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check_column( string $table_name, string $col_name, string $col_type, bool $is_null = null, mixed $key = null, mixed $default_value = null, mixed $extra = null ): bool
Checks that database table column matches the criteria.
Description
Uses the SQL DESC for retrieving the table info for the column. It will help understand the parameters, if you do more research on what column information is returned by the SQL statement. Pass in null to skip checking that criteria.
Column names returned from DESC table are case sensitive and are listed: Field Type Null Key Default Extra
Parameters
$table_namestring Required-
Database table name.
$col_namestring Required-
Table column name.
$col_typestring Required-
Table column type.
$is_nullbool Optional-
Check is null.
Default:
null $keymixed Optional-
Key info.
Default:
null $default_valuemixed Optional-
Default value.
Default:
null $extramixed Optional-
Extra value.
Default:
null
Return
bool True, if matches. False, if not matching.
Source
File: wp-admin/install-helper.php. View all references
function check_column( $table_name, $col_name, $col_type, $is_null = null, $key = null, $default_value = null, $extra = null ) {
global $wpdb;
$diffs = 0;
$results = $wpdb->get_results( "DESC $table_name" );
foreach ( $results as $row ) {
if ( $row->Field === $col_name ) {
// Got our column, check the params.
if ( ( null !== $col_type ) && ( $row->Type !== $col_type ) ) {
++$diffs;
}
if ( ( null !== $is_null ) && ( $row->Null !== $is_null ) ) {
++$diffs;
}
if ( ( null !== $key ) && ( $row->Key !== $key ) ) {
++$diffs;
}
if ( ( null !== $default_value ) && ( $row->Default !== $default_value ) ) {
++$diffs;
}
if ( ( null !== $extra ) && ( $row->Extra !== $extra ) ) {
++$diffs;
}
if ( $diffs > 0 ) {
return false;
}
return true;
} // End if found our column.
}
return false;
}
Related
Uses
| Uses | Description |
|---|---|
| wpdb::get_results() wp-includes/class-wpdb.php | Retrieves an entire SQL result set from the database (i.e., many rows). |
Changelog
| Version | Description |
|---|---|
| 1.0.0 | Introduced. |
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Licensed under the GNU GPLv2+ License.
https://developer.wordpress.org/reference/functions/check_column