Merge "Add a maintenance script for populating pp_sortkey"
[lhc/web/wiklou.git] / includes / libs / rdbms / database / Database.php
index 9e91592..723a4a6 100644 (file)
@@ -1802,8 +1802,33 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
                }
 
                # Split database and table into proper variables.
-               # We reverse the explode so that database.table and table both output
-               # the correct table.
+               list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
+
+               # Quote $table and apply the prefix if not quoted.
+               # $tableName might be empty if this is called from Database::replaceVars()
+               $tableName = "{$prefix}{$table}";
+               if ( $format === 'quoted'
+                       && !$this->isQuotedIdentifier( $tableName )
+                       && $tableName !== ''
+               ) {
+                       $tableName = $this->addIdentifierQuotes( $tableName );
+               }
+
+               # Quote $schema and $database and merge them with the table name if needed
+               $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
+               $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
+
+               return $tableName;
+       }
+
+       /**
+        * Get the table components needed for a query given the currently selected database
+        *
+        * @param string $name Table name in the form of db.schema.table, db.table, or table
+        * @return array (DB name or "" for default, schema name, table prefix, table name)
+        */
+       protected function qualifiedTableComponents( $name ) {
+               # We reverse the explode so that database.table and table both output the correct table.
                $dbDetails = explode( '.', $name, 3 );
                if ( count( $dbDetails ) == 3 ) {
                        list( $database, $schema, $table ) = $dbDetails;
@@ -1833,21 +1858,7 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
                        }
                }
 
-               # Quote $table and apply the prefix if not quoted.
-               # $tableName might be empty if this is called from Database::replaceVars()
-               $tableName = "{$prefix}{$table}";
-               if ( $format === 'quoted'
-                       && !$this->isQuotedIdentifier( $tableName )
-                       && $tableName !== ''
-               ) {
-                       $tableName = $this->addIdentifierQuotes( $tableName );
-               }
-
-               # Quote $schema and $database and merge them with the table name if needed
-               $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
-               $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
-
-               return $tableName;
+               return [ $database, $schema, $prefix, $table ];
        }
 
        /**
@@ -2470,6 +2481,77 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
                return '(' . implode( $glue, $sqls ) . ')';
        }
 
+       public function unionConditionPermutations(
+               $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__,
+               $options = [], $join_conds = []
+       ) {
+               // First, build the Cartesian product of $permute_conds
+               $conds = [ [] ];
+               foreach ( $permute_conds as $field => $values ) {
+                       if ( !$values ) {
+                               // Skip empty $values
+                               continue;
+                       }
+                       $values = array_unique( $values ); // For sanity
+                       $newConds = [];
+                       foreach ( $conds as $cond ) {
+                               foreach ( $values as $value ) {
+                                       $cond[$field] = $value;
+                                       $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
+                               }
+                       }
+                       $conds = $newConds;
+               }
+
+               $extra_conds = $extra_conds === '' ? [] : (array)$extra_conds;
+
+               // If there's just one condition and no subordering, hand off to
+               // selectSQLText directly.
+               if ( count( $conds ) === 1 &&
+                       ( !isset( $options['INNER ORDER BY'] ) || !$this->unionSupportsOrderAndLimit() )
+               ) {
+                       return $this->selectSQLText(
+                               $table, $vars, $conds[0] + $extra_conds, $fname, $options, $join_conds
+                       );
+               }
+
+               // Otherwise, we need to pull out the order and limit to apply after
+               // the union. Then build the SQL queries for each set of conditions in
+               // $conds. Then union them together (using UNION ALL, because the
+               // product *should* already be distinct).
+               $orderBy = $this->makeOrderBy( $options );
+               $limit = isset( $options['LIMIT'] ) ? $options['LIMIT'] : null;
+               $offset = isset( $options['OFFSET'] ) ? $options['OFFSET'] : false;
+               $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
+               if ( !$this->unionSupportsOrderAndLimit() ) {
+                       unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
+               } else {
+                       if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
+                               $options['ORDER BY'] = $options['INNER ORDER BY'];
+                       }
+                       if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
+                               // We need to increase the limit by the offset rather than
+                               // using the offset directly, otherwise it'll skip incorrectly
+                               // in the subqueries.
+                               $options['LIMIT'] = $limit + $offset;
+                               unset( $options['OFFSET'] );
+                       }
+               }
+
+               $sqls = [];
+               foreach ( $conds as $cond ) {
+                       $sqls[] = $this->selectSQLText(
+                               $table, $vars, $cond + $extra_conds, $fname, $options, $join_conds
+                       );
+               }
+               $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
+               if ( $limit !== null ) {
+                       $sql = $this->limitResult( $sql, $limit, $offset );
+               }
+
+               return $sql;
+       }
+
        public function conditional( $cond, $trueVal, $falseVal ) {
                if ( is_array( $cond ) ) {
                        $cond = $this->makeList( $cond, self::LIST_AND );