WordPress at a glance
function is not described

maybe_add_column() WP 1.3.0

Adds column to a database table if it doesn't already exist.

  • Global. wpdb. $wpdb

No Hooks.

Return

true/false. True if already exists or on successful completion, false on error.

Usage

maybe_add_column( $table_name, $column_name, $create_ddl );
$table_name(string) (required)
The table name to modify.
$column_name(string) (required)
The column name to add to the table.
$create_ddl(string) (required)
The SQL statement used to add the column.

Code of maybe add column: wp-admin/includes/upgrade.php VER 5.1.1

<?php
function maybe_add_column( $table_name, $column_name, $create_ddl ) {
	global $wpdb;
	foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) {
		if ( $column == $column_name ) {
			return true;
		}
	}

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

	// We cannot directly tell that whether this succeeded!
	foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) {
		if ( $column == $column_name ) {
			return true;
		}
	}
	return false;
}