Creates a table in the database, if it doesn’t already exist.

This method checks for an existing database and creates a new one if it’s not already present. It doesn’t rely on MySQL’s "IF NOT EXISTS" statement, but chooses to query all tables first and then run the SQL statement creating the table.

$table_name string Required

Database table name.

$create_ddl string Required

SQL statement to create table.

bool True on success or if the table already exists. False on failure.

File: wp-admin/includes/upgrade.php. View all references

function maybe_create_table( $table_name, $create_ddl ) {
	global $wpdb;

	$query = $wpdb->prepare( 'SHOW TABLES LIKE %s', $wpdb->esc_like( $table_name ) );

	if ( $wpdb->get_var( $query ) === $table_name ) {
		return true;
	}

	// Didn't find it, so try to create it.
	$wpdb->query( $create_ddl );

	// We cannot directly tell that whether this succeeded!
	if ( $wpdb->get_var( $query ) === $table_name ) {
		return true;
	}

	return false;
}