<?php
/**
* @package FrameworkOnFramework
* @subpackage database
* @copyright Copyright (C) 2010-2016 Nicholas K. Dionysopoulos / Akeeba Ltd. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*
* This file is adapted from the Joomla! Platform. It is used to iterate a database cursor returning FOFTable objects
* instead of plain stdClass objects
*/
// Protect from unauthorized access
defined('FOF_INCLUDED') or die;
/**
* Query Building Class.
*
* @since 11.1
*/
class FOFDatabaseQuerySqlsrv extends FOFDatabaseQuery implements FOFDatabaseQueryLimitable
{
/**
* The character(s) used to quote SQL statement names such as table names or field names,
* etc. The child classes should define this as necessary. If a single character string the
* same character is used for both sides of the quoted name, else the first character will be
* used for the opening quote and the second for the closing quote.
*
* @var string
* @since 11.1
*/
protected $name_quotes = '`';
/**
* The null or zero representation of a timestamp for the database driver. This should be
* defined in child classes to hold the appropriate value for the engine.
*
* @var string
* @since 11.1
*/
protected $null_date = '1900-01-01 00:00:00';
/**
* @var integer The affected row limit for the current SQL statement.
* @since 3.2
*/
protected $limit = 0;
/**
* @var integer The affected row offset to apply for the current SQL statement.
* @since 3.2
*/
protected $offset = 0;
/**
* Magic function to convert the query to a string.
*
* @return string The completed query.
*
* @since 11.1
*/
public function __toString()
{
$query = '';
switch ($this->type)
{
case 'select':
$query .= (string) $this->select;
$query .= (string) $this->from;
if ($this->join)
{
// Special case for joins
foreach ($this->join as $join)
{
$query .= (string) $join;
}
}
if ($this->where)
{
$query .= (string) $this->where;
}
if ($this->group)
{
$query .= (string) $this->group;
}
if ($this->order)
{
$query .= (string) $this->order;
}
if ($this->having)
{
$query .= (string) $this->having;
}
if ($this instanceof FOFDatabaseQueryLimitable && ($this->limit > 0 || $this->offset > 0))
{
$query = $this->processLimit($query, $this->limit, $this->offset);
}
break;
case 'insert':
$query .= (string) $this->insert;
// Set method
if ($this->set)
{
$query .= (string) $this->set;
}
// Columns-Values method
elseif ($this->values)
{
if ($this->columns)
{
$query .= (string) $this->columns;
}
$elements = $this->insert->getElements();
$tableName = array_shift($elements);
$query .= 'VALUES ';
$query .= (string) $this->values;
if ($this->autoIncrementField)
{
$query = 'SET IDENTITY_INSERT ' . $tableName . ' ON;' . $query . 'SET IDENTITY_INSERT ' . $tableName . ' OFF;';
}
if ($this->where)
{
$query .= (string) $this->where;
}
}
break;
case 'delete':
$query .= (string) $this->delete;
$query .= (string) $this->from;
if ($this->join)
{
// Special case for joins
foreach ($this->join as $join)
{
$query .= (string) $join;
}
}
if ($this->where)
{
$query .= (string) $this->where;
}
if ($this->order)
{
$query .= (string) $this->order;
}
break;
case 'update':
$query .= (string) $this->update;
if ($this->join)
{
// Special case for joins
foreach ($this->join as $join)
{
$query .= (string) $join;
}
}
$query .= (string) $this->set;
if ($this->where)
{
$query .= (string) $this->where;
}
if ($this->order)
{
$query .= (string) $this->order;
}
break;
default:
$query = parent::__toString();
break;
}
return $query;
}
/**
* Casts a value to a char.
*
* Ensure that the value is properly quoted before passing to the method.
*
* @param string $value The value to cast as a char.
*
* @return string Returns the cast value.
*
* @since 11.1
*/
public function castAsChar($value)
{
return 'CAST(' . $value . ' as NVARCHAR(10))';
}
/**
* Gets the function to determine the length of a character string.
*
* @param string $field A value.
* @param string $operator Comparison operator between charLength integer value and $condition
* @param string $condition Integer value to compare charLength with.
*
* @return string The required char length call.
*
* @since 11.1
*/
public function charLength($field, $operator = null, $condition = null)
{
return 'DATALENGTH(' . $field . ')' . (isset($operator) && isset($condition) ? ' ' . $operator . ' ' . $condition : '');
}
/**
* Concatenates an array of column names or values.
*
* @param array $values An array of values to concatenate.
* @param string $separator As separator to place between each value.
*
* @return string The concatenated values.
*
* @since 11.1
*/
public function concatenate($values, $separator = null)
{
if ($separator)
{
return '(' . implode('+' . $this->quote($separator) . '+', $values) . ')';
}
else
{
return '(' . implode('+', $values) . ')';
}
}
/**
* Gets the current date and time.
*
* @return string
*
* @since 11.1
*/
public function currentTimestamp()
{
return 'GETDATE()';
}
/**
* Get the length of a string in bytes.
*
* @param string $value The string to measure.
*
* @return integer
*
* @since 11.1
*/
public function length($value)
{
return 'LEN(' . $value . ')';
}
/**
* Add to the current date and time.
* Usage:
* $query->select($query->dateAdd());
* Prefixing the interval with a - (negative sign) will cause subtraction to be used.
*
* @param datetime $date The date to add to; type may be time or datetime.
* @param string $interval The string representation of the appropriate number of units
* @param string $datePart The part of the date to perform the addition on
*
* @return string The string with the appropriate sql for addition of dates
*
* @since 13.1
* @note Not all drivers support all units.
* @link http://msdn.microsoft.com/en-us/library/ms186819.aspx for more information
*/
public function dateAdd($date, $interval, $datePart)
{
return "DATEADD('" . $datePart . "', '" . $interval . "', '" . $date . "'" . ')';
}
/**
* Method to modify a query already in string format with the needed
* additions to make the query limited to a particular number of
* results, or start at a particular offset.
*
* @param string $query The query in string format
* @param integer $limit The limit for the result set
* @param integer $offset The offset for the result set
*
* @return string
*
* @since 12.1
*/
public function processLimit($query, $limit, $offset = 0)
{
if ($limit == 0 && $offset == 0)
{
return $query;
}
$start = $offset + 1;
$end = $offset + $limit;
$orderBy = stristr($query, 'ORDER BY');
if (is_null($orderBy) || empty($orderBy))
{
$orderBy = 'ORDER BY (select 0)';
}
$query = str_ireplace($orderBy, '', $query);
$rowNumberText = ', ROW_NUMBER() OVER (' . $orderBy . ') AS RowNumber FROM ';
$query = preg_replace('/\sFROM\s/i', $rowNumberText, $query, 1);
$query = 'SELECT * FROM (' . $query . ') A WHERE A.RowNumber BETWEEN ' . $start . ' AND ' . $end;
return $query;
}
/**
* Sets the offset and limit for the result set, if the database driver supports it.
*
* Usage:
* $query->setLimit(100, 0); (retrieve 100 rows, starting at first record)
* $query->setLimit(50, 50); (retrieve 50 rows, starting at 50th record)
*
* @param integer $limit The limit for the result set
* @param integer $offset The offset for the result set
*
* @return FOFDatabaseQuery Returns this object to allow chaining.
*
* @since 12.1
*/
public function setLimit($limit = 0, $offset = 0)
{
$this->limit = (int) $limit;
$this->offset = (int) $offset;
return $this;
}
/**
* Return correct rand() function for MSSQL.
*
* Ensure that the rand() function is MSSQL compatible.
*
* Usage:
* $query->Rand();
*
* @return string The correct rand function.
*
* @since 3.5
*/
public function Rand()
{
return ' NEWID() ';
}
}