/**
* Return the LIMIT clause ready for inserting into a query.
*
* @param SQLSelect $query The expression object to build from
* @param array $parameters Out parameter for the resulting query parameters
* @return string The finalised limit SQL fragment
*/
public function buildLimitFragment(SQLSelect $query, array &$parameters)
{
$nl = $this->getSeparator();
// Ensure limit is given
$limit = $query->getLimit();
if (empty($limit)) {
return '';
}
// For literal values return this as the limit SQL
if (!is_array($limit)) {
return "{$nl}LIMIT {$limit}";
}
// Assert that the array version provides the 'limit' key
if (!array_key_exists('limit', $limit) || $limit['limit'] !== null && !is_numeric($limit['limit'])) {
throw new InvalidArgumentException('MySQLQueryBuilder::buildLimitSQL(): Wrong format for $limit: ' . var_export($limit, true));
}
if ($limit['limit'] === null) {
$limit['limit'] = self::MAX_ROWS;
}
// Format the array limit, given an optional start key
$clause = "{$nl}LIMIT {$limit['limit']}";
if (isset($limit['start']) && is_numeric($limit['start']) && $limit['start'] !== 0) {
$clause .= " OFFSET {$limit['start']}";
}
return $clause;
}
/**
* Sets the page length, page start and total items from a query object's
* limit, offset and unlimited count. The query MUST have a limit clause.
*
* @param SQLSelect $query
* @return $this
*/
public function setPaginationFromQuery(SQLSelect $query)
{
if ($limit = $query->getLimit()) {
$this->setPageLength($limit['limit']);
$this->setPageStart($limit['start']);
$this->setTotalItems($query->unlimitedRowCount());
}
return $this;
}
/**
* Test passing in a LIMIT with OFFSET clause string.
*/
public function testLimitSetFromClauseString()
{
$query = new SQLSelect();
$query->setSelect('*');
$query->setFrom('"SQLSelectTest_DO"');
$query->setLimit('20 OFFSET 10');
$limit = $query->getLimit();
$this->assertEquals(20, $limit['limit']);
$this->assertEquals(10, $limit['start']);
}
