File indexing completed on 2025-01-19 05:21:03

 <?php
 /**
  * Zend Framework
  *
  * LICENSE
  *
  * This source file is subject to the new BSD license that is bundled
  * with this package in the file LICENSE.txt.
  * It is also available through the world-wide-web at this URL:
  * http://framework.zend.com/license/new-bsd
  * If you did not receive a copy of the license and are unable to
  * obtain it through the world-wide-web, please send an email
  * to license@zend.com so we can send you a copy immediately.
  *
  * @category   Zend
  * @package    Zend_Db
  * @subpackage Select
  * @copyright  Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
  * @license    http://framework.zend.com/license/new-bsd     New BSD License
  * @version    $Id$
  */
 
 
 /**
  * @see Zend_Db_Adapter_Abstract
  */
 // require_once 'Zend/Db/Adapter/Abstract.php';
 
 /**
  * @see Zend_Db_Expr
  */
 // require_once 'Zend/Db/Expr.php';
 
 
 /**
  * Class for SQL SELECT generation and results.
  *
  * @category   Zend
  * @package    Zend_Db
  * @subpackage Select
  * @copyright  Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
  * @license    http://framework.zend.com/license/new-bsd     New BSD License
  */
 class Zend_Db_Select
 {
 
     const DISTINCT       = 'distinct';
     const COLUMNS        = 'columns';
     const FROM           = 'from';
     const UNION          = 'union';
     const WHERE          = 'where';
     const GROUP          = 'group';
     const HAVING         = 'having';
     const ORDER          = 'order';
     const LIMIT_COUNT    = 'limitcount';
     const LIMIT_OFFSET   = 'limitoffset';
     const FOR_UPDATE     = 'forupdate';
 
     const INNER_JOIN     = 'inner join';
     const LEFT_JOIN      = 'left join';
     const RIGHT_JOIN     = 'right join';
     const FULL_JOIN      = 'full join';
     const CROSS_JOIN     = 'cross join';
     const NATURAL_JOIN   = 'natural join';
 
     const SQL_WILDCARD   = '*';
     const SQL_SELECT     = 'SELECT';
     const SQL_UNION      = 'UNION';
     const SQL_UNION_ALL  = 'UNION ALL';
     const SQL_FROM       = 'FROM';
     const SQL_WHERE      = 'WHERE';
     const SQL_DISTINCT   = 'DISTINCT';
     const SQL_GROUP_BY   = 'GROUP BY';
     const SQL_ORDER_BY   = 'ORDER BY';
     const SQL_HAVING     = 'HAVING';
     const SQL_FOR_UPDATE = 'FOR UPDATE';
     const SQL_AND        = 'AND';
     const SQL_AS         = 'AS';
     const SQL_OR         = 'OR';
     const SQL_ON         = 'ON';
     const SQL_ASC        = 'ASC';
     const SQL_DESC       = 'DESC';
 
     const REGEX_COLUMN_EXPR       = '/^([\w]*\s*\(([^\(\)]|(?1))*\))$/';
     const REGEX_COLUMN_EXPR_ORDER = '/^([\w]+\s*\(([^\(\)]|(?1))*\))$/';
     const REGEX_COLUMN_EXPR_GROUP = '/^([\w]+\s*\(([^\(\)]|(?1))*\))$/';
     
     // @see http://stackoverflow.com/a/13823184/2028814
     const REGEX_SQL_COMMENTS      = '@
     (([\'"]).*?[^\\\]\2) # $1 : Skip single & double quoted expressions
     |(                   # $3 : Match comments
         (?:\#|--).*?$    # - Single line comments
         |                # - Multi line (nested) comments
          /\*             #   . comment open marker
             (?: [^/*]    #   . non comment-marker characters
                 |/(?!\*) #   . ! not a comment open
                 |\*(?!/) #   . ! not a comment close
                 |(?R)    #   . recursive case
             )*           #   . repeat eventually
         \*\/             #   . comment close marker
     )\s*                 # Trim after comments
     |(?<=;)\s+           # Trim after semi-colon
     @msx';
 
     /**
      * Bind variables for query
      *
      * @var array
      */
     protected $_bind = array();
 
     /**
      * Zend_Db_Adapter_Abstract object.
      *
      * @var Zend_Db_Adapter_Abstract
      */
     protected $_adapter;
 
     /**
      * The initial values for the $_parts array.
      * NOTE: It is important for the 'FOR_UPDATE' part to be last to ensure
      * meximum compatibility with database adapters.
      *
      * @var array
      */
     protected static $_partsInit = array(
         self::DISTINCT     => false,
         self::COLUMNS      => array(),
         self::UNION        => array(),
         self::FROM         => array(),
         self::WHERE        => array(),
         self::GROUP        => array(),
         self::HAVING       => array(),
         self::ORDER        => array(),
         self::LIMIT_COUNT  => null,
         self::LIMIT_OFFSET => null,
         self::FOR_UPDATE   => false
     );
 
     /**
      * Specify legal join types.
      *
      * @var array
      */
     protected static $_joinTypes = array(
         self::INNER_JOIN,
         self::LEFT_JOIN,
         self::RIGHT_JOIN,
         self::FULL_JOIN,
         self::CROSS_JOIN,
         self::NATURAL_JOIN,
     );
 
     /**
      * Specify legal union types.
      *
      * @var array
      */
     protected static $_unionTypes = array(
         self::SQL_UNION,
         self::SQL_UNION_ALL
     );
 
     /**
      * The component parts of a SELECT statement.
      * Initialized to the $_partsInit array in the constructor.
      *
      * @var array
      */
     protected $_parts = array();
 
     /**
      * Tracks which columns are being select from each table and join.
      *
      * @var array
      */
     protected $_tableCols = array();
 
     /**
      * Class constructor
      *
      * @param Zend_Db_Adapter_Abstract $adapter
      */
     public function __construct(Zend_Db_Adapter_Abstract $adapter)
     {
         $this->_adapter = $adapter;
         $this->_parts = self::$_partsInit;
     }
 
     /**
      * Get bind variables
      *
      * @return array
      */
     public function getBind()
     {
         return $this->_bind;
     }
 
     /**
      * Set bind variables
      *
      * @param mixed $bind
      * @return Zend_Db_Select
      */
     public function bind($bind)
     {
         $this->_bind = $bind;
 
         return $this;
     }
 
     /**
      * Makes the query SELECT DISTINCT.
      *
      * @param bool $flag Whether or not the SELECT is DISTINCT (default true).
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function distinct($flag = true)
     {
         $this->_parts[self::DISTINCT] = (bool) $flag;
         return $this;
     }
 
     /**
      * Adds a FROM table and optional columns to the query.
      *
      * The first parameter $name can be a simple string, in which case the
      * correlation name is generated automatically.  If you want to specify
      * the correlation name, the first parameter must be an associative
      * array in which the key is the correlation name, and the value is
      * the physical table name.  For example, array('alias' => 'table').
      * The correlation name is prepended to all columns fetched for this
      * table.
      *
      * The second parameter can be a single string or Zend_Db_Expr object,
      * or else an array of strings or Zend_Db_Expr objects.
      *
      * The first parameter can be null or an empty string, in which case
      * no correlation name is generated or prepended to the columns named
      * in the second parameter.
      *
      * @param  array|string|Zend_Db_Expr $name The table name or an associative array
      *                                         relating correlation name to table name.
      * @param  array|string|Zend_Db_Expr $cols The columns to select from this table.
      * @param  string $schema The schema name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function from($name, $cols = '*', $schema = null)
     {
         return $this->_join(self::FROM, $name, null, $cols, $schema);
     }
 
     /**
      * Specifies the columns used in the FROM clause.
      *
      * The parameter can be a single string or Zend_Db_Expr object,
      * or else an array of strings or Zend_Db_Expr objects.
      *
      * @param  array|string|Zend_Db_Expr $cols The columns to select from this table.
      * @param  string $correlationName Correlation name of target table. OPTIONAL
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function columns($cols = '*', $correlationName = null)
     {
         if ($correlationName === null && count($this->_parts[self::FROM])) {
             $correlationNameKeys = array_keys($this->_parts[self::FROM]);
             $correlationName = current($correlationNameKeys);
         }
 
         if (!array_key_exists($correlationName, $this->_parts[self::FROM])) {
             /**
              * @see Zend_Db_Select_Exception
              */
             // require_once 'Zend/Db/Select/Exception.php';
             throw new Zend_Db_Select_Exception("No table has been specified for the FROM clause");
         }
 
         $this->_tableCols($correlationName, $cols);
 
         return $this;
     }
 
     /**
      * Adds a UNION clause to the query.
      *
      * The first parameter has to be an array of Zend_Db_Select or
      * sql query strings.
      *
      * <code>
      * $sql1 = $db->select();
      * $sql2 = "SELECT ...";
      * $select = $db->select()
      *      ->union(array($sql1, $sql2))
      *      ->order("id");
      * </code>
      *
      * @param  array $select Array of select clauses for the union.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function union($select = array(), $type = self::SQL_UNION)
     {
         if (!is_array($select)) {
             // require_once 'Zend/Db/Select/Exception.php';
             throw new Zend_Db_Select_Exception(
                 "union() only accepts an array of Zend_Db_Select instances of sql query strings."
             );
         }
 
         if (!in_array($type, self::$_unionTypes)) {
             // require_once 'Zend/Db/Select/Exception.php';
             throw new Zend_Db_Select_Exception("Invalid union type '{$type}'");
         }
 
         foreach ($select as $target) {
             $this->_parts[self::UNION][] = array($target, $type);
         }
 
         return $this;
     }
 
     /**
      * Adds a JOIN table and columns to the query.
      *
      * The $name and $cols parameters follow the same logic
      * as described in the from() method.
      *
      * @param  array|string|Zend_Db_Expr $name The table name.
      * @param  string $cond Join on this condition.
      * @param  array|string $cols The columns to select from the joined table.
      * @param  string $schema The database name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function join($name, $cond, $cols = self::SQL_WILDCARD, $schema = null)
     {
         return $this->joinInner($name, $cond, $cols, $schema);
     }
 
     /**
      * Add an INNER JOIN table and colums to the query
      * Rows in both tables are matched according to the expression
      * in the $cond argument.  The result set is comprised
      * of all cases where rows from the left table match
      * rows from the right table.
      *
      * The $name and $cols parameters follow the same logic
      * as described in the from() method.
      *
      * @param  array|string|Zend_Db_Expr $name The table name.
      * @param  string $cond Join on this condition.
      * @param  array|string $cols The columns to select from the joined table.
      * @param  string $schema The database name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function joinInner($name, $cond, $cols = self::SQL_WILDCARD, $schema = null)
     {
         return $this->_join(self::INNER_JOIN, $name, $cond, $cols, $schema);
     }
 
     /**
      * Add a LEFT OUTER JOIN table and colums to the query
      * All rows from the left operand table are included,
      * matching rows from the right operand table included,
      * and the columns from the right operand table are filled
      * with NULLs if no row exists matching the left table.
      *
      * The $name and $cols parameters follow the same logic
      * as described in the from() method.
      *
      * @param  array|string|Zend_Db_Expr $name The table name.
      * @param  string $cond Join on this condition.
      * @param  array|string $cols The columns to select from the joined table.
      * @param  string $schema The database name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function joinLeft($name, $cond, $cols = self::SQL_WILDCARD, $schema = null)
     {
         return $this->_join(self::LEFT_JOIN, $name, $cond, $cols, $schema);
     }
 
     /**
      * Add a RIGHT OUTER JOIN table and colums to the query.
      * Right outer join is the complement of left outer join.
      * All rows from the right operand table are included,
      * matching rows from the left operand table included,
      * and the columns from the left operand table are filled
      * with NULLs if no row exists matching the right table.
      *
      * The $name and $cols parameters follow the same logic
      * as described in the from() method.
      *
      * @param  array|string|Zend_Db_Expr $name The table name.
      * @param  string $cond Join on this condition.
      * @param  array|string $cols The columns to select from the joined table.
      * @param  string $schema The database name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function joinRight($name, $cond, $cols = self::SQL_WILDCARD, $schema = null)
     {
         return $this->_join(self::RIGHT_JOIN, $name, $cond, $cols, $schema);
     }
 
     /**
      * Add a FULL OUTER JOIN table and colums to the query.
      * A full outer join is like combining a left outer join
      * and a right outer join.  All rows from both tables are
      * included, paired with each other on the same row of the
      * result set if they satisfy the join condition, and otherwise
      * paired with NULLs in place of columns from the other table.
      *
      * The $name and $cols parameters follow the same logic
      * as described in the from() method.
      *
      * @param  array|string|Zend_Db_Expr $name The table name.
      * @param  string $cond Join on this condition.
      * @param  array|string $cols The columns to select from the joined table.
      * @param  string $schema The database name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function joinFull($name, $cond, $cols = self::SQL_WILDCARD, $schema = null)
     {
         return $this->_join(self::FULL_JOIN, $name, $cond, $cols, $schema);
     }
 
     /**
      * Add a CROSS JOIN table and colums to the query.
      * A cross join is a cartesian product; there is no join condition.
      *
      * The $name and $cols parameters follow the same logic
      * as described in the from() method.
      *
      * @param  array|string|Zend_Db_Expr $name The table name.
      * @param  array|string $cols The columns to select from the joined table.
      * @param  string $schema The database name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function joinCross($name, $cols = self::SQL_WILDCARD, $schema = null)
     {
         return $this->_join(self::CROSS_JOIN, $name, null, $cols, $schema);
     }
 
     /**
      * Add a NATURAL JOIN table and colums to the query.
      * A natural join assumes an equi-join across any column(s)
      * that appear with the same name in both tables.
      * Only natural inner joins are supported by this API,
      * even though SQL permits natural outer joins as well.
      *
      * The $name and $cols parameters follow the same logic
      * as described in the from() method.
      *
      * @param  array|string|Zend_Db_Expr $name The table name.
      * @param  array|string $cols The columns to select from the joined table.
      * @param  string $schema The database name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function joinNatural($name, $cols = self::SQL_WILDCARD, $schema = null)
     {
         return $this->_join(self::NATURAL_JOIN, $name, null, $cols, $schema);
     }
 
     /**
      * Adds a WHERE condition to the query by AND.
      *
      * If a value is passed as the second param, it will be quoted
      * and replaced into the condition wherever a question-mark
      * appears. Array values are quoted and comma-separated.
      *
      * <code>
      * // simplest but non-secure
      * $select->where("id = $id");
      *
      * // secure (ID is quoted but matched anyway)
      * $select->where('id = ?', $id);
      *
      * // alternatively, with named binding
      * $select->where('id = :id');
      * </code>
      *
      * Note that it is more correct to use named bindings in your
      * queries for values other than strings. When you use named
      * bindings, don't forget to pass the values when actually
      * making a query:
      *
      * <code>
      * $db->fetchAll($select, array('id' => 5));
      * </code>
      *
      * @param string   $cond  The WHERE condition.
      * @param mixed    $value OPTIONAL The value to quote into the condition.
      * @param int      $type  OPTIONAL The type of the given value
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function where($cond, $value = null, $type = null)
     {
         $this->_parts[self::WHERE][] = $this->_where($cond, $value, $type, true);
 
         return $this;
     }
 
     /**
      * Adds a WHERE condition to the query by OR.
      *
      * Otherwise identical to where().
      *
      * @param string   $cond  The WHERE condition.
      * @param mixed    $value OPTIONAL The value to quote into the condition.
      * @param int      $type  OPTIONAL The type of the given value
      * @return Zend_Db_Select This Zend_Db_Select object.
      *
      * @see where()
      */
     public function orWhere($cond, $value = null, $type = null)
     {
         $this->_parts[self::WHERE][] = $this->_where($cond, $value, $type, false);
 
         return $this;
     }
 
     /**
      * Adds grouping to the query.
      *
      * @param  array|string $spec The column(s) to group by.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function group($spec)
     {
         if (!is_array($spec)) {
             $spec = array($spec);
         }
 
         foreach ($spec as $val) {
             // Remove comments from SQL statement
             $noComments = preg_replace(self::REGEX_SQL_COMMENTS, '$1', (string) $val);
             if (preg_match(self::REGEX_COLUMN_EXPR_GROUP, $noComments)) {
                 $val = new Zend_Db_Expr($val);
             }
             $this->_parts[self::GROUP][] = $val;
         }
 
         return $this;
     }
 
     /**
      * Adds a HAVING condition to the query by AND.
      *
      * If a value is passed as the second param, it will be quoted
      * and replaced into the condition wherever a question-mark
      * appears. See {@link where()} for an example
      *
      * @param string $cond The HAVING condition.
      * @param mixed    $value OPTIONAL The value to quote into the condition.
      * @param int      $type  OPTIONAL The type of the given value
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function having($cond, $value = null, $type = null)
     {
         if ($value !== null) {
             $cond = $this->_adapter->quoteInto($cond, $value, $type);
         }
 
         if ($this->_parts[self::HAVING]) {
             $this->_parts[self::HAVING][] = self::SQL_AND . " ($cond)";
         } else {
             $this->_parts[self::HAVING][] = "($cond)";
         }
 
         return $this;
     }
 
     /**
      * Adds a HAVING condition to the query by OR.
      *
      * Otherwise identical to orHaving().
      *
      * @param string $cond The HAVING condition.
      * @param mixed    $value OPTIONAL The value to quote into the condition.
      * @param int      $type  OPTIONAL The type of the given value
      * @return Zend_Db_Select This Zend_Db_Select object.
      *
      * @see having()
      */
     public function orHaving($cond, $value = null, $type = null)
     {
         if ($value !== null) {
             $cond = $this->_adapter->quoteInto($cond, $value, $type);
         }
 
         if ($this->_parts[self::HAVING]) {
             $this->_parts[self::HAVING][] = self::SQL_OR . " ($cond)";
         } else {
             $this->_parts[self::HAVING][] = "($cond)";
         }
 
         return $this;
     }
 
     /**
      * Adds a row order to the query.
      *
      * @param mixed $spec The column(s) and direction to order by.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function order($spec)
     {
         if (!is_array($spec)) {
             $spec = array($spec);
         }
 
         // force 'ASC' or 'DESC' on each order spec, default is ASC.
         foreach ($spec as $val) {
             if ($val instanceof Zend_Db_Expr) {
                 $expr = $val->__toString();
                 if (empty($expr)) {
                     continue;
                 }
                 $this->_parts[self::ORDER][] = $val;
             } else {
                 if (empty($val)) {
                     continue;
                 }
                 $direction = self::SQL_ASC;
                 if (preg_match('/(.*\W)(' . self::SQL_ASC . '|' . self::SQL_DESC . ')\b/si', $val, $matches)) {
                     $val = trim($matches[1]);
                     $direction = $matches[2];
                 }
                 // Remove comments from SQL statement
                 $noComments = preg_replace(self::REGEX_SQL_COMMENTS, '$1', (string) $val);
                 if (preg_match(self::REGEX_COLUMN_EXPR_ORDER, $noComments)) {
                     $val = new Zend_Db_Expr($val);
                 }
                 $this->_parts[self::ORDER][] = array($val, $direction);
             }
         }
 
         return $this;
     }
 
     /**
      * Sets a limit count and offset to the query.
      *
      * @param int $count OPTIONAL The number of rows to return.
      * @param int $offset OPTIONAL Start returning after this many rows.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function limit($count = null, $offset = null)
     {
         $this->_parts[self::LIMIT_COUNT]  = (int) $count;
         $this->_parts[self::LIMIT_OFFSET] = (int) $offset;
         return $this;
     }
 
     /**
      * Sets the limit and count by page number.
      *
      * @param int $page Limit results to this page number.
      * @param int $rowCount Use this many rows per page.
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function limitPage($page, $rowCount)
     {
         $page     = ($page > 0)     ? $page     : 1;
         $rowCount = ($rowCount > 0) ? $rowCount : 1;
         $this->_parts[self::LIMIT_COUNT]  = (int) $rowCount;
         $this->_parts[self::LIMIT_OFFSET] = (int) $rowCount * ($page - 1);
         return $this;
     }
 
     /**
      * Makes the query SELECT FOR UPDATE.
      *
      * @param bool $flag Whether or not the SELECT is FOR UPDATE (default true).
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function forUpdate($flag = true)
     {
         $this->_parts[self::FOR_UPDATE] = (bool) $flag;
         return $this;
     }
 
     /**
      * Get part of the structured information for the current query.
      *
      * @param string $part
      * @return mixed
      * @throws Zend_Db_Select_Exception
      */
     public function getPart($part)
     {
         $part = strtolower($part);
         if (!array_key_exists($part, $this->_parts)) {
             // require_once 'Zend/Db/Select/Exception.php';
             throw new Zend_Db_Select_Exception("Invalid Select part '$part'");
         }
         return $this->_parts[$part];
     }
 
     /**
      * Executes the current select object and returns the result
      *
      * @param integer $fetchMode OPTIONAL
      * @param  mixed  $bind An array of data to bind to the placeholders.
      * @return PDO_Statement|Zend_Db_Statement
      */
     public function query($fetchMode = null, $bind = array())
     {
         if (!empty($bind)) {
             $this->bind($bind);
         }
 
         $stmt = $this->_adapter->query($this);
         if ($fetchMode == null) {
             $fetchMode = $this->_adapter->getFetchMode();
         }
         $stmt->setFetchMode($fetchMode);
         return $stmt;
     }
 
     /**
      * Converts this object to an SQL SELECT string.
      *
      * @return string|null This object as a SELECT string. (or null if a string cannot be produced.)
      */
     public function assemble()
     {
         $sql = self::SQL_SELECT;
         foreach (array_keys(self::$_partsInit) as $part) {
             $method = '_render' . ucfirst($part);
             if (method_exists($this, $method)) {
                 $sql = $this->$method($sql);
             }
         }
         return $sql;
     }
 
     /**
      * Clear parts of the Select object, or an individual part.
      *
      * @param string $part OPTIONAL
      * @return Zend_Db_Select
      */
     public function reset($part = null)
     {
         if ($part == null) {
             $this->_parts = self::$_partsInit;
         } elseif (array_key_exists($part, self::$_partsInit)) {
             $this->_parts[$part] = self::$_partsInit[$part];
         }
         return $this;
     }
 
     /**
      * Gets the Zend_Db_Adapter_Abstract for this
      * particular Zend_Db_Select object.
      *
      * @return Zend_Db_Adapter_Abstract
      */
     public function getAdapter()
     {
         return $this->_adapter;
     }
 
     /**
      * Populate the {@link $_parts} 'join' key
      *
      * Does the dirty work of populating the join key.
      *
      * The $name and $cols parameters follow the same logic
      * as described in the from() method.
      *
      * @param  null|string $type Type of join; inner, left, and null are currently supported
      * @param  array|string|Zend_Db_Expr $name Table name
      * @param  string $cond Join on this condition
      * @param  array|string $cols The columns to select from the joined table
      * @param  string $schema The database name to specify, if any.
      * @return Zend_Db_Select This Zend_Db_Select object
      * @throws Zend_Db_Select_Exception
      */
     protected function _join($type, $name, $cond, $cols, $schema = null)
     {
         if (!in_array($type, self::$_joinTypes) && $type != self::FROM) {
             /**
              * @see Zend_Db_Select_Exception
              */
             // require_once 'Zend/Db/Select/Exception.php';
             throw new Zend_Db_Select_Exception("Invalid join type '$type'");
         }
 
         if (count($this->_parts[self::UNION])) {
             // require_once 'Zend/Db/Select/Exception.php';
             throw new Zend_Db_Select_Exception("Invalid use of table with " . self::SQL_UNION);
         }
 
         if (empty($name)) {
             $correlationName = $tableName = '';
         } elseif (is_array($name)) {
             // Must be array($correlationName => $tableName) or array($ident, ...)
             foreach ($name as $_correlationName => $_tableName) {
                 if (is_string($_correlationName)) {
                     // We assume the key is the correlation name and value is the table name
                     $tableName = $_tableName;
                     $correlationName = $_correlationName;
                 } else {
                     // We assume just an array of identifiers, with no correlation name
                     $tableName = $_tableName;
                     $correlationName = $this->_uniqueCorrelation($tableName);
                 }
                 break;
             }
         } elseif ($name instanceof Zend_Db_Expr|| $name instanceof Zend_Db_Select) {
             $tableName = $name;
             $correlationName = $this->_uniqueCorrelation('t');
         } elseif (preg_match('/^(.+)\s+AS\s+(.+)$/i', $name, $m)) {
             $tableName = $m[1];
             $correlationName = $m[2];
         } else {
             $tableName = $name;
             $correlationName = $this->_uniqueCorrelation($tableName);
         }
 
         // Schema from table name overrides schema argument
         if (!is_object($tableName) && false !== strpos($tableName, '.')) {
             list($schema, $tableName) = explode('.', $tableName);
         }
 
         $lastFromCorrelationName = null;
         if (!empty($correlationName)) {
             if (array_key_exists($correlationName, $this->_parts[self::FROM])) {
                 /**
                  * @see Zend_Db_Select_Exception
                  */
                 // require_once 'Zend/Db/Select/Exception.php';
                 throw new Zend_Db_Select_Exception("You cannot define a correlation name '$correlationName' more than once");
             }
 
             if ($type == self::FROM) {
                 // append this from after the last from joinType
                 $tmpFromParts = $this->_parts[self::FROM];
                 $this->_parts[self::FROM] = array();
                 // move all the froms onto the stack
                 while ($tmpFromParts) {
                     $currentCorrelationName = key($tmpFromParts);
                     if ($tmpFromParts[$currentCorrelationName]['joinType'] != self::FROM) {
                         break;
                     }
                     $lastFromCorrelationName = $currentCorrelationName;
                     $this->_parts[self::FROM][$currentCorrelationName] = array_shift($tmpFromParts);
                 }
             } else {
                 $tmpFromParts = array();
             }
             $this->_parts[self::FROM][$correlationName] = array(
                 'joinType'      => $type,
                 'schema'        => $schema,
                 'tableName'     => $tableName,
                 'joinCondition' => $cond
                 );
             while ($tmpFromParts) {
                 $currentCorrelationName = key($tmpFromParts);
                 $this->_parts[self::FROM][$currentCorrelationName] = array_shift($tmpFromParts);
             }
         }
 
         // add to the columns from this joined table
         if ($type == self::FROM && $lastFromCorrelationName == null) {
             $lastFromCorrelationName = true;
         }
         $this->_tableCols($correlationName, $cols, $lastFromCorrelationName);
 
         return $this;
     }
 
     /**
      * Handle JOIN... USING... syntax
      *
      * This is functionality identical to the existing JOIN methods, however
      * the join condition can be passed as a single column name. This method
      * then completes the ON condition by using the same field for the FROM
      * table and the JOIN table.
      *
      * <code>
      * $select = $db->select()->from('table1')
      *                        ->joinUsing('table2', 'column1');
      *
      * // SELECT * FROM table1 JOIN table2 ON table1.column1 = table2.column2
      * </code>
      *
      * These joins are called by the developer simply by adding 'Using' to the
      * method name. E.g.
      * * joinUsing
      * * joinInnerUsing
      * * joinFullUsing
      * * joinRightUsing
      * * joinLeftUsing
      *
      * @return Zend_Db_Select This Zend_Db_Select object.
      */
     public function _joinUsing($type, $name, $cond, $cols = '*', $schema = null)
     {
         if (empty($this->_parts[self::FROM])) {
             // require_once 'Zend/Db/Select/Exception.php';
             throw new Zend_Db_Select_Exception("You can only perform a joinUsing after specifying a FROM table");
         }
 
         $join  = $this->_adapter->quoteIdentifier(key($this->_parts[self::FROM]), true);
         $from  = $this->_adapter->quoteIdentifier($this->_uniqueCorrelation($name), true);
 
         $joinCond = array();
         foreach ((array)$cond as $fieldName) {
             $cond1 = $from . '.' . $fieldName;
             $cond2 = $join . '.' . $fieldName;
             $joinCond[]  = $cond1 . ' = ' . $cond2;
         }
         $cond = implode(' '.self::SQL_AND.' ', $joinCond);
 
         return $this->_join($type, $name, $cond, $cols, $schema);
     }
 
     /**
      * Generate a unique correlation name
      *
      * @param string|array $name A qualified identifier.
      * @return string A unique correlation name.
      */
     private function _uniqueCorrelation($name)
     {
         if (is_array($name)) {
             $k = key($name);
             $c = is_string($k) ? $k : end($name);
         } else {
             // Extract just the last name of a qualified table name
             $dot = strrpos($name,'.');
             $c = ($dot === false) ? $name : substr($name, $dot+1);
         }
         for ($i = 2; array_key_exists($c, $this->_parts[self::FROM]); ++$i) {
             $c = $name . '_' . (string) $i;
         }
         return $c;
     }
 
     /**
      * Adds to the internal table-to-column mapping array.
      *
      * @param  string $tbl The table/join the columns come from.
      * @param  array|string $cols The list of columns; preferably as
      * an array, but possibly as a string containing one column.
      * @param  bool|string True if it should be prepended, a correlation name if it should be inserted
      * @return void
      */
     protected function _tableCols($correlationName, $cols, $afterCorrelationName = null)
     {
         if (!is_array($cols)) {
             $cols = array($cols);
         }
 
         if ($correlationName == null) {
             $correlationName = '';
         }
 
         $columnValues = array();
 
         foreach (array_filter($cols) as $alias => $col) {
             $currentCorrelationName = $correlationName;
             if (is_string($col)) {
                 // Check for a column matching "<column> AS <alias>" and extract the alias name
                 $col = trim(str_replace("\n", ' ', $col));
                 if (preg_match('/^(.+)\s+' . self::SQL_AS . '\s+(.+)$/i', $col, $m)) {
                     $col = $m[1];
                     $alias = $m[2];
                 }
                 // Check for columns that look like functions and convert to Zend_Db_Expr
                 if (preg_match(self::REGEX_COLUMN_EXPR, (string) $col)) {
                     $col = new Zend_Db_Expr($col);
                 } elseif (preg_match('/(.+)\.(.+)/', $col, $m)) {
                     $currentCorrelationName = $m[1];
                     $col = $m[2];
                 }
             }
             $columnValues[] = array($currentCorrelationName, $col, is_string($alias) ? $alias : null);
         }
 
         if ($columnValues) {
 
             // should we attempt to prepend or insert these values?
             if ($afterCorrelationName === true || is_string($afterCorrelationName)) {
                 $tmpColumns = $this->_parts[self::COLUMNS];
                 $this->_parts[self::COLUMNS] = array();
             } else {
                 $tmpColumns = array();
             }
 
             // find the correlation name to insert after
             if (is_string($afterCorrelationName)) {
                 while ($tmpColumns) {
                     $this->_parts[self::COLUMNS][] = $currentColumn = array_shift($tmpColumns);
                     if ($currentColumn[0] == $afterCorrelationName) {
                         break;
                     }
                 }
             }
 
             // apply current values to current stack
             foreach ($columnValues as $columnValue) {
                 array_push($this->_parts[self::COLUMNS], $columnValue);
             }
 
             // finish ensuring that all previous values are applied (if they exist)
             while ($tmpColumns) {
                 array_push($this->_parts[self::COLUMNS], array_shift($tmpColumns));
             }
         }
     }
 
     /**
      * Internal function for creating the where clause
      *
      * @param string   $condition
      * @param mixed    $value  optional
      * @param string   $type   optional
      * @param boolean  $bool  true = AND, false = OR
      * @return string  clause
      */
     protected function _where($condition, $value = null, $type = null, $bool = true)
     {
         if (count($this->_parts[self::UNION])) {
             // require_once 'Zend/Db/Select/Exception.php';
             throw new Zend_Db_Select_Exception("Invalid use of where clause with " . self::SQL_UNION);
         }
 
         if ($value !== null) {
             $condition = $this->_adapter->quoteInto($condition, $value, $type);
         }
 
         $cond = "";
         if ($this->_parts[self::WHERE]) {
             if ($bool === true) {
                 $cond = self::SQL_AND . ' ';
             } else {
                 $cond = self::SQL_OR . ' ';
             }
         }
 
         return $cond . "($condition)";
     }
 
     /**
      * @return array
      */
     protected function _getDummyTable()
     {
         return array();
     }
 
     /**
      * Return a quoted schema name
      *
      * @param string   $schema  The schema name OPTIONAL
      * @return string|null
      */
     protected function _getQuotedSchema($schema = null)
     {
         if ($schema === null) {
             return null;
         }
         return $this->_adapter->quoteIdentifier($schema, true) . '.';
     }
 
     /**
      * Return a quoted table name
      *
      * @param string   $tableName        The table name
      * @param string   $correlationName  The correlation name OPTIONAL
      * @return string
      */
     protected function _getQuotedTable($tableName, $correlationName = null)
     {
         return $this->_adapter->quoteTableAs($tableName, $correlationName, true);
     }
 
     /**
      * Render DISTINCT clause
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderDistinct($sql)
     {
         if ($this->_parts[self::DISTINCT]) {
             $sql .= ' ' . self::SQL_DISTINCT;
         }
 
         return $sql;
     }
 
     /**
      * Render DISTINCT clause
      *
      * @param string   $sql SQL query
      * @return string|null
      */
     protected function _renderColumns($sql)
     {
         if (!count($this->_parts[self::COLUMNS])) {
             return null;
         }
 
         $columns = array();
         foreach ($this->_parts[self::COLUMNS] as $columnEntry) {
             list($correlationName, $column, $alias) = $columnEntry;
             if ($column instanceof Zend_Db_Expr) {
                 $columns[] = $this->_adapter->quoteColumnAs($column, $alias, true);
             } else {
                 if ($column == self::SQL_WILDCARD) {
                     $column = new Zend_Db_Expr(self::SQL_WILDCARD);
                     $alias = null;
                 }
                 if (empty($correlationName)) {
                     $columns[] = $this->_adapter->quoteColumnAs($column, $alias, true);
                 } else {
                     $columns[] = $this->_adapter->quoteColumnAs(array($correlationName, $column), $alias, true);
                 }
             }
         }
 
         return $sql . ' ' . implode(', ', $columns);
     }
 
     /**
      * Render FROM clause
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderFrom($sql)
     {
         /*
          * If no table specified, use RDBMS-dependent solution
          * for table-less query.  e.g. DUAL in Oracle.
          */
         if (empty($this->_parts[self::FROM])) {
             $this->_parts[self::FROM] = $this->_getDummyTable();
         }
 
         $from = array();
 
         foreach ($this->_parts[self::FROM] as $correlationName => $table) {
             $tmp = '';
 
             $joinType = ($table['joinType'] == self::FROM) ? self::INNER_JOIN : $table['joinType'];
 
             // Add join clause (if applicable)
             if (! empty($from)) {
                 $tmp .= ' ' . strtoupper($joinType) . ' ';
             }
 
             $tmp .= $this->_getQuotedSchema($table['schema']);
             $tmp .= $this->_getQuotedTable($table['tableName'], $correlationName);
 
             // Add join conditions (if applicable)
             if (!empty($from) && ! empty($table['joinCondition'])) {
                 $tmp .= ' ' . self::SQL_ON . ' ' . $table['joinCondition'];
             }
 
             // Add the table name and condition add to the list
             $from[] = $tmp;
         }
 
         // Add the list of all joins
         if (!empty($from)) {
             $sql .= ' ' . self::SQL_FROM . ' ' . implode("\n", $from);
         }
 
         return $sql;
     }
 
     /**
      * Render UNION query
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderUnion($sql)
     {
         if ($this->_parts[self::UNION]) {
             $parts = count($this->_parts[self::UNION]);
             foreach ($this->_parts[self::UNION] as $cnt => $union) {
                 list($target, $type) = $union;
                 if ($target instanceof Zend_Db_Select) {
                     $target = $target->assemble();
                 }
                 $sql .= $target;
                 if ($cnt < $parts - 1) {
                     $sql .= ' ' . $type . ' ';
                 }
             }
         }
 
         return $sql;
     }
 
     /**
      * Render WHERE clause
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderWhere($sql)
     {
         if ($this->_parts[self::FROM] && $this->_parts[self::WHERE]) {
             $sql .= ' ' . self::SQL_WHERE . ' ' .  implode(' ', $this->_parts[self::WHERE]);
         }
 
         return $sql;
     }
 
     /**
      * Render GROUP clause
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderGroup($sql)
     {
         if ($this->_parts[self::FROM] && $this->_parts[self::GROUP]) {
             $group = array();
             foreach ($this->_parts[self::GROUP] as $term) {
                 $group[] = $this->_adapter->quoteIdentifier($term, true);
             }
             $sql .= ' ' . self::SQL_GROUP_BY . ' ' . implode(",\n\t", $group);
         }
 
         return $sql;
     }
 
     /**
      * Render HAVING clause
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderHaving($sql)
     {
         if ($this->_parts[self::FROM] && $this->_parts[self::HAVING]) {
             $sql .= ' ' . self::SQL_HAVING . ' ' . implode(' ', $this->_parts[self::HAVING]);
         }
 
         return $sql;
     }
 
     /**
      * Render ORDER clause
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderOrder($sql)
     {
         if ($this->_parts[self::ORDER]) {
             $order = array();
             foreach ($this->_parts[self::ORDER] as $term) {
                 if (is_array($term)) {
                     if(is_numeric($term[0]) && strval(intval($term[0])) == $term[0]) {
                         $order[] = (int)trim($term[0]) . ' ' . $term[1];
                     } else {
                         $order[] = $this->_adapter->quoteIdentifier($term[0], true) . ' ' . $term[1];
                     }
                 } elseif (is_numeric($term) && strval(intval($term)) == $term) {
                     $order[] = (int)trim($term);
                 } else {
                     $order[] = $this->_adapter->quoteIdentifier($term, true);
                 }
             }
             $sql .= ' ' . self::SQL_ORDER_BY . ' ' . implode(', ', $order);
         }
 
         return $sql;
     }
 
     /**
      * Render LIMIT OFFSET clause
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderLimitoffset($sql)
     {
         $count = 0;
         $offset = 0;
 
         if (!empty($this->_parts[self::LIMIT_OFFSET])) {
             $offset = (int) $this->_parts[self::LIMIT_OFFSET];
             $count = PHP_INT_MAX;
         }
 
         if (!empty($this->_parts[self::LIMIT_COUNT])) {
             $count = (int) $this->_parts[self::LIMIT_COUNT];
         }
 
         /*
          * Add limits clause
          */
         if ($count > 0) {
             $sql = trim($this->_adapter->limit($sql, $count, $offset));
         }
 
         return $sql;
     }
 
     /**
      * Render FOR UPDATE clause
      *
      * @param string   $sql SQL query
      * @return string
      */
     protected function _renderForupdate($sql)
     {
         if ($this->_parts[self::FOR_UPDATE]) {
             $sql .= ' ' . self::SQL_FOR_UPDATE;
         }
 
         return $sql;
     }
 
     /**
      * Turn magic function calls into non-magic function calls
      * for joinUsing syntax
      *
      * @param string $method
      * @param array $args OPTIONAL Zend_Db_Table_Select query modifier
      * @return Zend_Db_Select
      * @throws Zend_Db_Select_Exception If an invalid method is called.
      */
     public function __call($method, array $args)
     {
         $matches = array();
 
         /**
          * Recognize methods for Has-Many cases:
          * findParent<Class>()
          * findParent<Class>By<Rule>()
          * Use the non-greedy pattern repeat modifier e.g. \w+?
          */
         if (preg_match('/^join([a-zA-Z]*?)Using$/', $method, $matches)) {
             $type = strtolower($matches[1]);
             if ($type) {
                 $type .= ' join';
                 if (!in_array($type, self::$_joinTypes)) {
                     // require_once 'Zend/Db/Select/Exception.php';
                     throw new Zend_Db_Select_Exception("Unrecognized method '$method()'");
                 }
                 if (in_array($type, array(self::CROSS_JOIN, self::NATURAL_JOIN))) {
                     // require_once 'Zend/Db/Select/Exception.php';
                     throw new Zend_Db_Select_Exception("Cannot perform a joinUsing with method '$method()'");
                 }
             } else {
                 $type = self::INNER_JOIN;
             }
             array_unshift($args, $type);
             return call_user_func_array(array($this, '_joinUsing'), $args);
         }
 
         // require_once 'Zend/Db/Select/Exception.php';
         throw new Zend_Db_Select_Exception("Unrecognized method '$method()'");
     }
 
     /**
      * Implements magic method.
      *
      * @return string This object as a SELECT string.
      */
     public function __toString()
     {
         try {
             $sql = $this->assemble();
         } catch (Exception $e) {
             trigger_error($e->getMessage(), E_USER_WARNING);
             $sql = '';
         }
         return (string)$sql;
     }
 
 }