dbo_oracle.php

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<?php
/* SVN FILE: $Id: dbo_oracle.php 8268 2009-08-01 19:40:52Z jperras $ */
/**
 * Oracle layer for DBO.
 *
 * Long description for file
 *
 * PHP versions 4 and 5
 *
 * CakePHP(tm) :  Rapid Development Framework (http://www.cakephp.org)
 * Copyright 2005-2008, Cake Software Foundation, Inc. (http://www.cakefoundation.org)
 *
 * Licensed under The MIT License
 * Redistributions of files must retain the above copyright notice.
 *
 * @filesource
 * @copyright     Copyright 2005-2008, Cake Software Foundation, Inc. (http://www.cakefoundation.org)
 * @link          http://www.cakefoundation.org/projects/info/cakephp CakePHP(tm) Project
 * @package       cake
 * @subpackage    cake.cake.libs.model.datasources.dbo
 * @since         CakePHP v 1.2.0.4041
 * @version       $Revision: 8268 $
 * @modifiedby    $LastChangedBy: jperras $
 * @lastmodified  $Date: 2009-08-01 15:40:52 -0400 (Sat, 01 Aug 2009) $
 * @license       http://www.opensource.org/licenses/mit-license.php The MIT License
 */
/**
 * Short description for class.
 *
 * Long description for class
 *
 * @package       cake
 * @subpackage    cake.cake.libs.model.datasources.dbo
 */
class DboOracle extends DboSource {
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access public
 */
    var $config = array();
/**
 * Enter description here...
 *
 * @var unknown_type
 */
    var $alias = '';
/**
 * Sequence names as introspected from the database
 */
    var $_sequences = array();
/**
 * Transaction in progress flag
 *
 * @var boolean
 */
    var $__transactionStarted = false;
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access public
 */
    var $columns = array(
        'primary_key' => array('name' => ''),
        'string' => array('name' => 'varchar2', 'limit' => '255'),
        'text' => array('name' => 'varchar2'),
        'integer' => array('name' => 'number'),
        'float' => array('name' => 'float'),
        'datetime' => array('name' => 'date', 'format' => 'Y-m-d H:i:s'),
        'timestamp' => array('name' => 'date', 'format' => 'Y-m-d H:i:s'),
        'time' => array('name' => 'date', 'format' => 'Y-m-d H:i:s'),
        'date' => array('name' => 'date', 'format' => 'Y-m-d H:i:s'),
        'binary' => array('name' => 'bytea'),
        'boolean' => array('name' => 'boolean'),
        'number' => array('name' => 'number'),
        'inet' => array('name' => 'inet'));
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access protected
 */
    var $connection;
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access protected
 */
    var $_limit = -1;
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access protected
 */
    var $_offset = 0;
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access protected
 */
    var $_map;
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access protected
 */
    var $_currentRow;
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access protected
 */
    var $_numRows;
/**
 * Enter description here...
 *
 * @var unknown_type
 * @access protected
 */
    var $_results;
/**
 * Last error issued by oci extension
 *
 * @var unknown_type
 */
    var $_error;
/**
 * Base configuration settings for MySQL driver
 *
 * @var array
 */
    var $_baseConfig = array(
        'persistent' => true,
        'host' => 'localhost',
        'login' => 'system',
        'password' => '',
        'database' => 'cake',
        'nls_sort' => '',
        'nls_sort' => ''
    );
/**
 * Table-sequence map
 *
 * @var unknown_type
 */
    var $_sequenceMap = array();
/**
 * Connects to the database using options in the given configuration array.
 *
 * @return boolean True if the database could be connected, else false
 * @access public
 */
    function connect() {
        $config = $this->config;
        $this->connected = false;
        $config['charset'] = !empty($config['charset']) ? $config['charset'] : null;

        if ($this->config['persistent']) {
            $connect = 'ociplogon';
        } else {
            $connect = 'ocilogon';
        }
        $this->connection = @$connect($config['login'], $config['password'], $config['database'], $config['charset']);

        if ($this->connection) {
            $this->connected = true;
            if (!empty($config['nls_sort'])) {
                $this->execute('ALTER SESSION SET NLS_SORT='.$config['nls_sort']);
            }

            if (!empty($config['nls_comp'])) {
                $this->execute('ALTER SESSION SET NLS_COMP='.$config['nls_comp']);
            }
            $this->execute("ALTER SESSION SET NLS_DATE_FORMAT='YYYY-MM-DD HH24:MI:SS'");
        } else {
            $this->connected = false;
            $this->_setError();
            return false;
        }
        return $this->connected;
    }
    /**
     * Keeps track of the most recent Oracle error
     *
     */
    function _setError($source = null, $clear = false) {
        if ($source) {
            $e = ocierror($source);
        } else {
            $e = ocierror();
        }
        $this->_error = $e['message'];
        if ($clear) {
            $this->_error = null;
        }
    }
/**
 * Sets the encoding language of the session
 *
 * @param string $lang language constant
 * @return bool
 */
    function setEncoding($lang) {
        if (!$this->execute('ALTER SESSION SET NLS_LANGUAGE='.$lang)) {
            return false;
        }
        return true;
    }
/**
 * Gets the current encoding language
 *
 * @return string language constant
 */
    function getEncoding() {
        $sql = 'SELECT VALUE FROM NLS_SESSION_PARAMETERS WHERE PARAMETER=\'NLS_LANGUAGE\'';
        if (!$this->execute($sql)) {
            return false;
        }

        if (!$row = $this->fetchRow()) {
            return false;
        }
        return $row[0]['VALUE'];
    }
/**
 * Disconnects from database.
 *
 * @return boolean True if the database could be disconnected, else false
 * @access public
 */
    function disconnect() {
        if ($this->connection) {
            $this->connected = !ocilogoff($this->connection);
            return !$this->connected;
        }
    }
/**
 * Scrape the incoming SQL to create the association map. This is an extremely
 * experimental method that creates the association maps since Oracle will not tell us.
 *
 * @param string $sql
 * @return false if sql is nor a SELECT
 * @access protected
 */
    function _scrapeSQL($sql) {
        $sql = str_replace("\"", '', $sql);
        $preFrom = preg_split('/\bFROM\b/', $sql);
        $preFrom = $preFrom[0];
        $find = array('SELECT');
        $replace = array('');
        $fieldList = trim(str_replace($find, $replace, $preFrom));
        $fields = preg_split('/,\s+/', $fieldList);//explode(', ', $fieldList);
        $lastTableName  = '';

        foreach($fields as $key => $value) {
            if ($value != 'COUNT(*) AS count') {
                if (preg_match('/\s+(\w+(\.\w+)*)$/', $value, $matches)) {
                    $fields[$key]   = $matches[1];

                    if (preg_match('/^(\w+\.)/', $value, $matches)) {
                        $fields[$key]   = $matches[1] . $fields[$key];
                        $lastTableName  = $matches[1];
                    }
                }
                /*
                if (preg_match('/(([[:alnum:]_]+)\.[[:alnum:]_]+)(\s+AS\s+(\w+))?$/i', $value, $matches)) {
                    $fields[$key]   = isset($matches[4]) ? $matches[2] . '.' . $matches[4] : $matches[1];
                }
                */
            }
        }
        $this->_map = array();

        foreach($fields as $f) {
            $e = explode('.', $f);
            if (count($e) > 1) {
                $table = $e[0];
                $field = strtolower($e[1]);
            } else {
                $table = 0;
                $field = $e[0];
            }
            $this->_map[] = array($table, $field);
        }
    }
/**
 * Modify a SQL query to limit (and offset) the result set
 *
 * @param integer $limit Maximum number of rows to return
 * @param integer $offset Row to begin returning
 * @return modified SQL Query
 * @access public
 */
    function limit($limit = -1, $offset = 0) {
        $this->_limit = (int) $limit;
        $this->_offset = (int) $offset;
    }
/**
 * Returns number of rows in previous resultset. If no previous resultset exists,
 * this returns false.
 *
 * @return integer Number of rows in resultset
 * @access public
 */
    function lastNumRows() {
        return $this->_numRows;
    }
/**
 * Executes given SQL statement. This is an overloaded method.
 *
 * @param string $sql SQL statement
 * @return resource Result resource identifier or null
 * @access protected
 */
    function _execute($sql) {
        $this->_statementId = @ociparse($this->connection, $sql);
        if (!$this->_statementId) {
            $this->_setError($this->connection);
            return false;
        }

        if ($this->__transactionStarted) {
            $mode = OCI_DEFAULT;
        } else {
            $mode = OCI_COMMIT_ON_SUCCESS;
        }

        if (!@ociexecute($this->_statementId, $mode)) {
            $this->_setError($this->_statementId);
            return false;
        }

        $this->_setError(null, true);

        switch(ocistatementtype($this->_statementId)) {
            case 'DESCRIBE':
            case 'SELECT':
                $this->_scrapeSQL($sql);
            break;
            default:
                return $this->_statementId;
            break;
        }

        if ($this->_limit >= 1) {
            ocisetprefetch($this->_statementId, $this->_limit);
        } else {
            ocisetprefetch($this->_statementId, 3000);
        }
        $this->_numRows = ocifetchstatement($this->_statementId, $this->_results, $this->_offset, $this->_limit, OCI_NUM | OCI_FETCHSTATEMENT_BY_ROW);
        $this->_currentRow = 0;
        $this->limit();
        return $this->_statementId;
    }
/**
 * Enter description here...
 *
 * @return unknown
 * @access public
 */
    function fetchRow() {
        if ($this->_currentRow >= $this->_numRows) {
            ocifreestatement($this->_statementId);
            $this->_map = null;
            $this->_results = null;
            $this->_currentRow = null;
            $this->_numRows = null;
            return false;
        }
        $resultRow = array();

        foreach($this->_results[$this->_currentRow] as $index => $field) {
            list($table, $column) = $this->_map[$index];

            if (strpos($column, ' count')) {
                $resultRow[0]['count'] = $field;
            } else {
                $resultRow[$table][$column] = $this->_results[$this->_currentRow][$index];
            }
        }
        $this->_currentRow++;
        return $resultRow;
    }
/**
 * Fetches the next row from the current result set
 *
 * @return unknown
 */
    function fetchResult() {
        return $this->fetchRow();
    }
/**
 * Checks to see if a named sequence exists
 *
 * @param string $sequence
 * @return bool
 * @access public
 */
    function sequenceExists($sequence) {
        $sql = "SELECT SEQUENCE_NAME FROM USER_SEQUENCES WHERE SEQUENCE_NAME = '$sequence'";
        if (!$this->execute($sql)) {
            return false;
        }
        return $this->fetchRow();
    }
/**
 * Creates a database sequence
 *
 * @param string $sequence
 * @return bool
 * @access public
 */
    function createSequence($sequence) {
        $sql = "CREATE SEQUENCE $sequence";
        return $this->execute($sql);
    }
/**
 * Enter description here...
 *
 * @param unknown_type $table
 * @return unknown
 * @access public
 */
    function createTrigger($table) {
        $sql = "CREATE OR REPLACE TRIGGER pk_$table" . "_trigger BEFORE INSERT ON $table FOR EACH ROW BEGIN SELECT pk_$table.NEXTVAL INTO :NEW.ID FROM DUAL; END;";
        return $this->execute($sql);
    }
/**
 * Returns an array of tables in the database. If there are no tables, an error is
 * raised and the application exits.
 *
 * @return array tablenames in the database
 * @access public
 */
    function listSources() {
        $cache = parent::listSources();
        if ($cache != null) {
            return $cache;
        }
        $sql = 'SELECT view_name AS name FROM all_views UNION SELECT table_name AS name FROM all_tables';

        if (!$this->execute($sql)) {
            return false;
        }
        $sources = array();

        while($r = $this->fetchRow()) {
            $sources[] = strtolower($r[0]['name']);
        }
        parent::listSources($sources);
        return $sources;
    }
/**
 * Returns an array of the fields in given table name.
 *
 * @param object instance of a model to inspect
 * @return array Fields in table. Keys are name and type
 * @access public
 */
    function describe(&$model) {
        $table = $model->fullTableName($model, false);

        if (!empty($model->sequence)) {
            $this->_sequenceMap[$table] = $model->sequence;
        } elseif (!empty($model->table)) {
            $this->_sequenceMap[$table] = $model->table . '_seq';
        }

        $cache = parent::describe($model);

        if ($cache != null) {
            return $cache;
        }

        $sql = 'SELECT COLUMN_NAME, DATA_TYPE, DATA_LENGTH FROM all_tab_columns WHERE table_name = \'';
        $sql .= strtoupper($this->fullTableName($model)) . '\'';

        if (!$this->execute($sql)) {
            return false;
        }

        $fields = array();

        for ($i = 0; $row = $this->fetchRow(); $i++) {
            $fields[strtolower($row[0]['COLUMN_NAME'])] = array(
                'type'=> $this->column($row[0]['DATA_TYPE']),
                'length'=> $row[0]['DATA_LENGTH']
            );
        }
        $this->__cacheDescription($this->fullTableName($model, false), $fields);

        return $fields;
    }
/**
 * Deletes all the records in a table and drops all associated auto-increment sequences.
 * Using DELETE instead of TRUNCATE because it causes locking problems.
 *
 * @param mixed $table A string or model class representing the table to be truncated
 * @param integer $reset If -1, sequences are dropped, if 0 (default), sequences are reset,
 *                      and if 1, sequences are not modified
 * @return boolean  SQL TRUNCATE TABLE statement, false if not applicable.
 * @access public
 *
 */
    function truncate($table, $reset = 0) {

        if (empty($this->_sequences)) {
            $sql = "SELECT sequence_name FROM all_sequences";
            $this->execute($sql);
            while ($row = $this->fetchRow()) {
                $this->_sequences[] = strtolower($row[0]['sequence_name']);
            }
        }

        $this->execute('DELETE FROM ' . $this->fullTableName($table));
        if (!isset($this->_sequenceMap[$table]) || !in_array($this->_sequenceMap[$table], $this->_sequences)) {
            return true;
        }
        if ($reset === 0) {
            $this->execute("SELECT {$this->_sequenceMap[$table]}.nextval FROM dual");
            $row = $this->fetchRow();
            $currval = $row[$this->_sequenceMap[$table]]['nextval'];

            $this->execute("SELECT min_value FROM all_sequences WHERE sequence_name = '{$this->_sequenceMap[$table]}'");
            $row = $this->fetchRow();
            $min_value = $row[0]['min_value'];

            if ($min_value == 1) $min_value = 0;
            $offset = -($currval - $min_value);

            $this->execute("ALTER SEQUENCE {$this->_sequenceMap[$table]} INCREMENT BY $offset MINVALUE $min_value");
            $this->execute("SELECT {$this->_sequenceMap[$table]}.nextval FROM dual");
            $this->execute("ALTER SEQUENCE {$this->_sequenceMap[$table]} INCREMENT BY 1");
        } else {
            //$this->execute("DROP SEQUENCE {$this->_sequenceMap[$table]}");
        }
        return true;
    }
/**
 * Enables, disables, and lists table constraints
 *
 * Note: This method could have been written using a subselect for each table,
 * however the effort Oracle expends to run the constraint introspection is very high.
 * Therefore, this method caches the result once and loops through the arrays to find
 * what it needs. It reduced my query time by 50%. YMMV.
 *
 * @param string $action
 * @param string $table
 * @return mixed boolean true or array of constraints
 */
    function constraint($action, $table) {
        if (empty($table)) {
            trigger_error(__('Must specify table to operate on constraints'));
        }

        $table = strtoupper($table);

        if (empty($this->_keyConstraints)) {
            $sql = "SELECT
                      table_name,
                      c.constraint_name
                    FROM all_cons_columns cc
                    LEFT JOIN all_indexes i ON (cc.constraint_name = i.index_name)
                    LEFT JOIN all_constraints c ON(c.constraint_name = cc.constraint_name)";
            $this->execute($sql);
            while ($row = $this->fetchRow()) {
                $this->_keyConstraints[] = array($row[0]['table_name'], $row['c']['constraint_name']);
            }
        }

        $relatedKeys = array();
        foreach ($this->_keyConstraints as $c) {
            if ($c[0] == $table) {
                $relatedKeys[] = $c[1];
            }
        }

        if (empty($this->_constraints)) {
            $sql = "SELECT
                      table_name,
                      constraint_name,
                      r_constraint_name
                    FROM
                      all_constraints";
            $this->execute($sql);
            while ($row = $this->fetchRow()) {
                $this->_constraints[] = $row[0];
            }
        }

        $constraints = array();
        foreach ($this->_constraints as $c) {
            if (in_array($c['r_constraint_name'], $relatedKeys)) {
                $constraints[] = array($c['table_name'], $c['constraint_name']);
            }
        }

        foreach ($constraints as $c) {
            list($table, $constraint) = $c;
            switch ($action) {
                case 'enable':
                    $this->execute("ALTER TABLE $table ENABLE CONSTRAINT $constraint");
                    break;
                case 'disable':
                    $this->execute("ALTER TABLE $table DISABLE CONSTRAINT $constraint");
                    break;
                case 'list':
                    return $constraints;
                    break;
                default:
                    trigger_error(__('DboOracle::constraint() accepts only enable, disable, or list'));
            }
        }
        return true;
    }
/**
 * Returns an array of the indexes in given table name.
 *
 * @param string $model Name of model to inspect
 * @return array Fields in table. Keys are column and unique
 */
    function index($model) {
        $index = array();
        $table = $this->fullTableName($model, false);
        if ($table) {
            $indexes = $this->query('SELECT
              cc.table_name,
              cc.column_name,
              cc.constraint_name,
              c.constraint_type,
              i.index_name,
              i.uniqueness
            FROM all_cons_columns cc
            LEFT JOIN all_indexes i ON(cc.constraint_name = i.index_name)
            LEFT JOIN all_constraints c ON(c.constraint_name = cc.constraint_name)
            WHERE cc.table_name = \'' . strtoupper($table) .'\'');
            foreach ($indexes as $i => $idx) {
                if ($idx['c']['constraint_type'] == 'P') {
                    $key = 'PRIMARY';
                } else {
                    continue;
                }
                if (!isset($index[$key])) {
                    $index[$key]['column'] = strtolower($idx['cc']['column_name']);
                    $index[$key]['unique'] = intval($idx['i']['uniqueness'] == 'UNIQUE');
                } else {
                    if (!is_array($index[$key]['column'])) {
                        $col[] = $index[$key]['column'];
                    }
                    $col[] = strtolower($idx['cc']['column_name']);
                    $index[$key]['column'] = $col;
                }
            }
        }
        return $index;
    }
/**
 * Generate a Oracle Alter Table syntax for the given Schema comparison
 *
 * @param unknown_type $schema
 * @return unknown
 */
    function alterSchema($compare, $table = null) {
        if (!is_array($compare)) {
            return false;
        }
        $out = '';
        $colList = array();
        foreach($compare as $curTable => $types) {
            if (!$table || $table == $curTable) {
                $out .= 'ALTER TABLE ' . $this->fullTableName($curTable) . " \n";
                foreach($types as $type => $column) {
                    switch($type) {
                        case 'add':
                            foreach($column as $field => $col) {
                                $col['name'] = $field;
                                $alter = 'ADD '.$this->buildColumn($col);
                                if (isset($col['after'])) {
                                    $alter .= ' AFTER '. $this->name($col['after']);
                                }
                                $colList[] = $alter;
                            }
                        break;
                        case 'drop':
                            foreach($column as $field => $col) {
                                $col['name'] = $field;
                                $colList[] = 'DROP '.$this->name($field);
                            }
                        break;
                        case 'change':
                            foreach($column as $field => $col) {
                                if (!isset($col['name'])) {
                                    $col['name'] = $field;
                                }
                                $colList[] = 'CHANGE '. $this->name($field).' '.$this->buildColumn($col);
                            }
                        break;
                    }
                }
                $out .= "\t" . join(",\n\t", $colList) . ";\n\n";
            }
        }
        return $out;
    }
/**
 * This method should quote Oracle identifiers. Well it doesn't.
 * It would break all scaffolding and all of Cake's default assumptions.
 *
 * @param unknown_type $var
 * @return unknown
 * @access public
 */
    function name($name) {
        if (strpos($name, '.') !== false && strpos($name, '"') === false) {
            list($model, $field) = explode('.', $name);
            if ($field[0] == "_") {
                $name = "$model.\"$field\"";
            }
        } else {
            if ($name[0] == "_") {
                $name = "\"$name\"";
            }
        }
        return $name;
    }
/**
 * Begin a transaction
 *
 * @param unknown_type $model
 * @return boolean True on success, false on fail
 * (i.e. if the database/model does not support transactions).
 */
    function begin() {
        $this->__transactionStarted = true;
        return true;
    }
/**
 * Rollback a transaction
 *
 * @param unknown_type $model
 * @return boolean True on success, false on fail
 * (i.e. if the database/model does not support transactions,
 * or a transaction has not started).
 */
    function rollback() {
        return ocirollback($this->connection);
    }
/**
 * Commit a transaction
 *
 * @param unknown_type $model
 * @return boolean True on success, false on fail
 * (i.e. if the database/model does not support transactions,
 * or a transaction has not started).
 */
    function commit() {
        $this->__transactionStarted = false;
        return ocicommit($this->connection);
    }
/**
 * Converts database-layer column types to basic types
 *
 * @param string $real Real database-layer column type (i.e. "varchar(255)")
 * @return string Abstract column type (i.e. "string")
 * @access public
 */
    function column($real) {
        if (is_array($real)) {
            $col = $real['name'];

            if (isset($real['limit'])) {
                $col .= '('.$real['limit'].')';
            }
            return $col;
        } else {
            $real = strtolower($real);
        }
        $col = str_replace(')', '', $real);
        $limit = null;
        if (strpos($col, '(') !== false) {
            list($col, $limit) = explode('(', $col);
        }

        if (in_array($col, array('date', 'timestamp'))) {
            return $col;
        }
        if (strpos($col, 'number') !== false) {
            return 'integer';
        }
        if (strpos($col, 'integer') !== false) {
            return 'integer';
        }
        if (strpos($col, 'char') !== false) {
            return 'string';
        }
        if (strpos($col, 'text') !== false) {
            return 'text';
        }
        if (strpos($col, 'blob') !== false) {
            return 'binary';
        }
        if (in_array($col, array('float', 'double', 'decimal'))) {
            return 'float';
        }
        if ($col == 'boolean') {
            return $col;
        }
        return 'text';
    }
/**
 * Returns a quoted and escaped string of $data for use in an SQL statement.
 *
 * @param string $data String to be prepared for use in an SQL statement
 * @return string Quoted and escaped
 * @access public
 */
    function value($data, $column = null, $safe = false) {
        $parent = parent::value($data, $column, $safe);

        if ($parent != null) {
            return $parent;
        }

        if ($data === null) {
            return 'NULL';
        }

        if ($data === '') {
            return  "''";
        }

        switch($column) {
            case 'date':
                $data = date('Y-m-d H:i:s', strtotime($data));
                $data = "TO_DATE('$data', 'YYYY-MM-DD HH24:MI:SS')";
            break;
            case 'integer' :
            case 'float' :
            case null :
                if (is_numeric($data)) {
                    break;
                }
            default:
                $data = str_replace("'", "''", $data);
                $data = "'$data'";
            break;
        }
        return $data;
    }
/**
 * Returns the ID generated from the previous INSERT operation.
 *
 * @param string
 * @return integer
 * @access public
 */
    function lastInsertId($source) {
        $sequence = $this->_sequenceMap[$source];
        $sql = "SELECT $sequence.currval FROM dual";

        if (!$this->execute($sql)) {
            return false;
        }

        while($row = $this->fetchRow()) {
            return $row[$sequence]['currval'];
        }
        return false;
    }
/**
 * Returns a formatted error message from previous database operation.
 *
 * @return string Error message with error number
 * @access public
 */
    function lastError() {
        return $this->_error;
    }
/**
 * Returns number of affected rows in previous database operation. If no previous operation exists, this returns false.
 *
 * @return int Number of affected rows
 * @access public
 */
    function lastAffected() {
        return $this->_statementId ? ocirowcount($this->_statementId): false;
    }
/**
 * Renders a final SQL statement by putting together the component parts in the correct order
 *
 * @param string $type
 * @param array $data
 * @return string
 */
    function renderStatement($type, $data) {
        extract($data);
        $aliases = null;

        switch (strtolower($type)) {
            case 'select':
                return "SELECT {$fields} FROM {$table} {$alias} {$joins} {$conditions} {$order} {$limit}";
            break;
            case 'create':
                return "INSERT INTO {$table} ({$fields}) VALUES ({$values})";
            break;
            case 'update':
                if (!empty($alias)) {
                    $aliases = "{$this->alias}{$alias} ";
                }
                return "UPDATE {$table} {$aliases}SET {$fields} {$conditions}";
            break;
            case 'delete':
                if (!empty($alias)) {
                    $aliases = "{$this->alias}{$alias} ";
                }
                return "DELETE FROM {$table} {$aliases}{$conditions}";
            break;
            case 'schema':
                foreach (array('columns', 'indexes') as $var) {
                    if (is_array(${$var})) {
                        ${$var} = "\t" . join(",\n\t", array_filter(${$var}));
                    }
                }
                if (trim($indexes) != '') {
                    $columns .= ',';
                }
                return "CREATE TABLE {$table} (\n{$columns}{$indexes})";
            break;
            case 'alter':
                break;
        }
    }
/**
 * Enter description here...
 *
 * @param Model $model
 * @param unknown_type $linkModel
 * @param string $type Association type
 * @param unknown_type $association
 * @param unknown_type $assocData
 * @param unknown_type $queryData
 * @param unknown_type $external
 * @param unknown_type $resultSet
 * @param integer $recursive Number of levels of association
 * @param array $stack
 */
    function queryAssociation(&$model, &$linkModel, $type, $association, $assocData, &$queryData, $external = false, &$resultSet, $recursive, $stack) {
        if ($query = $this->generateAssociationQuery($model, $linkModel, $type, $association, $assocData, $queryData, $external, $resultSet)) {
            if (!isset($resultSet) || !is_array($resultSet)) {
                if (Configure::read() > 0) {
                    echo '<div style = "font: Verdana bold 12px; color: #FF0000">' . sprintf(__('SQL Error in model %s:', true), $model->alias) . ' ';
                    if (isset($this->error) && $this->error != null) {
                        echo $this->error;
                    }
                    echo '</div>';
                }
                return null;
            }
            $count = count($resultSet);

            if ($type === 'hasMany' && (!isset($assocData['limit']) || empty($assocData['limit']))) {
                $ins = $fetch = array();
                for ($i = 0; $i < $count; $i++) {
                    if ($in = $this->insertQueryData('{$__cakeID__$}', $resultSet[$i], $association, $assocData, $model, $linkModel, $stack)) {
                        $ins[] = $in;
                    }
                }

                if (!empty($ins)) {
                    $fetch = array();
                    $ins = array_chunk($ins, 1000);
                    foreach ($ins as $i) {
                        $q = str_replace('{$__cakeID__$}', join(', ', $i), $query);
                        $q = str_replace('= (', 'IN (', $q);
                        $res = $this->fetchAll($q, $model->cacheQueries, $model->alias);
                        $fetch = array_merge($fetch, $res);
                    }
                }

                if (!empty($fetch) && is_array($fetch)) {
                    if ($recursive > 0) {

                        foreach ($linkModel->__associations as $type1) {
                            foreach ($linkModel->{$type1} as $assoc1 => $assocData1) {
                                $deepModel =& $linkModel->{$assoc1};
                                $tmpStack = $stack;
                                $tmpStack[] = $assoc1;

                                if ($linkModel->useDbConfig === $deepModel->useDbConfig) {
                                    $db =& $this;
                                } else {
                                    $db =& ConnectionManager::getDataSource($deepModel->useDbConfig);
                                }
                                $db->queryAssociation($linkModel, $deepModel, $type1, $assoc1, $assocData1, $queryData, true, $fetch, $recursive - 1, $tmpStack);
                            }
                        }
                    }
                }
                return $this->__mergeHasMany($resultSet, $fetch, $association, $model, $linkModel, $recursive);
            } elseif ($type === 'hasAndBelongsToMany') {
                $ins = $fetch = array();
                for ($i = 0; $i < $count; $i++) {
                    if ($in = $this->insertQueryData('{$__cakeID__$}', $resultSet[$i], $association, $assocData, $model, $linkModel, $stack)) {
                        $ins[] = $in;
                    }
                }

                $foreignKey = $model->hasAndBelongsToMany[$association]['foreignKey'];
                $joinKeys = array($foreignKey, $model->hasAndBelongsToMany[$association]['associationForeignKey']);
                list($with, $habtmFields) = $model->joinModel($model->hasAndBelongsToMany[$association]['with'], $joinKeys);
                $habtmFieldsCount = count($habtmFields);

                if (!empty($ins)) {
                    $fetch = array();
                    $ins = array_chunk($ins, 1000);
                    foreach ($ins as $i) {
                        $q = str_replace('{$__cakeID__$}', '(' .join(', ', $i) .')', $query);
                        $q = str_replace('= (', 'IN (', $q);
                        $q = str_replace('  WHERE 1 = 1', '', $q);


                        $q = $this->insertQueryData($q, null, $association, $assocData, $model, $linkModel, $stack);
                        if ($q != false) {
                            $res = $this->fetchAll($q, $model->cacheQueries, $model->alias);
                            $fetch = array_merge($fetch, $res);
                        }
                    }
                }
            }

            for ($i = 0; $i < $count; $i++) {
                $row =& $resultSet[$i];

                if ($type !== 'hasAndBelongsToMany') {
                    $q = $this->insertQueryData($query, $resultSet[$i], $association, $assocData, $model, $linkModel, $stack);
                    if ($q != false) {
                        $fetch = $this->fetchAll($q, $model->cacheQueries, $model->alias);
                    } else {
                        $fetch = null;
                    }
                }

                if (!empty($fetch) && is_array($fetch)) {
                    if ($recursive > 0) {

                        foreach ($linkModel->__associations as $type1) {
                            foreach ($linkModel->{$type1} as $assoc1 => $assocData1) {

                                $deepModel =& $linkModel->{$assoc1};
                                if (($type1 === 'belongsTo') || ($deepModel->alias === $model->alias && $type === 'belongsTo') || ($deepModel->alias != $model->alias)) {
                                    $tmpStack = $stack;
                                    $tmpStack[] = $assoc1;
                                    if ($linkModel->useDbConfig == $deepModel->useDbConfig) {
                                        $db =& $this;
                                    } else {
                                        $db =& ConnectionManager::getDataSource($deepModel->useDbConfig);
                                    }
                                    $db->queryAssociation($linkModel, $deepModel, $type1, $assoc1, $assocData1, $queryData, true, $fetch, $recursive - 1, $tmpStack);
                                }
                            }
                        }
                    }
                    if ($type == 'hasAndBelongsToMany') {
                        $merge = array();
                        foreach($fetch as $j => $data) {
                            if (isset($data[$with]) && $data[$with][$foreignKey] === $row[$model->alias][$model->primaryKey]) {
                                if ($habtmFieldsCount > 2) {
                                    $merge[] = $data;
                                } else {
                                    $merge[] = Set::diff($data, array($with => $data[$with]));
                                }
                            }
                        }
                        if (empty($merge) && !isset($row[$association])) {
                            $row[$association] = $merge;
                        } else {
                            $this->__mergeAssociation($resultSet[$i], $merge, $association, $type);
                        }
                    } else {
                        $this->__mergeAssociation($resultSet[$i], $fetch, $association, $type);
                    }
                    $resultSet[$i][$association] = $linkModel->afterfind($resultSet[$i][$association]);

                } else {
                    $tempArray[0][$association] = false;
                    $this->__mergeAssociation($resultSet[$i], $tempArray, $association, $type);
                }
            }
        }
    }
    /**
     * Generate a "drop table" statement for the given Schema object
     *
     * @param object $schema An instance of a subclass of CakeSchema
     * @param string $table Optional.  If specified only the table name given will be generated.
     *                      Otherwise, all tables defined in the schema are generated.
     * @return string
     */
        function dropSchema($schema, $table = null) {
            if (!is_a($schema, 'CakeSchema')) {
                trigger_error(__('Invalid schema object', true), E_USER_WARNING);
                return null;
            }
            $out = '';

            foreach ($schema->tables as $curTable => $columns) {
                if (!$table || $table == $curTable) {
                    $out .= 'DROP TABLE ' . $this->fullTableName($curTable) . "\n";
                }
            }
            return $out;
        }
}
?>

---