Use table aliases for columns in SQL generated by WP_Date_Query.

The use of non-aliased column names (eg 'post_date' instead of 'wp_posts.post_date')
in WP_Date_Query causes SQL notices and other failures when queries involve
table joins, such as date_query combined with tax_query or meta_query. This
changeset modifies WP_Date_Query::validate_column() to add the table alias when
it can be detected from the column name (ie, in the case of core columns).

A side effect of this change is that it is now possible to use WP_Date_Query
to build WHERE clauses across multiple tables, though there is currently no
core support for the automatic generation of the necessary JOIN clauses. See

Props ew_holmes, wonderboymusic, neoxx, Viper007Bond, boonebgorges.
Fixes #25775.
Built from https://develop.svn.wordpress.org/trunk@29933


git-svn-id: http://core.svn.wordpress.org/trunk@29685 1a063a9b-81f0-0310-95a4-ce76da25c4cd
This commit is contained in:
Boone Gorges 2014-10-17 01:20:21 +00:00
parent 50f1b45594
commit fcc82fd671

View File

@ -435,6 +435,11 @@ class WP_Date_Query {
/**
* Validates a column name parameter.
*
* Column names without a table prefix (like 'post_date') are checked against a whitelist of
* known tables, and then, if found, have a table prefix (such as 'wp_posts.') prepended.
* Prefixed column names (such as 'wp_posts.post_date') bypass this whitelist check,
* and are only sanitized to remove illegal characters.
*
* @since 3.7.0
* @access public
*
@ -442,22 +447,53 @@ class WP_Date_Query {
* @return string A validated column name value.
*/
public function validate_column( $column ) {
global $wpdb;
$valid_columns = array(
'post_date', 'post_date_gmt', 'post_modified',
'post_modified_gmt', 'comment_date', 'comment_date_gmt'
);
/**
* Filter the list of valid date query columns.
*
* @since 3.7.0
*
* @param array $valid_columns An array of valid date query columns. Defaults are 'post_date', 'post_date_gmt',
* 'post_modified', 'post_modified_gmt', 'comment_date', 'comment_date_gmt'
*/
if ( ! in_array( $column, apply_filters( 'date_query_valid_columns', $valid_columns ) ) )
$column = 'post_date';
return $column;
// Attempt to detect a table prefix.
if ( false === strpos( $column, '.' ) ) {
/**
* Filter the list of valid date query columns.
*
* @since 3.7.0
*
* @param array $valid_columns An array of valid date query columns. Defaults
* are 'post_date', 'post_date_gmt', 'post_modified',
* 'post_modified_gmt', 'comment_date', 'comment_date_gmt'
*/
if ( ! in_array( $column, apply_filters( 'date_query_valid_columns', $valid_columns ) ) ) {
$column = 'post_date';
}
$known_columns = array(
$wpdb->posts => array(
'post_date',
'post_date_gmt',
'post_modified',
'post_modified_gmt',
),
$wpdb->comments => array(
'comment_date',
'comment_date_gmt',
),
);
// If it's a known column name, add the appropriate table prefix.
foreach ( $known_columns as $table_name => $table_columns ) {
if ( in_array( $column, $table_columns ) ) {
$column = $table_name . '.' . $column;
break;
}
}
}
// Remove unsafe characters.
return preg_replace( '/[^a-zA-Z0-9_$\.]/', '', $column );
}
/**