File Content: class-wp-meta-query.php <?php /** * Meta API: WP_Meta_Query class * * @package WordPress * @subpackage Meta * @since 4.4.0 */ /** * Core class used to implement meta queries for the Meta API. * * Used for generating SQL clauses that filter a primary query according to metadata keys and values. * * WP_Meta_Query is a helper that allows primary query classes, such as WP_Query and WP_User_Query, * * to filter their results by object metadata, by generating `JOIN` and `WHERE` subclauses to be attached * to the primary SQL query string. * * @since 3.2.0 */ class WP_Meta_Query { /** * Array of metadata queries. * * See WP_Meta_Query::__construct() for information on meta query arguments. * * @since 3.2.0 * @var array */ public $queries = array(); /** * The relation between the queries. Can be one of 'AND' or 'OR'. * * @since 3.2.0 * @var string */ public $relation; /** * Database table to query for the metadata. * * @since 4.1.0 * @var string */ public $meta_table; /** * Column in meta_table that represents the ID of the object the metadata belongs to. * * @since 4.1.0 * @var string */ public $meta_id_column; /** * Database table that where the metadata's objects are stored (eg $wpdb->users). * * @since 4.1.0 * @var string */ public $primary_table; /** * Column in primary_table that represents the ID of the object. * * @since 4.1.0 * @var string */ public $primary_id_column; /** * A flat list of table aliases used in JOIN clauses. * * @since 4.1.0 * @var array */ protected $table_aliases = array(); /** * A flat list of clauses, keyed by clause 'name'. * * @since 4.2.0 * @var array */ protected $clauses = array(); /** * Whether the query contains any OR relations. * * @since 4.3.0 * @var bool */ protected $has_or_relation = false; /** * Constructor. * * @since 3.2.0 * @since 4.2.0 Introduced support for naming query clauses by associative array keys. * * * @param array $meta_query { * Array of meta query clauses. When first-order clauses or sub-clauses use strings as * their array keys, they may be referenced in the 'orderby' parameter of the parent query. * * @type string $relation Optional. The MySQL keyword used to join * the clauses of the query. Accepts 'AND', or 'OR'. Default 'AND'. * @type array { * Optional. An array of first-order clause parameters, or another fully-formed meta query. * * @type string $key Meta key to filter by. * @type string $value Meta value to filter by. * @type string $compare MySQL operator used for comparing the $value. Accepts '=', * '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE', * 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN', 'REGEXP', * 'NOT REGEXP', 'RLIKE', 'EXISTS' or 'NOT EXISTS'. * Default is 'IN' when `$value` is an array, '=' otherwise. * @type string $type MySQL data type that the meta_value column will be CAST to for * comparisons. Accepts 'NUMERIC', 'BINARY', 'CHAR', 'DATE', * 'DATETIME', 'DECIMAL', 'SIGNED', 'TIME', or 'UNSIGNED'. * Default is 'CHAR'. * } * } */ public function __construct( $meta_query = false ) { if ( !$meta_query ) return; if ( isset( $meta_query['relation'] ) && strtoupper( $meta_query['relation'] ) == 'OR' ) { $this->relation = 'OR'; } else { $this->relation = 'AND'; } $this->queries = $this->sanitize_query( $meta_query ); } /** * Ensure the 'meta_query' argument passed to the class constructor is well-formed. * * Eliminates empty items and ensures that a 'relation' is set. * * @since 4.1.0 * * @param array $queries Array of query clauses. * @return array Sanitized array of query clauses. */ public function sanitize_query( $queries ) { $clean_queries = array(); if ( ! is_array( $queries ) ) { return $clean_queries; } foreach ( $queries as $key => $query ) { if ( 'relation' === $key ) { $relation = $query; } elseif ( ! is_array( $query ) ) { continue; // First-order clause. } elseif ( $this->is_first_order_clause( $query ) ) { if ( isset( $query['value'] ) && array() === $query['value'] ) { unset( $query['value'] ); } $clean_queries[ $key ] = $query; // Otherwise, it's a nested query, so we recurse. } else { $cleaned_query = $this->sanitize_query( $query ); if ( ! empty( $cleaned_query ) ) { $clean_queries[ $key ] = $cleaned_query; } } } if ( empty( $clean_queries ) ) { return $clean_queries; } // Sanitize the 'relation' key provided in the query. if ( isset( $relation ) && 'OR' === strtoupper( $relation ) ) { $clean_queries['relation'] = 'OR'; $this->has_or_relation = true; /* * If there is only a single clause, call the relation 'OR'. * This value will not actually be used to join clauses, but it * simplifies the logic around combining key-only queries. */ } elseif ( 1 === count( $clean_queries ) ) { $clean_queries['relation'] = 'OR'; // Default to AND. } else { $clean_queries['relation'] = 'AND'; } return $clean_queries; } /** * Determine whether a query clause is first-order. * * A first-order meta query clause is one that has either a 'key' or * a 'value' array key. * * @since 4.1.0 * * @param array $query Meta query arguments. * @return bool Whether the query clause is a first-order clause. */ protected function is_first_order_clause( $query ) { return isset( $query['key'] ) || isset( $query['value'] ); } /** * Constructs a meta query based on 'meta_*' query vars * * @since 3.2.0 * * @param array $qv The query variables */ public function parse_query_vars( $qv ) { $meta_query = array(); /* * For orderby=meta_value to work correctly, simple query needs to be * first (so that its table join is against an unaliased meta table) and * needs to be its own clause (so it doesn't interfere with the logic of * the rest of the meta_query). */ $primary_meta_query = array(); foreach ( array( 'key', 'compare', 'type' ) as $key ) { if ( ! empty( $qv[ "meta_$key" ] ) ) { $primary_meta_query[ $key ] = $qv[ "meta_$key" ]; } } // WP_Query sets 'meta_value' = '' by default. if ( isset( $qv['meta_value'] ) && '' !== $qv['meta_value'] && ( ! is_array( $qv['meta_value'] ) || $qv['meta_value'] ) ) { $primary_meta_query['value'] = $qv['meta_value']; } $existing_meta_query = isset( $qv['meta_query'] ) && is_array( $qv['meta_query'] ) ? $qv['meta_query'] : array(); if ( ! empty( $primary_meta_query ) && ! empty( $existing_meta_query ) ) { $meta_query = array( 'relation' => 'AND', $primary_meta_query, $existing_meta_query, ); } elseif ( ! empty( $primary_meta_query ) ) { $meta_query = array( $primary_meta_query, ); } elseif ( ! empty( $existing_meta_query ) ) { $meta_query = $existing_meta_query; } $this->__construct( $meta_query ); } /** * Return the appropriate alias for the given meta type if applicable. * * @since 3.7.0 * * @param string $type MySQL type to cast meta_value. * @return string MySQL type. */ public function get_cast_for_type( $type = '' ) { if ( empty( $type ) ) return 'CHAR'; $meta_type = strtoupper( $type ); if ( ! preg_match( '/^(?:BINARY|CHAR|DATE|DATETIME|SIGNED|UNSIGNED|TIME|NUMERIC(?:\(\d+(?:,\s?\d+)?\))?|DECIMAL(?:\(\d+(?:,\s?\d+)?\))?)$/', $meta_type ) ) return 'CHAR'; if ( 'NUMERIC' == $meta_type ) $meta_type = 'SIGNED'; return $meta_type; } /** * Generates SQL clauses to be appended to a main query. * * @since 3.2.0 * * @param string $type Type of meta, eg 'user', 'post'. * @param string $primary_table Database table where the object being filtered is stored (eg wp_users). * @param string $primary_id_column ID column for the filtered object in $primary_table. * @param object $context Optional. The main query object. * @return false|array { * Array containing JOIN and WHERE SQL clauses to append to the main query. * * @type string $join SQL fragment to append to the main JOIN clause. * @type string $where SQL fragment to append to the main WHERE clause. * } */ public function get_sql( $type, $primary_table, $primary_id_column, $context = null ) { if ( ! $meta_table = _get_meta_table( $type ) ) { return false; } $this->table_aliases = array(); $this->meta_table = $meta_table; $this->meta_id_column = sanitize_key( $type . '_id' ); $this->primary_table = $primary_table; $this->primary_id_column = $primary_id_column; $sql = $this->get_sql_clauses(); /* * If any JOINs are LEFT JOINs (as in the case of NOT EXISTS), then all JOINs should * be LEFT. Otherwise posts with no metadata will be excluded from results. */ if ( false !== strpos( $sql['join'], 'LEFT JOIN' ) ) { $sql['join'] = str_replace( 'INNER JOIN', 'LEFT JOIN', $sql['join'] ); } /** * Filters the meta query's generated SQL. * * @since 3.1.0 * * @param array $clauses Array containing the query's JOIN and WHERE clauses. * @param array $queries Array of meta queries. * @param string $type Type of meta. * @param string $primary_table Primary table. * @param string $primary_id_column Primary column ID. * @param object $context The main query object. */ return apply_filters_ref_array( 'get_meta_sql', array( $sql, $this->queries, $type, $primary_table, $primary_id_column, $context ) ); } /** * Generate SQL clauses to be appended to a main query. * * Called by the public WP_Meta_Query::get_sql(), this method is abstracted * out to maintain parity with the other Query classes. * * @since 4.1.0 * * @return array { * Array containing JOIN and WHERE SQL clauses to append to the main query. * * @type string $join SQL fragment to append to the main JOIN clause. * @type string $where SQL fragment to append to the main WHERE clause. * } */ protected function get_sql_clauses() { /* * $queries are passed by reference to get_sql_for_query() for recursion. * To keep $this->queries unaltered, pass a copy. */ $queries = $this->queries; $sql = $this->get_sql_for_query( $queries ); if ( ! empty( $sql['where'] ) ) { $sql['where'] = ' AND ' . $sql['where']; } return $sql; } /** * Generate SQL clauses for a single query array. * * If nested subqueries are found, this method recurses the tree to * produce the properly nested SQL. * * @since 4.1.0 * * @param array $query Query to parse (passed by reference). * @param int $depth Optional. Number of tree levels deep we currently are. * Used to calculate indentation. Default 0. * @return array { * Array containing JOIN and WHERE SQL clauses to append to a single query array. * * @type string $join SQL fragment to append to the main JOIN clause. * @type string $where SQL fragment to append to the main WHERE clause. * } */ protected function get_sql_for_query( &$query, $depth = 0 ) { $sql_chunks = array( 'join' => array(), 'where' => array(), ); $sql = array( 'join' => '', 'where' => '', ); $indent = ''; for ( $i = 0; $i < $depth; $i++ ) { $indent .= " "; } foreach ( $query as $key => &$clause ) { if ( 'relation' === $key ) { $relation = $query['relation']; } elseif ( is_array( $clause ) ) { // This is a first-order clause. if ( $this->is_first_order_clause( $clause ) ) { $clause_sql = $this->get_sql_for_clause( $clause, $query, $key ); $where_count = count( $clause_sql['where'] ); if ( ! $where_count ) { $sql_chunks['where'][] = ''; } elseif ( 1 === $where_count ) { $sql_chunks['where'][] = $clause_sql['where'][0]; } else { $sql_chunks['where'][] = '( ' . implode( ' AND ', $clause_sql['where'] ) . ' )'; } $sql_chunks['join'] = array_merge( $sql_chunks['join'], $clause_sql['join'] ); // This is a subquery, so we recurse. } else { $clause_sql = $this->get_sql_for_query( $clause, $depth + 1 ); $sql_chunks['where'][] = $clause_sql['where']; $sql_chunks['join'][] = $clause_sql['join']; } } } // Filter to remove empties. $sql_chunks['join'] = array_filter( $sql_chunks['join'] ); $sql_chunks['where'] = array_filter( $sql_chunks['where'] ); if ( empty( $relation ) ) { $relation = 'AND'; } // Filter duplicate JOIN clauses and combine into a single string. if ( ! empty( $sql_chunks['join'] ) ) { $sql['join'] = implode( ' ', array_unique( $sql_chunks['join'] ) ); } // Generate a single WHERE clause with proper brackets and indentation. if ( ! empty( $sql_chunks['where'] ) ) { $sql['where'] = '( ' . "\n " . $indent . implode( ' ' . "\n " . $indent . $relation . ' ' . "\n " . $indent, $sql_chunks['where'] ) . "\n" . $indent . ')'; } return $sql; } /** * Generate SQL JOIN and WHERE clauses for a first-order query clause. * * "First-order" means that it's an array with a 'key' or 'value'. * * @since 4.1.0 * * @global wpdb $wpdb WordPress database abstraction object. * * @param array $clause Query clause (passed by reference). * @param array $parent_query Parent query array. * @param string $clause_key Optional. The array key used to name the clause in the original `$meta_query` * parameters. If not provided, a key will be generated automatically. * @return array { * Array containing JOIN and WHERE SQL clauses to append to a first-order query. * * @type string $join SQL fragment to append to the main JOIN clause. * @type string $where SQL fragment to append to the main WHERE clause. * } */ public function get_sql_for_clause( &$clause, $parent_query, $clause_key = '' ) { global $wpdb; $sql_chunks = array( 'where' => array(), 'join' => array(), ); if ( isset( $clause['compare'] ) ) { $clause['compare'] = strtoupper( $clause['compare'] ); } else { $clause['compare'] = isset( $clause['value'] ) && is_array( $clause['value'] ) ? 'IN' : '='; } if ( ! in_array( $clause['compare'], array( '=', '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN', 'EXISTS', 'NOT EXISTS', 'REGEXP', 'NOT REGEXP', 'RLIKE' ) ) ) { $clause['compare'] = '='; } $meta_compare = $clause['compare']; // First build the JOIN clause, if one is required. $join = ''; // We prefer to avoid joins if possible. Look for an existing join compatible with this clause. $alias = $this->find_compatible_table_alias( $clause, $parent_query ); if ( false === $alias ) { $i = count( $this->table_aliases ); $alias = $i ? 'mt' . $i : $this->meta_table; // JOIN clauses for NOT EXISTS have their own syntax. if ( 'NOT EXISTS' === $meta_compare ) { $join .= " LEFT JOIN $this->meta_table"; $join .= $i ? " AS $alias" : ''; $join .= $wpdb->prepare( " ON ($this->primary_table.$this->primary_id_column = $alias.$this->meta_id_column AND $alias.meta_key = %s )", $clause['key'] ); // All other JOIN clauses. } else { $join .= " INNER JOIN $this->meta_table"; $join .= $i ? " AS $alias" : ''; $join .= " ON ( $this->primary_table.$this->primary_id_column = $alias.$this->meta_id_column )"; } $this->table_aliases[] = $alias; $sql_chunks['join'][] = $join; } // Save the alias to this clause, for future siblings to find. $clause['alias'] = $alias; // Determine the data type. $_meta_type = isset( $clause['type'] ) ? $clause['type'] : ''; $meta_type = $this->get_cast_for_type( $_meta_type ); $clause['cast'] = $meta_type; // Fallback for clause keys is the table alias. Key must be a string. if ( is_int( $clause_key ) || ! $clause_key ) { $clause_key = $clause['alias']; } // Ensure unique clause keys, so none are overwritten. $iterator = 1; $clause_key_base = $clause_key; while ( isset( $this->clauses[ $clause_key ] ) ) { $clause_key = $clause_key_base . '-' . $iterator; $iterator++; } // Store the clause in our flat array. $this->clauses[ $clause_key ] =& $clause; // Next, build the WHERE clause. // meta_key. if ( array_key_exists( 'key', $clause ) ) { if ( 'NOT EXISTS' === $meta_compare ) { $sql_chunks['where'][] = $alias . '.' . $this->meta_id_column . ' IS NULL'; } else { $sql_chunks['where'][] = $wpdb->prepare( "$alias.meta_key = %s", trim( $clause['key'] ) ); } } // meta_value. if ( array_key_exists( 'value', $clause ) ) { $meta_value = $clause['value']; if ( in_array( $meta_compare, array( 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN' ) ) ) { if ( ! is_array( $meta_value ) ) { $meta_value = preg_split( '/[,\s]+/', $meta_value ); } } else { $meta_value = trim( $meta_value ); } switch ( $meta_compare ) { case 'IN' : case 'NOT IN' : $meta_compare_string = '(' . substr( str_repeat( ',%s', count( $meta_value ) ), 1 ) . ')'; $where = $wpdb->prepare( $meta_compare_string, $meta_value ); break; case 'BETWEEN' : case 'NOT BETWEEN' : $meta_value = array_slice( $meta_value, 0, 2 ); $where = $wpdb->prepare( '%s AND %s', $meta_value ); break; case 'LIKE' : case 'NOT LIKE' : $meta_value = '%' . $wpdb->esc_like( $meta_value ) . '%'; $where = $wpdb->prepare( '%s', $meta_value ); break; // EXISTS with a value is interpreted as '='. case 'EXISTS' : $meta_compare = '='; $where = $wpdb->prepare( '%s', $meta_value ); break; // 'value' is ignored for NOT EXISTS. case 'NOT EXISTS' : $where = ''; break; default : $where = $wpdb->prepare( '%s', $meta_value ); break; } if ( $where ) { if ( 'CHAR' === $meta_type ) { $sql_chunks['where'][] = "$alias.meta_value {$meta_compare} {$where}"; } else { $sql_chunks['where'][] = "CAST($alias.meta_value AS {$meta_type}) {$meta_compare} {$where}"; } } } /* * Multiple WHERE clauses (for meta_key and meta_value) should * be joined in parentheses. */ if ( 1 < count( $sql_chunks['where'] ) ) { $sql_chunks['where'] = array( '( ' . implode( ' AND ', $sql_chunks['where'] ) . ' )' ); } return $sql_chunks; } /** * Get a flattened list of sanitized meta clauses. * * This array should be used for clause lookup, as when the table alias and CAST type must be determined for * a value of 'orderby' corresponding to a meta clause. * * @since 4.2.0 * * @return array Meta clauses. */ public function get_clauses() { return $this->clauses; } /** * Identify an existing table alias that is compatible with the current * query clause. * * We avoid unnecessary table joins by allowing each clause to look for * an existing table alias that is compatible with the query that it * needs to perform. * * An existing alias is compatible if (a) it is a sibling of `$clause` * (ie, it's under the scope of the same relation), and (b) the combination * of operator and relation between the clauses allows for a shared table join. * In the case of WP_Meta_Query, this only applies to 'IN' clauses that are * connected by the relation 'OR'. * * @since 4.1.0 * * @param array $clause Query clause. * @param array $parent_query Parent query of $clause. * @return string|bool Table alias if found, otherwise false. */ protected function find_compatible_table_alias( $clause, $parent_query ) { $alias = false; foreach ( $parent_query as $sibling ) { // If the sibling has no alias yet, there's nothing to check. if ( empty( $sibling['alias'] ) ) { continue; } // We're only interested in siblings that are first-order clauses. if ( ! is_array( $sibling ) || ! $this->is_first_order_clause( $sibling ) ) { continue; } $compatible_compares = array(); // Clauses connected by OR can share joins as long as they have "positive" operators. if ( 'OR' === $parent_query['relation'] ) { $compatible_compares = array( '=', 'IN', 'BETWEEN', 'LIKE', 'REGEXP', 'RLIKE', '>', '>=', '<', '<=' ); // Clauses joined by AND with "negative" operators share a join only if they also share a key. } elseif ( isset( $sibling['key'] ) && isset( $clause['key'] ) && $sibling['key'] === $clause['key'] ) { $compatible_compares = array( '!=', 'NOT IN', 'NOT LIKE' ); } $clause_compare = strtoupper( $clause['compare'] ); $sibling_compare = strtoupper( $sibling['compare'] ); if ( in_array( $clause_compare, $compatible_compares ) && in_array( $sibling_compare, $compatible_compares ) ) { $alias = preg_replace( '/\W/', '_', $sibling['alias'] ); break; } } /** * Filters the table alias identified as compatible with the current clause. * * @since 4.1.0 * * @param string|bool $alias Table alias, or false if none was found. * @param array $clause First-order query clause. * @param array $parent_query Parent of $clause. * @param object $this WP_Meta_Query object. */ return apply_filters( 'meta_query_find_compatible_table_alias', $alias, $clause, $parent_query, $this ) ; } /** * Checks whether the current query has any OR relations. * * In some cases, the presence of an OR relation somewhere in the query will require * the use of a `DISTINCT` or `GROUP BY` keyword in the `SELECT` clause. The current * method can be used in these cases to determine whether such a clause is necessary. * * @since 4.3.0 * * @return bool True if the query contains any `OR` relations, otherwise false. */ public function has_or_relation() { return $this->has_or_relation; } } Submit