File Source for LinqToZendDb.php

<?php
/**
* PHPLinq
*
* Copyright (c) 2008 - 2009 PHPLinq
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* @category PHPLinq
* @package PHPLinq
* @copyright Copyright (c) 2008 - 2009 PHPLinq (http://www.codeplex.com/PHPLinq)
* @license http://www.gnu.org/licenses/lgpl.txt LGPL
* @version 0.4.0, 2009-01-27
*/
/** PHPLinq */
require_once('PHPLinq.php');
/** PHPLinq_ILinqProvider */
require_once('PHPLinq/ILinqProvider.php');
/** PHPLinq_LinqToObjects */
require_once('PHPLinq/LinqToObjects.php');
/** PHPLinq_Expression */
require_once('PHPLinq/Expression.php');
/** PHPLinq_OrderByExpression */
require_once('PHPLinq/OrderByExpression.php');
/** PHPLinq_Initiator */
require_once('PHPLinq/Initiator.php');
/** PHPLinq_Adapter_Abstract */
require_once('PHPLinq/Adapter/Abstract.php');
/** Zend_Db_Table */
require_once('Zend/Db/Table.php');
/** Register ILinqProvider */
PHPLinq_Initiator::registerProvider('PHPLinq_LinqToZendDb');
/**
* PHPLinq_LinqToZendDb
*
* @category PHPLinq
* @package PHPLinq
* @copyright Copyright (c) 2008 - 2009 PHPLinq (http://www.codeplex.com/PHPLinq)
*/
class PHPLinq_LinqToZendDb implements PHPLinq_ILinqProvider {
/** Constants */
const T_FUNCTION = 1001001;
const T_PROPERTY = 1001002;
const T_CONSTANT = 1001003;
const T_VARIABLE = 1001004;
const T_OBJECT_OPERATOR = 1001005;
const T_OPERATOR = 1001006;
const T_OPERAND = 1001007;
const T_DEFAULT = 1001008;
const T_START_STOP = 1001009;
const T_SIMPLE = 1001010;
const T_ARGUMENT = 1001011;
const T_ARITHMETIC = 1001012;
/**
* Default variable name
*
* @var string
*/
private $_from = '';
/**
* Data source
*
* @var mixed
*/
private $_data = null;
/**
* Where expression
*
* @var PHPLinq_Expression
*/
private $_where = null;
/**
* Take n elements
*
* @var int?
*/
private $_take = null;
/**
* Skip n elements
*
* @var int?
*/
private $_skip = null;
/**
* Take while expression is true
*
* @var PHPLinq_Expression
*/
private $_takeWhile = null;
/**
* Skip while expression is true
*
* @var PHPLinq_Expression
*/
private $_skipWhile = null;
/**
* OrderBy expressions
*
* @var PHPLinq_Expression[]
*/
private $_orderBy = array();
/**
* Distinct expression
*
* @var PHPLinq_Expression
*/
private $_distinct = null;
/**
* OfType expression
*
* @var PHPLinq_Expression
*/
private $_ofType = null;
/**
* Parent PHPLinq_ILinqProvider instance, used with join conditions
*
* @var PHPLinq_ILinqProvider
*/
private $_parentProvider = null;
/**
* Child PHPLinq_ILinqProvider instances, used with join conditions
*
* @var PHPLinq_ILinqProvider[]
*/
private $_childProviders = array();
/**
* Join condition
*
* @var PHPLinq_Expression
*/
private $_joinCondition = null;
/**
* Is object destructing?
*
* @var bool
*/
private $_isDestructing;
/**
* PHPLinq_Adapter_Abstract instance
*
* @var PHPLinq_Adapter_Abstract
*/
private $_adapter = null;
/**
* Columns to select
*
* @var string
*/
private $_columns = '*';
/**
* Query callback (static for all PHPLinq_LinqToZendDb !)
*
* Function accepting a string to which query strings can be logged.
*
* @var mixed
*/
private static $_queryCallback = null;
/**
* Static list of PHP internal functions used for generating queries
*
* @var array
*/
private static $_internalFunctions = null;
/**
* Can this provider type handle data in $source?
*
* @param mixed $source
* @return bool
*/
public static function handles($source) {
return $source instanceof Zend_Db_Table;
}
/**
* Create a new class instance
*
* @param string $name
* @param PHPLinq_ILinqProvider $parentProvider Optional parent PHPLinq_ILinqProvider instance, used with join conditions
* @return PHPLinq_ILinqProvider
*/
public function __construct($name, PHPLinq_ILinqProvider $parentProvider = null) {
if (is_null(self::$_internalFunctions)) {
$internalFunctions = get_defined_functions();
$internalFunctions['internal'][] = 'print'; // Add as PHP function
self::$_internalFunctions = $internalFunctions['internal'];
}
$this->_from = $name;
if (!is_null($parentProvider)) {
$this->_parentProvider = $parentProvider;
$parentProvider->addChildProvider($this);
}
return $this;
}
/**
* Class destructor
*/
public function __destruct() {
$this->_isDestructing = true;
if (isset($this->_parentProvider) && !is_null($this->_parentProvider)) {
if (!$this->_parentProvider->__isDestructing()) {
$this->_parentProvider->__destruct();
}
$this->_parentProvider = null;
unset($this->_parentProvider);
}
if (!is_null($this->_childProviders)) {
foreach ($this->_childProviders as $provider) {
$provider->__destruct();
$provider = null;
unset($provider);
}
}
}
/**
* Is object destructing?
*
* @return bool
*/
public function __isDestructing() {
return $this->_isDestructing;
}
/**
* Get join condition
*
* @return PHPLinq_Expression
*/
public function getJoinCondition() {
return $this->_joinCondition;
}
/**
* Add child provider, used with joins
*
* @param PHPLinq_ILinqProvider $provider
*/
public function addChildProvider(PHPLinq_ILinqProvider $provider) {
$this->_childProviders[] = $provider;
}
/**
* Retrieve "from" name
*
* @return string
*/
public function getFromName() {
return $this->_from;
}
/**
* Retrieve data in data source
*
* @return mixed
*/
public function getSource() {
return $this->_data;
}
/**
* Set source of data
*
* @param mixed $source
* @return PHPLinq_ILinqProvider
*/
public function in($source) {
$this->_data = $source;
// Configure PHPLinq_Adapter_Abstract
$zendDbAdapter = get_class($source->getAdapter());
$phpLinqAdapter = str_replace('Zend_Db', 'PHPLinq', $zendDbAdapter);
require_once(str_replace('_', '/', $phpLinqAdapter) . '.php');
$this->_adapter = new $phpLinqAdapter($source->getAdapter());
return $this;
}
/**
* Select
*
* @param string $expression Expression which creates a resulting element
* @return mixed
*/
public function select($expression = null) {
// Return value
$returnValue = array();
// Zend_Db_Select expression
$zendDbSelect = null;
// Expression set?
if (is_null($expression) || $expression == '') {
$expression = $this->_from . ' => ' . $this->_from;
}
// Data source
$dataSourceInfo = $this->_data->info();
$dataSource = $this->_data->select()->from( array($this->_from => $dataSourceInfo['name']), $this->_columns );
// Create selector expression
$selector = new PHPLinq_Expression($expression, $this->_from);
// Build Zend_Db_Select chain
$zendDbSelect = $dataSource;
// Distinct set?
if (!is_null($this->_distinct)) {
$zendDbSelect = $zendDbSelect->distinct();
}
// Join set?
if (count($this->_childProviders) > 0) {
// Check if the child providers can be supported
foreach ($this->_childProviders as $provider) {
if (get_class($provider) != __CLASS__) {
throw new PHPLinq_Exception('Joins of ' . get_class($provider) . ' on ' . __CLASS__ . ' are not supported.');
} else {
// Supported! Add join
$joinInfo = $provider->getSource()->info();
$dataSource = $dataSource->join(
array($provider->getFromName() => $joinInfo['name']),
$this->_convertToSql($provider->getJoinCondition()->getFunction()->getFunctionCode())
);
}
}
}
// Where expresion set? Evaluate it!
if (!is_null($this->_where)) {
$functionCode = $this->_convertToSql(
$this->_where->getFunction()->getFunctionCode(),
$dataSource->getAdapter()->getQuoteIdentifierSymbol()
);
$zendDbSelect = $zendDbSelect->where($functionCode);
}
// OrderBy set?
if (is_array($this->_orderBy) && count($this->_orderBy) > 0) {
$orderBy = array();
foreach ($this->_orderBy as $orderByExpression) {
$orderBy[] = new Zend_Db_Expr(
$this->_convertToSql(
$orderByExpression->getExpression()->getFunction()->getFunctionCode()
) . ($orderByExpression->isDescending() ? ' DESC' : ' ASC')
);
}
$zendDbSelect = $zendDbSelect->order($orderBy);
}
// Take / skip
$zendDbSelect->limit($this->_take, $this->_skip);
// No integrity check needed, joins can be free format
$zendDbSelect->setIntegrityCheck(false);
// Log query string
if (!is_null(self::$_queryCallback)) {
if (!is_array(self::$_queryCallback) && in_array(self::$_queryCallback, self::$_internalFunctions)) {
self::$_queryCallback = create_function('$query', self::$_queryCallback . '($query);');
}
call_user_func(self::$_queryCallback, $zendDbSelect->__toString());
}
// Query
$results = null;
if (count($this->_childProviders) == 0) {
// No join, easy!
$results = $zendDbSelect->query(Zend_Db::FETCH_OBJ)->fetchAll();
// Row class set? If so, convert all data!
if ($this->_data->getRowClass() != 'Zend_Db_Table_Row') {
$rowClass = $this->_data->getRowClass();
$tempResults = array();
foreach ($results as $result) {
$tempResult = call_user_func( array($rowClass, 'fromArray'), (array)$result );
$tempResults[] = $tempResult;
}
$results = $tempResults;
}
} else {
// Get data in mode FETCH_NAMED
$tempResults = $zendDbSelect->query(Zend_Db::FETCH_NAMED)->fetchAll();
// Fetch info
$info = array( $this->_data->info() );
foreach ($this->_childProviders as $provider) {
$info[] = $provider->getSource()->info();
}
// Build proper resultset
$results = array();
$currentResult = null;
$currentObject = null;
foreach ($tempResults as $tempResult) {
$currentResult = array();
// For each table, add a new object with values
for ($i = 0; $i < count($info); $i++) {
// Fill object data
$currentObject = array();
foreach($info[$i]['cols'] as $column) {
if (!is_array($tempResult[$column])) {
// Regular column
$currentObject[$column] = $tempResult[$column];
} else {
// Some searching to do...
for ($j = $i; $j >= 0; $j--) {
if (isset($tempResult[$column][$j])) {
$currentObject[$column] = $tempResult[$column][$j];
$j = -1;
}
}
}
}
// Add object to result table.
// Row class set? If so, convert all data!
if ( ($i == 0 && $this->_data->getRowClass() != 'Zend_Db_Table_Row') ||
$this->_childProviders[$i - 1]->getSource()->getRowClass() != 'Zend_Db_Table_Row') {
$rowClass = $i == 0 ? $this->_data->getRowClass() : $this->_childProviders[$i - 1]->getSource()->getRowClass();
$currentResult[] = call_user_func( array($rowClass, 'fromArray'), (array)$currentObject );
} else {
$currentResult[] = (object)$currentObject;
}
}
$results[] = $currentResult;
}
}
// Loop trough data source
foreach ($results as $value) {
// Is it a valid element?
$isValid = true;
// OfType expresion set? Evaluate it!
if ($isValid && !is_null($this->_ofType)) {
$isValid = $this->_ofType->execute($value);
}
// The element is valid, check if it is our selection range
if ($isValid) {
// Skip element?
if (!is_null($this->_skipWhile) && $this->_skipWhile->execute($value)) {
$isValid = false;
}
// Take element?
if (!is_null($this->_takeWhile) && !$this->_takeWhile->execute($value)) {
$isValid = false;
break;
}
// Add the element to the return value if it is a valid element
if ($isValid) {
$returnValue[] = $selector->execute($value);
}
}
}
// TODO:
// - join
// - aggregates
// - translate more SQL!
// Return value
return $returnValue;
}
/**
* Converts PHP code into SQL code
*
* @param string $phpCode Code to convert
* @return string
*/
private function _convertToSql($phpCode) {
// Some fast cleaning
$phpCode = str_replace('return ', '', $phpCode);
$phpCode = str_replace(';', '', $phpCode);
// Adapter functions
$adapterFunctions = $this->_adapter->getFunctions();
// Go parse!
$tokens = token_get_all('<?php ' . $phpCode . '?>');
$stack = array();
$tokenId = 0;
$depth = 0;
for ($i = 0; $i < count($tokens); $i++) {
// Ignore token?
$ignoreToken = false;
// Token details
$previousToken = $i > 0 ? $tokens[$i - 1] : null;
$token = $tokens[$i];
$nextToken = $i < count($tokens) - 1 ? $tokens[$i + 1] : null;
// Parse token
if (is_array($token)) {
switch ($token[0]) {
case T_OPEN_TAG:
case T_CLOSE_TAG:
$ignoreToken = true;
break;
case T_STRING:
if (in_array($token[1], $adapterFunctions)) {
// It is an adapter function!
$stack[$tokenId]['token'] = '$this->_adapter->' . $token[1];
$stack[$tokenId]['type'] = self::T_FUNCTION;
} else if (in_array($token[1], self::$_internalFunctions)) {
// If it is a PHP function, let's take a lucky
// shot and expect the syntax to be the same...
$stack[$tokenId]['token'] = $token[1];
$stack[$tokenId]['type'] = self::T_FUNCTION;
} else {
// Probably some sort of constant / property name
if (!is_null($previousToken) && is_array($previousToken) && $previousToken[0] == T_OBJECT_OPERATOR) {
$stack[$tokenId]['token'] = $this->_adapter->quoteIdentifier($token[1]) . '\'';
$stack[$tokenId]['type'] = self::T_PROPERTY;
} else {
$stack[$tokenId]['token'] = '\'' . $token[1] . '\'';
$stack[$tokenId]['type'] = self::T_CONSTANT;
}
}
break;
case T_VARIABLE:
$stack[$tokenId]['token'] = $this->_adapter->quote($token[1]);
$stack[$tokenId]['type'] = self::T_VARIABLE;
break;
case T_OBJECT_OPERATOR:
if (!is_null($previousToken) && is_array($previousToken) && $previousToken[0] == T_VARIABLE) {
$stack[$tokenId - 1]['token'] = '\'' . addslashes($stack[$tokenId - 1]['token']) . '.';
$ignoreToken = true;
} else {
$stack[$tokenId]['token'] = '\'.\'';
}
$stack[$tokenId]['type'] = self::T_OBJECT_OPERATOR;
break;
case T_IS_IDENTICAL:
case T_IS_EQUAL:
$stack[$tokenId]['token'] = '\' ' . $this->_adapter->operator('=') . ' \'';
$stack[$tokenId]['type'] = self::T_OPERATOR;
break;
case T_IS_NOT_EQUAL:
case T_IS_NOT_IDENTICAL:
$stack[$tokenId]['token'] = '\' ' . $this->_adapter->operator('!=') . ' \'';
$stack[$tokenId]['type'] = self::T_OPERATOR;
break;
case T_IS_GREATER_OR_EQUAL:
$stack[$tokenId]['token'] = '\' ' . $this->_adapter->operator('>=') . ' \'';
$stack[$tokenId]['type'] = self::T_OPERATOR;
break;
case T_IS_SMALLER_OR_EQUAL:
$stack[$tokenId]['token'] = '\' ' . $this->_adapter->operator('<=') . ' \'';
$stack[$tokenId]['type'] = self::T_OPERATOR;
break;
case T_BOOLEAN_AND:
case T_LOGICAL_AND:
$stack[$tokenId]['token'] = '\' ' . $this->_adapter->operand('AND') . ' \'';
$stack[$tokenId]['type'] = self::T_OPERAND;
break;
case T_BOOLEAN_OR:
case T_LOGICAL_OR:
$stack[$tokenId]['token'] = '\' ' . $this->_adapter->operand('OR') . ' \'';
$stack[$tokenId]['type'] = self::T_OPERAND;
break;
default:
$stack[$tokenId]['token'] = '\'' . $token[1] . '\'';
$stack[$tokenId]['type'] = self::T_DEFAULT;
break;
}
} else {
// Simple token
if ($token != '(' && $token != ')') {
$stack[$tokenId]['token'] = $token;
$stack[$tokenId]['type'] = self::T_SIMPLE;
if ($token == ',') {
$stack[$tokenId]['type'] = self::T_ARGUMENT;
} else if ($token == '+' || $token == '-' || $token == '*' || $token == '/' || $token == '%' || $token == '.') {
$stack[$tokenId]['token'] = '\'' . $this->_adapter->operator($token) . '\'';
$stack[$tokenId]['type'] = self::T_ARITHMETIC;
} else if ($token == '>' || $token == '<') {
$stack[$tokenId]['token'] = '\' ' . $this->_adapter->operator($token) . ' \'';
$stack[$tokenId]['type'] = self::T_OPERATOR;
}
} else {
$stack[$tokenId]['token'] = '';
$stack[$tokenId]['type'] = self::T_START_STOP;
}
}
// Token metadata
if (!$ignoreToken) {
// Depth
if (!is_array($token) && $token == '(') $depth++;
if (!is_array($token) && $token == ')') $depth--;
$stack[$tokenId]['depth'] = $depth;
// Identifier
$tokenId++;
}
}
// Display tree
/*
foreach ($stack as $node) {
for ($i = 0; $i <= $node['depth']; $i++) {
echo "| ";
}
echo $node['type'] . ' - ' . $node['token'] . "\r\n";
}
die();
*/
// Build compilation string
$compileCode = '';
$functionDepth = array();
$depth = 0;
for ($i = 0; $i < count($stack); $i++) {
// Token details
$previousToken = $i > 0 ? $stack[$i - 1] : null;
$token = $stack[$i];
$nextToken = $i < count($stack) - 1 ? $stack[$i + 1] : null;
// Regular token
if ($token['depth'] == $depth && $token['type'] != self::T_START_STOP) {
$compileCode .= $token['token'];
}
// Start/stop
if ($token['depth'] > $depth && $token['type'] == self::T_START_STOP && !is_null($previousToken) && $previousToken['type'] == self::T_FUNCTION) {
$compileCode .= '(';
$functionDepth[$depth] = self::T_FUNCTION;
} else if ($token['depth'] < $depth && $token['type'] == self::T_START_STOP && $functionDepth[ $token['depth'] ] == self::T_FUNCTION) {
$compileCode .= ')';
} else if ($token['depth'] > $depth && $token['type'] == self::T_START_STOP) {
$compileCode .= '\'(\'';
$functionDepth[$depth] = self::T_START_STOP;
} else if ($token['depth'] < $depth && $token['type'] == self::T_START_STOP) {
$compileCode .= '\')\'';
}
// Next token needs concatenation?
if (!is_null($nextToken) && $nextToken['type'] != self::T_ARGUMENT) {
if (
!($token['type'] == self::T_FUNCTION && $nextToken['type'] == self::T_START_STOP) &&
!(!is_null($previousToken) && $previousToken['type'] == self::T_FUNCTION && $token['type'] == self::T_START_STOP) &&
!($token['type'] == self::T_ARGUMENT) &&
!(!is_null($nextToken) && $nextToken['type'] == self::T_START_STOP && isset($functionDepth[ $nextToken['depth'] ]) && $functionDepth[ $nextToken['depth'] ] == self::T_FUNCTION) &&
!($token['type'] == self::T_VARIABLE && !is_null($nextToken) && $nextToken['type'] == self::T_PROPERTY)
) {
$compileCode .= ' . ';
}
}
// Depth
if ($token['depth'] < $depth) {
unset($functionDepth[$token['depth']]);
}
$depth = $token['depth'];
}
// Compile
$compileCode = '$compileCode = ' . $compileCode . ';';
eval($compileCode);
return $compileCode;
}
/**
* Where
*
* @param string $expression Expression checking if an element should be contained
* @return PHPLinq_ILinqProvider
*/
public function where($expression) {
$this->_where = !is_null($expression) ? new PHPLinq_Expression($expression, $this->_from) : null;
return $this;
}
/**
* Take $n elements
*
* @param int $n
* @return PHPLinq_ILinqProvider
*/
public function take($n) {
$this->_take = $n;
return $this;
}
/**
* Skip $n elements
*
* @param int $n
* @return PHPLinq_ILinqProvider
*/
public function skip($n) {
$this->_skip = $n;
return $this;
}
/**
* Take elements while $expression evaluates to true
*
* @param string $expression Expression to evaluate
* @return PHPLinq_ILinqProvider
*/
public function takeWhile($expression) {
$this->_takeWhile = !is_null($expression) ? new PHPLinq_Expression($expression, $this->_from) : null;
return $this;
}
/**
* Skip elements while $expression evaluates to true
*
* @param string $expression Expression to evaluate
* @return PHPLinq_ILinqProvider
*/
public function skipWhile($expression) {
$this->_skipWhile = !is_null($expression) ? new PHPLinq_Expression($expression, $this->_from) : null;
return $this;
}
/**
* OrderBy
*
* @param string $expression Expression to order elements by
* @param string $comparer Comparer function (taking 2 arguments, returning -1, 0, 1)
* @return PHPLinq_ILinqProvider
*/
public function orderBy($expression, $comparer = null) {
$this->_orderBy[0] = new PHPLinq_OrderByExpression($expression, $this->_from, false, $comparer);
return $this;
}
/**
* OrderByDescending
*
* @param string $expression Expression to order elements by
* @param string $comparer Comparer function (taking 2 arguments, returning -1, 0, 1)
* @return PHPLinq_ILinqProvider
*/
public function orderByDescending($expression, $comparer = null) {
$this->_orderBy[0] = new PHPLinq_OrderByExpression($expression, $this->_from, true, $comparer);
return $this;
}
/**
* ThenBy
*
* @param string $expression Expression to order elements by
* @param string $comparer Comparer function (taking 2 arguments, returning -1, 0, 1)
* @return PHPLinq_ILinqProvider
*/
public function thenBy($expression, $comparer = null) {
$this->_orderBy[] = new PHPLinq_OrderByExpression($expression, $this->_from, false, $comparer);
return $this;
}
/**
* ThenByDescending
*
* @param string $expression Expression to order elements by
* @param string $comparer Comparer function (taking 2 arguments, returning -1, 0, 1)
* @return PHPLinq_ILinqProvider
*/
public function thenByDescending($expression, $comparer = null) {
$this->_orderBy[] = new PHPLinq_OrderByExpression($expression, $this->_from, true, $comparer);
return $this;
}
/**
* Distinct
*
* @param string $expression Ignored.
* @return PHPLinq_ILinqProvider
*/
public function distinct($expression) {
$this->_distinct = !is_null($expression) ? new PHPLinq_Expression($expression, $this->_from) : null;
return $this;
}
/**
* Select the elements of a certain type
*
* @param string $type Type name
*/
public function ofType($type) {
// Create a new expression
$expression = $this->_from . ' => ';
// Evaluate type
switch (strtolower($type)) {
case 'array':
case 'bool':
case 'double':
case 'float':
case 'int':
case 'integer':
case 'long':
case 'null':
case 'numeric':
case 'object':
case 'real':
case 'scalar':
case 'string':
$expression .= 'is_' . strtolower($type) . '(' . $this->_from . ')';
break;
default:
$expression .= 'is_a(' . $this->_from . ', "' . $type . '")';
break;
}
// Assign expression
$this->_ofType = new PHPLinq_Expression($expression, $this->_from);
return $this;
}
/**
* Any
*
* @param string $expression Expression checking if an element is contained
* @return boolean
*/
public function any($expression) {
$originalWhere = $this->_where;
$this->_columns = 'COUNT(*) AS cnt';
$countFrom = $this->_from . ' => ' . $this->_from . '->cnt';
$result = $this->where($expression)->select($countFrom);
$this->_columns = '*';
$this->_where = $originalWhere;
return $result[0] > 0;
}
/**
* All
*
* @param string $expression Expression checking if an all elements are contained
* @return boolean
*/
public function all($expression) {
$originalWhere = $this->_where;
$this->_columns = 'COUNT(*) AS cnt';
$countFrom = $this->_from . ' => ' . $this->_from . '->cnt';
$result1 = $this->where($expression)->select($countFrom);
$result2 = $this->where(null)->select($countFrom);
$this->_columns = '*';
$this->_where = $originalWhere;
return $result1[0] == $result2[0];
}
/**
* Contains - Not performed as query! (heavy)
*
* @param mixed $element Is the $element contained?
* @return boolean
*/
public function contains($element) {
return in_array($element, $this->select());
}
/**
* Reverse elements - Not performed as query! (heavy)
*
* @param bool $preserveKeys Preserve keys?
* @return PHPLinq_ILinqProvider
*/
public function reverse($preserveKeys = null) {
$data = array_reverse($this->select(), $preserveKeys);
return linqfrom($this->_from)->in($data);
}
/**
* Element at index
*
* @param mixed $index Index
* @return mixed Element at $index
*/
public function elementAt($index = null) {
$originalWhere = $this->_where;
$result = $this->where(null)->take(1)->skip($index)->select();
$this->_where = $originalWhere;
if (count($result) > 0) {
return array_shift($result);
}
return null;
}
/**
* Element at index or default
*
* @param mixed $index Index
* @param mixed $defaultValue Default value to return if nothing is found
* @return mixed Element at $index
*/
public function elementAtOrDefault($index = null, $defaultValue = null) {
$returnValue = $this->elementAt($index);
if (!is_null($returnValue)) {
return $returnValue;
} else {
return $defaultValue;
}
}
/**
* Concatenate data
*
* @param mixed $source
* @return PHPLinq_ILinqProvider
*/
public function concat($source) {
$data = array_merge($this->select(), $source);
return linqfrom($this->_from)->in($data);
}
/**
* First
*
* @param string $expression Expression which creates a resulting element
* @return mixed
*/
public function first($expression = null) {
$linqCommand = clone $this;
$result = $linqCommand->skip(0)->take(1)->select($expression);
if (count($result) > 0) {
return array_shift($result);
}
return null;
}
/**
* FirstOrDefault
*
* @param string $expression Expression which creates a resulting element
* @param mixed $defaultValue Default value to return if nothing is found
* @return mixed
*/
public function firstOrDefault ($expression = null, $defaultValue = null) {
$returnValue = $this->first($expression);
if (!is_null($returnValue)) {
return $returnValue;
} else {
return $defaultValue;
}
}
/**
* Last
*
* @param string $expression Expression which creates a resulting element
* @return mixed
*/
public function last($expression = null) {
$linqCommand = clone $this;
$result = $linqCommand->reverse()->skip(0)->take(1)->select($expression);
if (count($result) > 0) {
return array_shift($result);
}
return null;
}
/**
* LastOrDefault
*
* @param string $expression Expression which creates a resulting element
* @param mixed $defaultValue Default value to return if nothing is found
* @return mixed
*/
public function lastOrDefault ($expression = null, $defaultValue = null) {
$returnValue = $this->last($expression);
if (!is_null($returnValue)) {
return $returnValue;
} else {
return $defaultValue;
}
}
/**
* Single
*
* @param string $expression Expression which creates a resulting element
* @return mixed
*/
public function single($expression = null) {
return $this->first($expression);
}
/**
* SingleOrDefault
*
* @param string $expression Expression which creates a resulting element
* @param mixed $defaultValue Default value to return if nothing is found
* @return mixed
*/
public function singleOrDefault ($expression = null, $defaultValue = null) {
return $this->firstOrDefault($expression, $defaultValue);
}
/**
* Join
*
* @param string $name
* @return PHPLinq_Initiator
*/
public function join($name) {
return new PHPLinq_Initiator($name, $this);
}
/**
* On
*
* @param string $expression Expression representing join condition
* @return PHPLinq_ILinqProvider
*/
public function on($expression) {
$this->_joinCondition = new PHPLinq_Expression($expression, $this->_from);
return $this->_parentProvider;
}
/**
* Count elements
*
* @return int Element count
*/
public function count() {
return count($this->_data);
}
/**
* Sum elements
*
* @return mixed Sum of elements
*/
public function sum() {
return array_sum($this->_data); // $this->aggregate(0, '$s, $t => $s + $t');
}
/**
* Minimum of elements
*
* @return mixed Minimum of elements
*/
public function min(){
return min($this->_data);
}
/**
* Maximum of elements
*
* @return mixed Maximum of elements
*/
public function max(){
return max($this->_data);
}
/**
* Average of elements
*
* @return mixed Average of elements
*/
public function average(){
return $this->sum() / $this->count();
}
/**
* Aggregate
*
* Example: Equivalent of count(): $this->aggregate(0, '$s, $t => $s + 1');
*
* @param int $seed Seed
* @param string $expression Expression defining the aggregate
* @return mixed aggregate
*/
public function aggregate($seed = 0, $expression) {
$codeExpression = new PHPLinq_Expression($expression);
$runningValue = $seed;
foreach ($this->_data as $value) {
$runningValue = $codeExpression->execute( array($runningValue, $value) );
}
return $runningValue;
}
/**
* Get query callback (static for all PHPLinq_LinqToZendDb !)
*
* Function accepting a string to which query strings can be logged.
*
* @return mixed
*/
public static function getQueryCallback() {
return self::$_queryCallback;
}
/**
* Set query callback (static for all PHPLinq_LinqToZendDb !)
*
* Function accepting a string to which query strings can be logged.
*
* @param mixed $value
*/
public static function setQueryCallback($value = null) {
self::$_queryCallback = $value;
}
}

Source for file LinqToZendDb.php