WordPress at a glance
function is not described

maybe_drop_column() WP 1.0.0

Drop column from database table, if it exists.

  • Global. wpdb. $wpdb WordPress database abstraction object.

No Hooks.

Return

true/false. False on failure, true on success or doesn't exist.

Usage

maybe_drop_column( $table_name, $column_name, $drop_ddl );
$table_name(string) (required)
Table name
$column_name(string) (required)
Column name
$drop_ddl(string) (required)
SQL statement to drop column.

Code of maybe drop column: wp-admin/install-helper.php VER 5.0.3

<?php
function maybe_drop_column($table_name, $column_name, $drop_ddl) {
	global $wpdb;
	foreach ($wpdb->get_col("DESC $table_name",0) as $column ) {
		if ($column == $column_name) {

			// Found it, so try to drop it.
			$wpdb->query($drop_ddl);

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