DB_query_builder.php

<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2018, British Columbia Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package	CodeIgniter
 * @author	EllisLab Dev Team
 * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
 * @copyright	Copyright (c) 2014 - 2018, British Columbia Institute of Technology (http://bcit.ca/)
 * @license	http://opensource.org/licenses/MIT	MIT License
 * @link	https://codeigniter.com
 * @since	Version 1.0.0
 * @filesource
 */
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * Query Builder Class
 *
 * This is the platform-independent base Query Builder implementation class.
 *
 * @package		CodeIgniter
 * @subpackage	Drivers
 * @category	Database
 * @author		EllisLab Dev Team
 * @link		https://codeigniter.com/user_guide/database/
 */

abstract class CI_DB_query_builder extends CI_DB_driver {

	/**
	 * Return DELETE SQL flag
	 *
	 * @var	bool
	 */
	protected $return_delete_sql		= FALSE;

	/**
	 * Reset DELETE data flag
	 *
	 * @var	bool
	 */
	protected $reset_delete_data		= FALSE;

	/**
	 * QB SELECT data
	 *
	 * @var	array
	 */
	protected $qb_select			= array();

	/**
	 * QB DISTINCT flag
	 *
	 * @var	bool
	 */
	protected $qb_distinct			= FALSE;

	/**
	 * QB FROM data
	 *
	 * @var	array
	 */
	protected $qb_from			= array();

	/**
	 * QB JOIN data
	 *
	 * @var	array
	 */
	protected $qb_join			= array();

	/**
	 * QB WHERE data
	 *
	 * @var	array
	 */
	protected $qb_where			= array();

	/**
	 * QB GROUP BY data
	 *
	 * @var	array
	 */
	protected $qb_groupby			= array();

	/**
	 * QB HAVING data
	 *
	 * @var	array
	 */
	protected $qb_having			= array();

	/**
	 * QB keys
	 *
	 * @var	array
	 */
	protected $qb_keys			= array();

	/**
	 * QB LIMIT data
	 *
	 * @var	int
	 */
	protected $qb_limit			= FALSE;

	/**
	 * QB OFFSET data
	 *
	 * @var	int
	 */
	protected $qb_offset			= FALSE;

	/**
	 * QB ORDER BY data
	 *
	 * @var	array
	 */
	protected $qb_orderby			= array();

	/**
	 * QB data sets
	 *
	 * @var	array
	 */
	protected $qb_set			= array();

	/**
	 * QB data set for update_batch()
	 *
	 * @var	array
	 */
	protected $qb_set_ub			= array();

	/**
	 * QB aliased tables list
	 *
	 * @var	array
	 */
	protected $qb_aliased_tables		= array();

	/**
	 * QB WHERE group started flag
	 *
	 * @var	bool
	 */
	protected $qb_where_group_started	= FALSE;

	/**
	 * QB WHERE group count
	 *
	 * @var	int
	 */
	protected $qb_where_group_count		= 0;

	// Query Builder Caching variables

	/**
	 * QB Caching flag
	 *
	 * @var	bool
	 */
	protected $qb_caching				= FALSE;

	/**
	 * QB Cache exists list
	 *
	 * @var	array
	 */
	protected $qb_cache_exists			= array();

	/**
	 * QB Cache SELECT data
	 *
	 * @var	array
	 */
	protected $qb_cache_select			= array();

	/**
	 * QB Cache FROM data
	 *
	 * @var	array
	 */
	protected $qb_cache_from			= array();

	/**
	 * QB Cache JOIN data
	 *
	 * @var	array
	 */
	protected $qb_cache_join			= array();

	/**
	 * QB Cache aliased tables list
	 *
	 * @var	array
	 */
	protected $qb_cache_aliased_tables			= array();

	/**
	 * QB Cache WHERE data
	 *
	 * @var	array
	 */
	protected $qb_cache_where			= array();

	/**
	 * QB Cache GROUP BY data
	 *
	 * @var	array
	 */
	protected $qb_cache_groupby			= array();

	/**
	 * QB Cache HAVING data
	 *
	 * @var	array
	 */
	protected $qb_cache_having			= array();

	/**
	 * QB Cache ORDER BY data
	 *
	 * @var	array
	 */
	protected $qb_cache_orderby			= array();

	/**
	 * QB Cache data sets
	 *
	 * @var	array
	 */
	protected $qb_cache_set				= array();

	/**
	 * QB No Escape data
	 *
	 * @var	array
	 */
	protected $qb_no_escape 			= array();

	/**
	 * QB Cache No Escape data
	 *
	 * @var	array
	 */
	protected $qb_cache_no_escape			= array();

	// --------------------------------------------------------------------

	/**
	 * Select
	 *
	 * Generates the SELECT portion of the query
	 *
	 * @param	string
	 * @param	mixed
	 * @return	CI_DB_query_builder
	 */
	public function select($select = '*', $escape = NULL)
	{
		if (is_string($select))
		{
			$select = explode(',', $select);
		}

		// If the escape value was not set, we will base it on the global setting
		is_bool($escape) OR $escape = $this->_protect_identifiers;

		foreach ($select as $val)
		{
			$val = trim($val);

			if ($val !== '')
			{
				$this->qb_select[] = $val;
				$this->qb_no_escape[] = $escape;

				if ($this->qb_caching === TRUE)
				{
					$this->qb_cache_select[] = $val;
					$this->qb_cache_exists[] = 'select';
					$this->qb_cache_no_escape[] = $escape;
				}
			}
		}

		return $this;
	}

	// --------------------------------------------------------------------

	/**
	 * Select Max
	 *
	 * Generates a SELECT MAX(field) portion of a query
	 *
	 * @param	string	the field
	 * @param	string	an alias
	 * @return	CI_DB_query_builder
	 */
	public function select_max($select = '', $alias = '')
	{
		return $this->_max_min_avg_sum($select, $alias, 'MAX');
	}

	// --------------------------------------------------------------------

	/**
	 * Select Min
	 *
	 * Generates a SELECT MIN(field) portion of a query
	 *
	 * @param	string	the field
	 * @param	string	an alias
	 * @return	CI_DB_query_builder
	 */
	public function select_min($select = '', $alias = '')
	{
		return $this->_max_min_avg_sum($select, $alias, 'MIN');
	}

	// --------------------------------------------------------------------

	/**
	 * Select Average
	 *
	 * Generates a SELECT AVG(field) portion of a query
	 *
	 * @param	string	the field
	 * @param	string	an alias
	 * @return	CI_DB_query_builder
	 */
	public function select_avg($select = '', $alias = '')
	{
		return $this->_max_min_avg_sum($select, $alias, 'AVG');
	}

	// --------------------------------------------------------------------

	/**
	 * Select Sum
	 *
	 * Generates a SELECT SUM(field) portion of a query
	 *
	 * @param	string	the field
	 * @param	string	an alias
	 * @return	CI_DB_query_builder
	 */
	public function select_sum($select = '', $alias = '')
	{
		return $this->_max_min_avg_sum($select, $alias, 'SUM');
	}

	// --------------------------------------------------------------------

	/**
	 * SELECT [MAX|MIN|AVG|SUM]()
	 *
	 * @used-by	select_max()
	 * @used-by	select_min()
	 * @used-by	select_avg()
	 * @used-by	select_sum()
	 *
	 * @param	string	$select	Field name
	 * @param	string	$alias
	 * @param	string	$type
	 * @return	CI_DB_query_builder
	 */
	protected function _max_min_avg_sum($select = '', $alias = '', $type = 'MAX')
	{
		if ( ! is_string($select) OR $select === '')
		{
			$this->display_error('db_invalid_query');
		}

		$type = strtoupper($type);

		if ( ! in_array($type, array('MAX', 'MIN', 'AVG', 'SUM')))
		{
			show_error('Invalid function type: '.$type);
		}

		if ($alias === '')
		{
			$alias = $this->_create_alias_from_table(trim($select));
		}

		$sql = $type.'('.$this->protect_identifiers(trim($select)).') AS '.$this->escape_identifiers(trim($alias));

		$this->qb_select[] = $sql;
		$this->qb_no_escape[] = NULL;

		if ($this->qb_caching === TRUE)
		{
			$this->qb_cache_select[] = $sql;
			$this->qb_cache_exists[] = 'select';
		}

		return $this;
	}

	// --------------------------------------------------------------------

	/**
	 * Determines the alias name based on the table
	 *
	 * @param	string	$item
	 * @return	string
	 */
	protected function _create_alias_from_table($item)
	{
		if (strpos($item, '.') !== FALSE)
		{
			$item = explode('.', $item);
			return end($item);
		}

		return $item;
	}

	// --------------------------------------------------------------------

	/**
	 * DISTINCT
	 *
	 * Sets a flag which tells the query string compiler to add DISTINCT
	 *
	 * @param	bool	$val
	 * @return	CI_DB_query_builder
	 */
	public function distinct($val = TRUE)
	{
		$this->qb_distinct = is_bool($val) ? $val : TRUE;
		return $this;
	}

	// --------------------------------------------------------------------

	/**
	 * From
	 *
	 * Generates the FROM portion of the query
	 *
	 * @param	mixed	$from	can be a string or array
	 * @return	CI_DB_query_builder
	 */
	public function from($from)
	{
		foreach ((array) $from as $val)
		{
			if (strpos($val, ',') !== FALSE)
			{
				foreach (explode(',', $val) as $v)
				{
					$v = trim($v);
					$this->_track_aliases($v);

					$this->qb_from[] = $v = $this->protect_identifiers($v, TRUE, NULL, FALSE);

					if ($this->qb_caching === TRUE)
					{
						$this->qb_cache_from[] = $v;
						$this->qb_cache_exists[] = 'from';
					}
				}
			}
			else
			{
				$val = trim($val);

				// Extract any aliases that might exist. We use this information
				// in the protect_identifiers to know whether to add a table prefix
				$this->_track_aliases($val);

				$this->qb_from[] = $val = $this->protect_identifiers($val, TRUE, NULL, FALSE);

				if ($this->qb_caching === TRUE)
				{
					$this->qb_cache_from[] = $val;
					$this->qb_cache_exists[] = 'from';
				}
			}
		}

		return $this;
	}

	// --------------------------------------------------------------------

	/**
	 * JOIN
	 *
	 * Generates the JOIN portion of the query
	 *
	 * @param	string
	 * @param	string	the join condition
	 * @param	string	the type of join
	 * @param	string	whether not to try to escape identifiers
	 * @return	CI_DB_query_builder
	 */
	public function join($table, $cond, $type = '', $escape = NULL)
	{
		if ($type !== '')
		{
			$type = strtoupper(trim($type));

			if ( ! in_array($type, array('LEFT', 'RIGHT', 'OUTER', 'INNER', 'LEFT OUTER', 'RIGHT OUTER'), TRUE))
			{
				$type = '';
			}
			else
			{
				$type .= ' ';
			}
		}

		// Extract any aliases that might exist. We use this information
		// in the protect_identifiers to know whether to add a table prefix
		$this->_track_aliases($table);

		is_bool($escape) OR $escape = $this->_protect_identifiers;

		if ( ! $this->_has_operator($cond))
		{
			$cond = ' USING ('.($escape ? $this->escape_identifiers($cond) : $cond).')';
		}
		elseif ($escape === FALSE)
		{
			$cond = ' ON '.$cond;
		}
		else
		{
			// Split multiple conditions
			if (preg_match_all('/\sAND\s|\sOR\s/i', $cond, $joints, PREG_OFFSET_CAPTURE))
			{
				$conditions = array();
				$joints = $joints[0];
				array_unshift($joints, array('', 0));

				for ($i = count($joints) - 1, $pos = strlen($cond); $i >= 0; $i--)
				{
					$joints[$i][1] += strlen($joints[$i][0]); // offset
					$conditions[$i] = substr($cond, $joints[$i][1], $pos - $joints[$i][1]);
					$pos = $joints[$i][1] - strlen($joints[$i][0]);
					$joints[$i] = $joints[$i][0];
				}
			}
			else
			{
				$conditions = array($cond);
				$joints = array('');
			}

			$cond = ' ON ';
			for ($i = 0, $c = count($conditions); $i < $c; $i++)
			{
				$operator = $this->_get_operator($conditions[$i]);
				$cond .= $joints[$i];
				$cond .= preg_match("/(\(*)?([\[\]\w\.'-]+)".preg_quote($operator)."(.*)/i", $conditions[$i], $match)
					? $match[1].$this->protect_identifiers($match[2]).$operator.$this->protect_identifiers($match[3])
					: $conditions[$i];
			}
		}

		// Do we want to escape the table name?
		if ($escape === TRUE)
		{
			$table = $this->protect_identifiers($table, TRUE, NULL, FALSE);
		}

		// Assemble the JOIN statement
		$this->qb_join[] = $join = $type.'JOIN '.$table.$cond;

		if ($this->qb_caching === TRUE)
		{
			$this->qb_cache_join[] = $join;
			$this->qb_cache_exists[] = 'join';
		}

		return $this;
	}

	// --------------------------------------------------------------------

	/**
	 * WHERE
	 *
	 * Generates the WHERE portion of the query.
	 * Separates multiple calls with 'AND'.
	 *
	 * @param	mixed
	 * @param	mixed
	 * @param	bool
	 * @return	CI_DB_query_builder
	 */
	public function where($key, $value = NULL, $escape = NULL)
	{
		return $this->_wh('qb_where', $key, $value, 'AND ', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * OR WHERE
	 *
	 * Generates the WHERE portion of the query.
	 * Separates multiple calls with 'OR'.
	 *
	 * @param	mixed
	 * @param	mixed
	 * @param	bool
	 * @return	CI_DB_query_builder
	 */
	public function or_where($key, $value = NULL, $escape = NULL)
	{
		return $this->_wh('qb_where', $key, $value, 'OR ', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * WHERE, HAVING
	 *
	 * @used-by	where()
	 * @used-by	or_where()
	 * @used-by	having()
	 * @used-by	or_having()
	 *
	 * @param	string	$qb_key	'qb_where' or 'qb_having'
	 * @param	mixed	$key
	 * @param	mixed	$value
	 * @param	string	$type
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	protected function _wh($qb_key, $key, $value = NULL, $type = 'AND ', $escape = NULL)
	{
		$qb_cache_key = ($qb_key === 'qb_having') ? 'qb_cache_having' : 'qb_cache_where';

		if ( ! is_array($key))
		{
			$key = array($key => $value);
		}

		// If the escape value was not set will base it on the global setting
		is_bool($escape) OR $escape = $this->_protect_identifiers;

		foreach ($key as $k => $v)
		{
			$prefix = (count($this->$qb_key) === 0 && count($this->$qb_cache_key) === 0)
				? $this->_group_get_type('')
				: $this->_group_get_type($type);

			if ($v !== NULL)
			{
				if ($escape === TRUE)
				{
					$v = $this->escape($v);
				}

				if ( ! $this->_has_operator($k))
				{
					$k .= ' = ';
				}
			}
			elseif ( ! $this->_has_operator($k))
			{
				// value appears not to have been set, assign the test to IS NULL
				$k .= ' IS NULL';
			}
			elseif (preg_match('/\s*(!?=|<>|\sIS(?:\s+NOT)?\s)\s*$/i', $k, $match, PREG_OFFSET_CAPTURE))
			{
				$k = substr($k, 0, $match[0][1]).($match[1][0] === '=' ? ' IS NULL' : ' IS NOT NULL');
			}

			${$qb_key} = array('condition' => $prefix.$k, 'value' => $v, 'escape' => $escape);
			$this->{$qb_key}[] = ${$qb_key};
			if ($this->qb_caching === TRUE)
			{
				$this->{$qb_cache_key}[] = ${$qb_key};
				$this->qb_cache_exists[] = substr($qb_key, 3);
			}

		}

		return $this;
	}

	// --------------------------------------------------------------------

	/**
	 * WHERE IN
	 *
	 * Generates a WHERE field IN('item', 'item') SQL query,
	 * joined with 'AND' if appropriate.
	 *
	 * @param	string	$key	The field to search
	 * @param	array	$values	The values searched on
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	public function where_in($key = NULL, $values = NULL, $escape = NULL)
	{
		return $this->_where_in($key, $values, FALSE, 'AND ', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * OR WHERE IN
	 *
	 * Generates a WHERE field IN('item', 'item') SQL query,
	 * joined with 'OR' if appropriate.
	 *
	 * @param	string	$key	The field to search
	 * @param	array	$values	The values searched on
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	public function or_where_in($key = NULL, $values = NULL, $escape = NULL)
	{
		return $this->_where_in($key, $values, FALSE, 'OR ', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * WHERE NOT IN
	 *
	 * Generates a WHERE field NOT IN('item', 'item') SQL query,
	 * joined with 'AND' if appropriate.
	 *
	 * @param	string	$key	The field to search
	 * @param	array	$values	The values searched on
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	public function where_not_in($key = NULL, $values = NULL, $escape = NULL)
	{
		return $this->_where_in($key, $values, TRUE, 'AND ', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * OR WHERE NOT IN
	 *
	 * Generates a WHERE field NOT IN('item', 'item') SQL query,
	 * joined with 'OR' if appropriate.
	 *
	 * @param	string	$key	The field to search
	 * @param	array	$values	The values searched on
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	public function or_where_not_in($key = NULL, $values = NULL, $escape = NULL)
	{
		return $this->_where_in($key, $values, TRUE, 'OR ', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * Internal WHERE IN
	 *
	 * @used-by	where_in()
	 * @used-by	or_where_in()
	 * @used-by	where_not_in()
	 * @used-by	or_where_not_in()
	 *
	 * @param	string	$key	The field to search
	 * @param	array	$values	The values searched on
	 * @param	bool	$not	If the statement would be IN or NOT IN
	 * @param	string	$type
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	protected function _where_in($key = NULL, $values = NULL, $not = FALSE, $type = 'AND ', $escape = NULL)
	{
		if ($key === NULL OR $values === NULL)
		{
			return $this;
		}

		if ( ! is_array($values))
		{
			$values = array($values);
		}

		is_bool($escape) OR $escape = $this->_protect_identifiers;

		$not = ($not) ? ' NOT' : '';

		if ($escape === TRUE)
		{
			$where_in = array();
			foreach ($values as $value)
			{
				$where_in[] = $this->escape($value);
			}
		}
		else
		{
			$where_in = array_values($values);
		}

		$prefix = (count($this->qb_where) === 0 && count($this->qb_cache_where) === 0)
			? $this->_group_get_type('')
			: $this->_group_get_type($type);

		$where_in = array(
			'condition' => $prefix.$key.$not.' IN('.implode(', ', $where_in).')',
			'value' => NULL,
			'escape' => $escape
		);

		$this->qb_where[] = $where_in;
		if ($this->qb_caching === TRUE)
		{
			$this->qb_cache_where[] = $where_in;
			$this->qb_cache_exists[] = 'where';
		}

		return $this;
	}

	// --------------------------------------------------------------------

	/**
	 * LIKE
	 *
	 * Generates a %LIKE% portion of the query.
	 * Separates multiple calls with 'AND'.
	 *
	 * @param	mixed	$field
	 * @param	string	$match
	 * @param	string	$side
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	public function like($field, $match = '', $side = 'both', $escape = NULL)
	{
		return $this->_like($field, $match, 'AND ', $side, '', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * NOT LIKE
	 *
	 * Generates a NOT LIKE portion of the query.
	 * Separates multiple calls with 'AND'.
	 *
	 * @param	mixed	$field
	 * @param	string	$match
	 * @param	string	$side
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	public function not_like($field, $match = '', $side = 'both', $escape = NULL)
	{
		return $this->_like($field, $match, 'AND ', $side, 'NOT', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * OR LIKE
	 *
	 * Generates a %LIKE% portion of the query.
	 * Separates multiple calls with 'OR'.
	 *
	 * @param	mixed	$field
	 * @param	string	$match
	 * @param	string	$side
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	public function or_like($field, $match = '', $side = 'both', $escape = NULL)
	{
		return $this->_like($field, $match, 'OR ', $side, '', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * OR NOT LIKE
	 *
	 * Generates a NOT LIKE portion of the query.
	 * Separates multiple calls with 'OR'.
	 *
	 * @param	mixed	$field
	 * @param	string	$match
	 * @param	string	$side
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	public function or_not_like($field, $match = '', $side = 'both', $escape = NULL)
	{
		return $this->_like($field, $match, 'OR ', $side, 'NOT', $escape);
	}

	// --------------------------------------------------------------------

	/**
	 * Internal LIKE
	 *
	 * @used-by	like()
	 * @used-by	or_like()
	 * @used-by	not_like()
	 * @used-by	or_not_like()
	 *
	 * @param	mixed	$field
	 * @param	string	$match
	 * @param	string	$type
	 * @param	string	$side
	 * @param	string	$not
	 * @param	bool	$escape
	 * @return	CI_DB_query_builder
	 */
	protected function _like($field, $match = '', $type = 'AND ', $side = 'both', $not = '', $escape = NULL)
	{
		if ( ! is_array($field))
		{
			$field = array($field => $match);
		}

		is_bool($escape) OR $escape = $this->_protect_identifiers;
		// lowercase $side in case somebody writes e.g. 'BEFORE' instead of 'before' (doh)
		$side = strtolower($side);

		foreach ($field as $k => $v)
		{
			$prefix = (count($this->qb_where) === 0 && count($this->qb_cache_where) === 0)
				? $this->_group_get_type('') : $this->_group_get_type($type);

			if ($escape === TRUE)
			{
				$v = $this->escape_like_str($v);
			}

			switch ($side)
			{
				case 'none':
					$v = "'{$v}'";
					break;
				case 'before':
					$v = "%'{$v}'";
					break;
				case 'after':
					$v = "'{$v}%'";
					break;
				case 'both':
				default:
					$v = "'%{$v}%'";
					break;
			}

			// some platforms require an escape sequence definition for LIKE wildcards
			if ($escape === TRUE && $this->_like_escape_str !== '')
			{
				$v .= sprintf($this->_like_escape_str, $this->_like_escape_chr);
			}

			$qb_where = array('condition' => "{$prefix} {$k} {$not} LIKE", 'value' => $v, 'escape' => $escape);
			$this->qb_where[] = $qb_where;
			if ($this->qb_caching === TRUE)
			{
				$this->qb_cache_where[] = $qb_where;
				$this->qb_cache_exists[] = 'where';
			}
		}

		return $this;
	}