dbo_sqlite.php

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<?php
/* SVN FILE: $Id: dbo_sqlite.php 8184 2009-06-02 03:03:51Z mark_story $ */
/**
 * SQLite 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(tm) v 0.9.0
 * @version       $Revision: 8184 $
 * @modifiedby    $LastChangedBy: mark_story $
 * @lastmodified  $Date: 2009-06-01 23:03:51 -0400 (Mon, 01 Jun 2009) $
 * @license       http://www.opensource.org/licenses/mit-license.php The MIT License
 */
/**
 * DBO implementation for the SQLite DBMS.
 *
 * Long description for class
 *
 * @package       cake
 * @subpackage    cake.cake.libs.model.datasources.dbo
 */
class DboSqlite extends DboSource {
/**
 * Enter description here...
 *
 * @var unknown_type
 */
    var $description = "SQLite DBO Driver";
/**
 * Opening quote for quoted identifiers
 *
 * @var string
 */
    var $startQuote = '"';
/**
 * Closing quote for quoted identifiers
 *
 * @var string
 */
    var $endQuote = '"';
/**
 * Keeps the transaction statistics of CREATE/UPDATE/DELETE queries
 *
 * @var array
 * @access protected
 */
    var $_queryStats = array();
/**
 * Base configuration settings for SQLite driver
 *
 * @var array
 */
    var $_baseConfig = array(
        'persistent' => true,
        'database' => null,
        'connect' => 'sqlite_popen'
    );
/**
 * Index of basic SQL commands
 *
 * @var array
 * @access protected
 */
    var $_commands = array(
        'begin'    => 'BEGIN TRANSACTION',
        'commit'   => 'COMMIT TRANSACTION',
        'rollback' => 'ROLLBACK TRANSACTION'
    );
/**
 * SQLite column definition
 *
 * @var array
 */
    var $columns = array(
        'primary_key' => array('name' => 'integer primary key'),
        'string' => array('name' => 'varchar', 'limit' => '255'),
        'text' => array('name' => 'text'),
        'integer' => array('name' => 'integer', 'limit' => 11, 'formatter' => 'intval'),
        'float' => array('name' => 'float', 'formatter' => 'floatval'),
        'datetime' => array('name' => 'datetime', 'format' => 'Y-m-d H:i:s', 'formatter' => 'date'),
        'timestamp' => array('name' => 'timestamp', 'format' => 'Y-m-d H:i:s', 'formatter' => 'date'),
        'time' => array('name' => 'time', 'format' => 'H:i:s', 'formatter' => 'date'),
        'date' => array('name' => 'date', 'format' => 'Y-m-d', 'formatter' => 'date'),
        'binary' => array('name' => 'blob'),
        'boolean' => array('name' => 'boolean')
    );
/**
 * Connects to the database using config['database'] as a filename.
 *
 * @param array $config Configuration array for connecting
 * @return mixed
 */
    function connect() {
        $config = $this->config;
        $this->connection = $config['connect']($config['database']);
        $this->connected = is_resource($this->connection);

        if ($this->connected) {
            $this->_execute('PRAGMA count_changes = 1;');
        }
        return $this->connected;
    }
/**
 * Disconnects from database.
 *
 * @return boolean True if the database could be disconnected, else false
 */
    function disconnect() {
        @sqlite_close($this->connection);
        $this->connected = false;
        return $this->connected;
    }
/**
 * Executes given SQL statement.
 *
 * @param string $sql SQL statement
 * @return resource Result resource identifier
 */
    function _execute($sql) {
        $result = sqlite_query($this->connection, $sql);

        if (preg_match('/^(INSERT|UPDATE|DELETE)/', $sql)) {
            $this->resultSet($result);
            list($this->_queryStats) = $this->fetchResult();
        }
        return $result;
    }
/**
 * Overrides DboSource::execute() to correctly handle query statistics
 *
 * @param string $sql
 * @return unknown
 */
    function execute($sql) {
        $result = parent::execute($sql);
        $this->_queryStats = array();
        return $result;
    }
/**
 * Returns an array of tables in the database. If there are no tables, an error is raised and the application exits.
 *
 * @return array Array of tablenames in the database
 */
    function listSources() {
        $cache = parent::listSources();

        if ($cache != null) {
            return $cache;
        }
        $result = $this->fetchAll("SELECT name FROM sqlite_master WHERE type='table' ORDER BY name;", false);

        if (empty($result)) {
            return array();
        } else {
            $tables = array();
            foreach ($result as $table) {
                $tables[] = $table[0]['name'];
            }
            parent::listSources($tables);
            return $tables;
        }
        return array();
    }
/**
 * Returns an array of the fields in given table name.
 *
 * @param string $tableName Name of database table to inspect
 * @return array Fields in table. Keys are name and type
 */
    function describe(&$model) {
        $cache = parent::describe($model);
        if ($cache != null) {
            return $cache;
        }
        $fields = array();
        $result = $this->fetchAll('PRAGMA table_info(' . $this->fullTableName($model) . ')');

        foreach ($result as $column) {
            $fields[$column[0]['name']] = array(
                'type' => $this->column($column[0]['type']),
                'null' => !$column[0]['notnull'],
                'default' => $column[0]['dflt_value'],
                'length' => $this->length($column[0]['type'])
            );
            if ($column[0]['pk'] == 1) {
                $colLength = $this->length($column[0]['type']);
                $fields[$column[0]['name']] = array(
                    'type' => $fields[$column[0]['name']]['type'],
                    'null' => false,
                    'default' => $column[0]['dflt_value'],
                    'key' => $this->index['PRI'],
                    'length'=> ($colLength != null) ? $colLength : 11
                );
            }
        }

        $this->__cacheDescription($model->tablePrefix . $model->table, $fields);
        return $fields;
    }
/**
 * Returns a quoted and escaped string of $data for use in an SQL statement.
 *
 * @param string $data String to be prepared for use in an SQL statement
 * @return string Quoted and escaped
 */
    function value($data, $column = null, $safe = false) {
        $parent = parent::value($data, $column, $safe);

        if ($parent != null) {
            return $parent;
        }
        if ($data === null) {
            return 'NULL';
        }
        if ($data === '' && $column !== 'integer' && $column !== 'float' && $column !== 'boolean') {
            return  "''";
        }
        switch ($column) {
            case 'boolean':
                $data = $this->boolean((bool)$data);
            break;
            case 'integer':
            case 'float':
                if ($data === '') {
                    return 'NULL';
                }
            default:
                $data = sqlite_escape_string($data);
            break;
        }
        return "'" . $data . "'";
    }
/**
 * Generates and executes an SQL UPDATE statement for given model, fields, and values.
 *
 * @param Model $model
 * @param array $fields
 * @param array $values
 * @param mixed $conditions
 * @return array
 */
    function update(&$model, $fields = array(), $values = null, $conditions = null) {
        if (empty($values) && !empty($fields)) {
            foreach ($fields as $field => $value) {
                if (strpos($field, $model->alias . '.') !== false) {
                    unset($fields[$field]);
                    $field = str_replace($model->alias . '.', "", $field);
                    $field = str_replace($model->alias . '.', "", $field);
                    $fields[$field] = $value;
                }
            }
        }
        $result = parent::update($model, $fields, $values, $conditions);
        return $result;
    }
/**
 * Deletes all the records in a table and resets the count of the auto-incrementing
 * primary key, where applicable.
 *
 * @param mixed $table A string or model class representing the table to be truncated
 * @return boolean  SQL TRUNCATE TABLE statement, false if not applicable.
 * @access public
 */
    function truncate($table) {
        return $this->execute('DELETE From ' . $this->fullTableName($table));
    }
/**
 * Returns a formatted error message from previous database operation.
 *
 * @return string Error message
 */
    function lastError() {
        $error = sqlite_last_error($this->connection);
        if ($error) {
            return $error.': '.sqlite_error_string($error);
        }
        return null;
    }
/**
 * Returns number of affected rows in previous database operation. If no previous operation exists, this returns false.
 *
 * @return integer Number of affected rows
 */
    function lastAffected() {
        if (!empty($this->_queryStats)) {
            foreach (array('rows inserted', 'rows updated', 'rows deleted') as $key) {
                if (array_key_exists($key, $this->_queryStats)) {
                    return $this->_queryStats[$key];
                }
            }
        }
        return false;
    }
/**
 * Returns number of rows in previous resultset. If no previous resultset exists,
 * this returns false.
 *
 * @return integer Number of rows in resultset
 */
    function lastNumRows() {
        if ($this->hasResult()) {
            sqlite_num_rows($this->_result);
        }
        return false;
    }
/**
 * Returns the ID generated from the previous INSERT operation.
 *
 * @return int
 */
    function lastInsertId() {
        return sqlite_last_insert_rowid($this->connection);
    }
/**
 * Converts database-layer column types to basic types
 *
 * @param string $real Real database-layer column type (i.e. "varchar(255)")
 * @return string Abstract column type (i.e. "string")
 */
    function column($real) {
        if (is_array($real)) {
            $col = $real['name'];
            if (isset($real['limit'])) {
                $col .= '('.$real['limit'].')';
            }
            return $col;
        }

        $col = strtolower(str_replace(')', '', $real));
        $limit = null;
        if (strpos($col, '(') !== false) {
            list($col, $limit) = explode('(', $col);
        }

        if (in_array($col, array('text', 'integer', 'float', 'boolean', 'timestamp', 'date', 'datetime', 'time'))) {
            return $col;
        }
        if (strpos($col, 'varchar') !== false) {
            return 'string';
        }
        if (in_array($col, array('blob', 'clob'))) {
            return 'binary';
        }
        if (strpos($col, 'numeric') !== false) {
            return 'float';
        }
        return 'text';
    }
/**
 * Enter description here...
 *
 * @param unknown_type $results
 */
    function resultSet(&$results) {
        $this->results =& $results;
        $this->map = array();
        $fieldCount = sqlite_num_fields($results);
        $index = $j = 0;

        while ($j < $fieldCount) {
            $columnName = str_replace('"', '', sqlite_field_name($results, $j));

            if (strpos($columnName, '.')) {
                $parts = explode('.', $columnName);
                $this->map[$index++] = array($parts[0], $parts[1]);
            } else {
                $this->map[$index++] = array(0, $columnName);
            }
            $j++;
        }
    }
/**
 * Fetches the next row from the current result set
 *
 * @return unknown
 */
    function fetchResult() {
        if ($row = sqlite_fetch_array($this->results, SQLITE_ASSOC)) {
            $resultRow = array();
            $i = 0;

            foreach ($row as $index => $field) {
                if (strpos($index, '.')) {
                    list($table, $column) = explode('.', str_replace('"', '', $index));
                    $resultRow[$table][$column] = $row[$index];
                } else {
                    $resultRow[0][str_replace('"', '', $index)] = $row[$index];
                }
                $i++;
            }
            return $resultRow;
        } else {
            return false;
        }
    }
/**
 * Returns a limit statement in the correct format for the particular database.
 *
 * @param integer $limit Limit of results returned
 * @param integer $offset Offset from which to start results
 * @return string SQL limit/offset statement
 */
    function limit($limit, $offset = null) {
        if ($limit) {
            $rt = '';
            if (!strpos(strtolower($limit), 'limit') || strpos(strtolower($limit), 'limit') === 0) {
                $rt = ' LIMIT';
            }
            $rt .= ' ' . $limit;
            if ($offset) {
                $rt .= ' OFFSET ' . $offset;
            }
            return $rt;
        }
        return null;
    }
/**
 * Generate a database-native column schema string
 *
 * @param array $column An array structured like the following: array('name'=>'value', 'type'=>'value'[, options]),
 *                      where options can be 'default', 'length', or 'key'.
 * @return string
 */
    function buildColumn($column) {
        $name = $type = null;
        $column = array_merge(array('null' => true), $column);
        extract($column);

        if (empty($name) || empty($type)) {
            trigger_error('Column name or type not defined in schema', E_USER_WARNING);
            return null;
        }

        if (!isset($this->columns[$type])) {
            trigger_error("Column type {$type} does not exist", E_USER_WARNING);
            return null;
        }

        $real = $this->columns[$type];
        $out = $this->name($name) . ' ' . $real['name'];
        if (isset($column['key']) && $column['key'] == 'primary' && $type == 'integer') {
            return $this->name($name) . ' ' . $this->columns['primary_key']['name'];
        }
        if (isset($real['limit']) || isset($real['length']) || isset($column['limit']) || isset($column['length'])) {
            if (isset($column['length'])) {
                $length = $column['length'];
            } elseif (isset($column['limit'])) {
                $length = $column['limit'];
            } elseif (isset($real['length'])) {
                $length = $real['length'];
            } else {
                $length = $real['limit'];
            }
            $out .= '(' . $length . ')';
        }
        if (isset($column['key']) && $column['key'] == 'primary' && $type == 'integer') {
            $out .= ' ' . $this->columns['primary_key']['name'];
        } elseif (isset($column['key']) && $column['key'] == 'primary') {
            $out .= ' NOT NULL';
        } elseif (isset($column['default']) && isset($column['null']) && $column['null'] == false) {
            $out .= ' DEFAULT ' . $this->value($column['default'], $type) . ' NOT NULL';
        } elseif (isset($column['default'])) {
            $out .= ' DEFAULT ' . $this->value($column['default'], $type);
        } elseif (isset($column['null']) && $column['null'] == true) {
            $out .= ' DEFAULT NULL';
        } elseif (isset($column['null']) && $column['null'] == false) {
            $out .= ' NOT NULL';
        }
        return $out;
    }
/**
 * Sets the database encoding
 *
 * @param string $enc Database encoding
 */
    function setEncoding($enc) {
        if (!in_array($enc, array("UTF-8", "UTF-16", "UTF-16le", "UTF-16be"))) {
            return false;
        }
        return $this->_execute("PRAGMA encoding = \"{$enc}\"") !== false;
    }
/**
 * Gets the database encoding
 *
 * @return string The database encoding
 */
    function getEncoding() {
        return $this->fetchRow('PRAGMA encoding');
    }
/**
 * Removes redundant primary key indexes, as they are handled in the column def of the key.
 *
 * @param array $indexes
 * @param string $table
 * @return string
 */
    function buildIndex($indexes, $table = null) {
        $join = array();

        foreach ($indexes as $name => $value) {

            if ($name == 'PRIMARY') {
                continue;
            }
            $out = 'CREATE ';

            if (!empty($value['unique'])) {
                $out .= 'UNIQUE ';
            }
            if (is_array($value['column'])) {
                $value['column'] = join(', ', array_map(array(&$this, 'name'), $value['column']));
            } else {
                $value['column'] = $this->name($value['column']);
            }
            $out .= "INDEX {$name} ON {$table}({$value['column']});";
            $join[] = $out;
        }
        return $join;
    }
/**
 * Overrides DboSource::index to handle SQLite indexe introspection
 * 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);
        if ($table) {
            $indexes = $this->query('PRAGMA index_list(' . $table . ')');
            $tableInfo = $this->query('PRAGMA table_info(' . $table . ')');
            foreach ($indexes as $i => $info) {
                $key = array_pop($info);
                $keyInfo = $this->query('PRAGMA index_info("' . $key['name'] . '")');
                foreach ($keyInfo as $keyCol) {
                    if (!isset($index[$key['name']])) {
                        $col = array();
                        if (preg_match('/autoindex/', $key['name'])) {
                            $key['name'] = 'PRIMARY';
                        }
                        $index[$key['name']]['column'] = $keyCol[0]['name'];
                        $index[$key['name']]['unique'] = intval($key['unique'] == 1);
                    } else {
                        if (!is_array($index[$key['name']]['column'])) {
                            $col[] = $index[$key['name']]['column'];
                        }
                        $col[] = $keyCol[0]['name'];
                        $index[$key['name']]['column'] = $col;
                    }
                }
            }
        }
        return $index;
    }
    
/**
 * Overrides DboSource::renderStatement to handle schema generation with SQLite-style indexes
 *
 * @param string $type
 * @param array $data
 * @return string
 */
    function renderStatement($type, $data) {
        switch (strtolower($type)) {
            case 'schema':
                extract($data);

                foreach (array('columns', 'indexes') as $var) {
                    if (is_array(${$var})) {
                        ${$var} = "\t" . join(",\n\t", array_filter(${$var}));
                    }
                }
                return "CREATE TABLE {$table} (\n{$columns});\n{$indexes}";
            break;
            default:
                return parent::renderStatement($type, $data);
            break;
        }
    }
}
?>

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