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filter is not described

pre_get_col_charset filter-hook . WP 4.2.0

Filters the column charset value before the DB is checked.

Passing a non-null value to the filter will short-circuit checking the DB for the charset, returning that value instead.

Usage

add_filter( 'pre_get_col_charset', 'filter_function_name_1841', 10, 3 );
function filter_function_name_1841( $charset, $table, $column ){
	// filter...

	return $charset;
}
$charset(string)
The character set to use.
Default: null
$table(string)
The name of the table being checked.
$column(string)
The name of the column being checked.

Where the hook is called

wpdb::get_col_charset()
wp-includes/wp-db.php 2659
$charset = apply_filters( 'pre_get_col_charset', null, $table, $column );

Where the hook is used (in WP core)

Does not used.