Question

check_column( string $table_name,  string $col_name,  string $col_type,  bool $is_null = null,  mixed $key = null,  mixed $default = null,  mixed $extra = null )

Check column matches criteria.

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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

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参数

$table_name

(string) (Required) Table name

$col_name

(string) (Required) Column name

$col_type

(string) (Required) Column type

$is_null

(bool) (Optional) Check is null.

Default value: null

$key

(mixed) (Optional) Key info.

Default value: null

$default

(mixed) (Optional) Default value.

Default value: null

$extra

(mixed) (Optional) Extra value.

Default value: null

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返回值

(bool) True, if matches. False, if not matching.

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源代码

File: wp-admin/install-helper.php

function check_column($table_name, $col_name, $col_type, $is_null = null, $key = null, $default = 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 (($col_type != null) && ($row->Type != $col_type)) {
				++$diffs;
			}
			if (($is_null != null) && ($row->Null != $is_null)) {
				++$diffs;
			}
			if (($key != null) && ($row->Key  != $key)) {
				++$diffs;
			}
			if (($default != null) && ($row->Default != $default)) {
				++$diffs;
			}
			if (($extra != null) && ($row->Extra != $extra)) {
				++$diffs;
			}
			if ($diffs > 0) {
				return false;
			}
			return true;
		} // end if found our column
	}
	return false;
}

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更新日志

Version	description
1.0.0	Introduced.

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相关函数

Uses

• wp-includes/wp-db.php: wpdb::get_results()

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User Contributed Notes