wpdb::check_safe_collation()
Checks if the query is accessing a collation considered safe on the current version of MySQL.
Method of the class: wpdb{}
No Hooks.
Return
true|false
. True if the collation is safe, false if it isn't.
Usage
// protected - for code of main (parent) or child class $result = $this->check_safe_collation( $query );
- $query(string) (required)
- The query to check.
Changelog
Since 4.2.0 | Introduced. |
wpdb::check_safe_collation() wpdb::check safe collation code WP 6.5.2
protected function check_safe_collation( $query ) { if ( $this->checking_collation ) { return true; } // We don't need to check the collation for queries that don't read data. $query = ltrim( $query, "\r\n\t (" ); if ( preg_match( '/^(?:SHOW|DESCRIBE|DESC|EXPLAIN|CREATE)\s/i', $query ) ) { return true; } // All-ASCII queries don't need extra checking. if ( $this->check_ascii( $query ) ) { return true; } $table = $this->get_table_from_query( $query ); if ( ! $table ) { return false; } $this->checking_collation = true; $collation = $this->get_table_charset( $table ); $this->checking_collation = false; // Tables with no collation, or latin1 only, don't need extra checking. if ( false === $collation || 'latin1' === $collation ) { return true; } $table = strtolower( $table ); if ( empty( $this->col_meta[ $table ] ) ) { return false; } // If any of the columns don't have one of these collations, it needs more confidence checking. $safe_collations = array( 'utf8_bin', 'utf8_general_ci', 'utf8mb3_bin', 'utf8mb3_general_ci', 'utf8mb4_bin', 'utf8mb4_general_ci', ); foreach ( $this->col_meta[ $table ] as $col ) { if ( empty( $col->Collation ) ) { continue; } if ( ! in_array( $col->Collation, $safe_collations, true ) ) { return false; } } return true; }