to inject everything on new lines because there might be some trailing -- comments.
$sqls = array();
$prevcreate = null;
$matches = null;
foreach ($sqlarr as $sql) {
if (preg_match('/^CREATE TABLE ([^ ]+)/', $sql, $matches)) {
$prevcreate = $matches[1];
$sql = preg_replace('/\s*\)\s*$/s', '/*keyblock*/)', $sql);
// Let's inject the extra MySQL tweaks here.
if ($engine) {
$sql .= "\n ENGINE = $engine";
}
if ($collation) {
if (strpos($collation, 'utf8_') === 0) {
$sql .= "\n DEFAULT CHARACTER SET utf8";
}
$sql .= "\n DEFAULT COLLATE = $collation ";
}
if ($rowformat) {
$sql .= $rowformat;
}
$sqls[] = $sql;
continue;
}
if ($prevcreate) {
if (preg_match('/^ALTER TABLE '.$prevcreate.' COMMENT=(.*)$/s', $sql, $matches)) {
$prev = array_pop($sqls);
$prev .= "\n COMMENT=$matches[1]";
$sqls[] = $prev;
continue;
}
if (preg_match('/^CREATE INDEX ([^ ]+) ON '.$prevcreate.' (.*)$/s', $sql, $matches)) {
$prev = array_pop($sqls);
if (strpos($prev, '/*keyblock*/')) {
$prev = str_replace('/*keyblock*/', "\n, KEY $matches[1] $matches[2]/*keyblock*/", $prev);
$sqls[] = $prev;
continue;
} else {
$sqls[] = $prev;
}
}
if (preg_match('/^CREATE UNIQUE INDEX ([^ ]+) ON '.$prevcreate.' (.*)$/s', $sql, $matches)) {
$prev = array_pop($sqls);
if (strpos($prev, '/*keyblock*/')) {
$prev = str_replace('/*keyblock*/', "\n, UNIQUE KEY $matches[1] $matches[2]/*keyblock*/", $prev);
$sqls[] = $prev;
continue;
} else {
$sqls[] = $prev;
}
}
}
$prevcreate = null;
$sqls[] = $sql;
}
foreach ($sqls as $key => $sql) {
$sqls[$key] = str_replace('/*keyblock*/', "\n", $sql);
}
return $sqls;
}
/**
* Given one xmldb_table and one xmldb_field, return the SQL statements needed to add the field to the table.
*
* @param xmldb_table $xmldb_table The table related to $xmldb_field.
* @param xmldb_field $xmldb_field The instance of xmldb_field to create the SQL from.
* @param string $skip_type_clause The type clause on alter columns, NULL by default.
* @param string $skip_default_clause The default clause on alter columns, NULL by default.
* @param string $skip_notnull_clause The null/notnull clause on alter columns, NULL by default.
* @return array The SQL statement for adding a field to the table.
*/
public function getAddFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause = NULL, $skip_default_clause = NULL, $skip_notnull_clause = NULL) {
$sqls = parent::getAddFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause, $skip_default_clause, $skip_notnull_clause);
if ($this->table_exists($xmldb_table)) {
$tablename = $xmldb_table->getName();
$size = $this->guess_antelope_row_size($this->mdb->get_columns($tablename));
$size += $this->guess_antelope_row_size(array($xmldb_field));
if ($size > self::ANTELOPE_MAX_ROW_SIZE) {
if ($this->mdb->is_compressed_row_format_supported()) {
$format = strtolower($this->mdb->get_row_format($tablename));
if ($format === 'compact' or $format === 'redundant') {
// Change the format before conversion so that we do not run out of space.
array_unshift($sqls, "ALTER TABLE {$this->prefix}$tablename ROW_FORMAT=Compressed");
}
}
}
}
return $sqls;
}
public function getAlterFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause = NULL, $skip_default_clause = NULL, $skip_notnull_clause = NULL)
{
$tablename = $xmldb_table->getName();
$dbcolumnsinfo = $this->mdb->get_columns($tablename);
if (($this->mdb->has_breaking_change_sqlmode()) &&
($dbcolumnsinfo[$xmldb_field->getName()]->meta_type == 'X') &&
($xmldb_field->getType() == XMLDB_TYPE_INTEGER)) {
// Ignore 1292 ER_TRUNCATED_WRONG_VALUE Truncated incorrect INTEGER value: '%s'.
$altercolumnsqlorig = $this->alter_column_sql;
$this->alter_column_sql = str_replace('ALTER TABLE', 'ALTER IGNORE TABLE', $this->alter_column_sql);
$result = parent::getAlterFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause, $skip_default_clause, $skip_notnull_clause);
// Restore the original ALTER SQL statement pattern.
$this->alter_column_sql = $altercolumnsqlorig;
return $result;
}
return parent::getAlterFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause, $skip_default_clause, $skip_notnull_clause);
}
/**
* Given one correct xmldb_table, returns the SQL statements
* to create temporary table (inside one array).
*
* @param xmldb_table $xmldb_table The xmldb_table object instance.
* @return array of sql statements
*/
public function getCreateTempTableSQL($xmldb_table) {
// Do we know collation?
$collation = $this->mdb->get_dbcollation();
$this->temptables->add_temptable($xmldb_table->getName());
$sqlarr = parent::getCreateTableSQL($xmldb_table);
// Let's inject the extra MySQL tweaks.
foreach ($sqlarr as $i=>$sql) {
if (strpos($sql, 'CREATE TABLE ') === 0) {
// We do not want the engine hack included in create table SQL.
$sqlarr[$i] = preg_replace('/^CREATE TABLE (.*)/s', 'CREATE TEMPORARY TABLE $1', $sql);
if ($collation) {
if (strpos($collation, 'utf8_') === 0) {
$sqlarr[$i] .= " DEFAULT CHARACTER SET utf8";
}
$sqlarr[$i] .= " DEFAULT COLLATE $collation ROW_FORMAT=DYNAMIC";
}
}
}
return $sqlarr;
}
/**
* Given one correct xmldb_table, returns the SQL statements
* to drop it (inside one array).
*
* @param xmldb_table $xmldb_table The table to drop.
* @return array SQL statement(s) for dropping the specified table.
*/
public function getDropTableSQL($xmldb_table) {
$sqlarr = parent::getDropTableSQL($xmldb_table);
if ($this->temptables->is_temptable($xmldb_table->getName())) {
$sqlarr = preg_replace('/^DROP TABLE/', "DROP TEMPORARY TABLE", $sqlarr);
}
return $sqlarr;
}
/**
* Given one XMLDB Type, length and decimals, returns the DB proper SQL type.
*
* @param int $xmldb_type The xmldb_type defined constant. XMLDB_TYPE_INTEGER and other XMLDB_TYPE_* constants.
* @param int $xmldb_length The length of that data type.
* @param int $xmldb_decimals The decimal places of precision of the data type.
* @return string The DB defined data type.
*/
public function getTypeSQL($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 .= '(' . $xmldb_length . ')';
if ($collation = $this->mdb->get_dbcollation()) {
if (strpos($collation, 'utf8_') === 0) {
$dbtype .= " CHARACTER SET utf8";
}
$dbtype .= " COLLATE $collation";
}
break;
case XMLDB_TYPE_TEXT:
$dbtype = 'LONGTEXT';
if ($collation = $this->mdb->get_dbcollation()) {
if (strpos($collation, 'utf8_') === 0) {
$dbtype .= " CHARACTER SET utf8";
}
$dbtype .= " COLLATE $collation";
}
break;
case XMLDB_TYPE_BINARY:
$dbtype = 'LONGBLOB';
break;
case XMLDB_TYPE_DATETIME:
$dbtype = 'DATETIME';
}
return $dbtype;
}
/**
* Given one xmldb_table and one xmldb_field, return the SQL statements needed to add its default
* (usually invoked from getModifyDefaultSQL()
*
* @param xmldb_table $xmldb_table The xmldb_table object instance.
* @param xmldb_field $xmldb_field The xmldb_field object instance.
* @return array Array of SQL statements to create a field's default.
*/
public function getCreateDefaultSQL($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).
*
* @param xmldb_table $xmldb_table The table related to $xmldb_field.
* @param xmldb_field $xmldb_field The instance of xmldb_field to get the renamed field from.
* @param string $newname The new name to rename the field to.
* @return array The SQL statements for renaming the field.
*/
public function getRenameFieldSQL($xmldb_table, $xmldb_field, $newname) {
// NOTE: MySQL is pretty different from the standard to justify this overloading.
// 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
$xmldb_field_clone->setName($newname);
$fieldsql = $this->getFieldSQL($xmldb_table, $xmldb_field_clone);
$sql = 'ALTER TABLE ' . $this->getTableName($xmldb_table) . ' CHANGE ' .
$this->getEncQuoted($xmldb_field->getName()) . ' ' . $fieldsql;
return array($sql);
}
/**
* Given one xmldb_table and one xmldb_field, return the SQL statements needed to drop its default
* (usually invoked from getModifyDefaultSQL()
*
* Note that this method may be dropped in future.
*
* @param xmldb_table $xmldb_table The xmldb_table object instance.
* @param xmldb_field $xmldb_field The xmldb_field object instance.
* @return array Array of SQL statements to create a field's default.
*
* @todo MDL-31147 Moodle 2.1 - Drop getDropDefaultSQL()
*/
public function getDropDefaultSQL($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 (array of statements) needed to add one comment to the table.
*
* @param xmldb_table $xmldb_table The xmldb_table object instance.
* @return array Array of SQL statements to add one comment to the table.
*/
function getCommentSQL ($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 object name and it's type (pk, uk, fk, ck, ix, uix, seq, trg).
*
* (MySQL requires the whole xmldb_table object to be specified, so we add it always)
*
* This is invoked from getNameForObject().
* Only some DB have this implemented.
*
* @param string $object_name The object's name to check for.
* @param string $type The object's type (pk, uk, fk, ck, ix, uix, seq, trg).
* @param string $table_name The table's name to check in
* @return bool If such name is currently in use (true) or no (false)
*/
public function isNameInUse($object_name, $type, $table_name) {
switch($type) {
case 'ix':
case 'uix':
// First of all, check table exists
$metatables = $this->mdb->get_tables();
if (isset($metatables[$table_name])) {
// Fetch all the indexes in the table
if ($indexes = $this->mdb->get_indexes($table_name)) {
// 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
* @return array An array of database specific reserved words
*/
public static function getReservedWords() {
// This file contains the reserved words for MySQL databases.
$reserved_words = array (
// From http://dev.mysql.com/doc/refman/6.0/en/reserved-words.html.
'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',
// Added in MySQL 8.0, compared to MySQL 5.7:
// https://dev.mysql.com/doc/refman/8.0/en/keywords.html#keywords-new-in-current-series.
'_filename', 'admin', 'cume_dist', 'dense_rank', 'empty', 'except', 'first_value', 'grouping', 'groups',
'json_table', 'lag', 'last_value', 'lead', 'nth_value', 'ntile',
'of', 'over', 'percent_rank', 'persist', 'persist_only', 'rank', 'recursive', 'row_number',
'system', 'window'
);
return $reserved_words;
}
}