public function DatabaseConnection_sqlsrv::addRangeToQuery in Drupal driver for SQL Server and SQL Azure 7

Same name and namespace in other branches

1. 7.3 sqlsrv/database.inc \DatabaseConnection_sqlsrv::addRangeToQuery()
2. 7.2 sqlsrv/database.inc \DatabaseConnection_sqlsrv::addRangeToQuery()

Internal function: add range options to a query.

This cannot be set protected because it is used in other parts of the database engine.

@status tested

1 call to DatabaseConnection_sqlsrv::addRangeToQuery()

DatabaseConnection_sqlsrv::queryRange in sqlsrv/database.inc

Override of DatabaseConnection::queryRange().

File

sqlsrv/database.inc, line 400

Database interface code for Microsoft SQL Server.

Class

DatabaseConnection_sqlsrv

Code

public function addRangeToQuery($query, $from, $count) {
  if ($from == 0) {

    // Easy case: just use a TOP query if we don't have to skip any rows.
    $query = preg_replace('/^\\s*SELECT(\\s*DISTINCT)?/Dsi', 'SELECT$1 TOP(' . $count . ')', $query);
  }
  else {

    // More complex case: use a TOP query to retrieve $from + $count rows, and
    // filter out the first $from rows using a window function.
    $query = preg_replace('/^\\s*SELECT(\\s*DISTINCT)?/Dsi', 'SELECT$1 TOP(' . ($from + $count) . ') ', $query);
    $query = '
        SELECT * FROM (
          SELECT sub2.*, ROW_NUMBER() OVER(ORDER BY sub2.__line2) AS __line3 FROM (
            SELECT 1 AS __line2, sub1.* FROM (' . $query . ') AS sub1
          ) as sub2
        ) AS sub3
        WHERE __line3 BETWEEN ' . ($from + 1) . ' AND ' . ($from + $count);
  }
  return $query;
}