/**
* Executes multiple SQL queries and returns an array
* of results.
*
* @param array $arSqls Array of SQL queries
* @return array Array of query results
*/
protected function queryMultiple($arSqls)
{
$arSM = $this->query->getSolutionModifier();
if ($arSM['limit'] === null && $arSM['offset'] === null) {
$nOffset = 0;
$nLimit = null;
$nSql = 0;
} else {
$offsetter = new SparqlEngineDb_Offsetter($this->dbConn, $this->query);
list($nSql, $nOffset) = $offsetter->determineOffset($arSqls);
$nLimit = $arSM['limit'];
}
$nCount = 0;
$arResults = array();
foreach ($arSqls as $nId => $arSql) {
if ($nId < $nSql) {
continue;
}
if ($nLimit != null) {
$nCurrentLimit = $nLimit - $nCount;
} else {
$nCurrentLimit = null;
}
$dbResult = $this->queryDb($arSql, $nOffset, $nCurrentLimit);
$nCount += $dbResult->RowCount();
$arResults[] = $dbResult;
$nOffset = 0;
if ($nLimit !== null && $nCount >= $nLimit) {
break;
}
}
return $arResults;
//return array_map(array($this, 'queryDb'), $arSql);
}
/**
* Creates a sql LIMIT statement if the sparql query needs one.
* This method is needed because AdoDb does not support limits with
* prepared statements. It's a pity.
*
* @return string SQL command to be appended to a query, to limit
* the number of result rows returned.
*/
public static function getLimitSql(Query $query, ADOConnection $dbConn)
{
$arSM = $query->getSolutionModifier();
if ($arSM['limit'] === null && $arSM['offset'] === null) {
return '';
}
//this here is mysql syntax. if anyone has problems, write it
//dependent on $dbConn's type
if ($arSM['offset'] === null) {
return ' LIMIT ' . $arSM['limit'];
} else {
if ($arSM['limit'] === null) {
return ' LIMIT ' . $arSM['offset'] . ', 18446744073709551615';
} else {
return ' LIMIT ' . $arSM['offset'] . ', ' . $arSM['limit'];
}
}
}
/**
* Sorts the results.
*
* @param Array $vartable List containing the unsorted result vars
* @return Array List containing the sorted result vars
*/
protected function sortVars($vartable)
{
$newTable = array();
$mod = $this->query->getSolutionModifier();
// if no ORDER BY solution modifier return vartable
if ($mod['order by'] != null) {
$order = $mod['order by'];
$map = $this->buildVarmap($order, $vartable);
foreach ($map as $val) {
$newTable[] = $vartable[$val];
}
} else {
$newTable = $vartable;
}
if ($mod['offset'] != null) {
$newTable = array_slice($newTable, $mod['offset']);
}
if ($mod['limit'] != null) {
$newTable = array_slice($newTable, 0, $mod['limit']);
}
return $newTable;
}
