Modules

abstract Database
extends Kohana_Database

Database connection wrapper/helper.

You may get a database instance using Database::instance('name') where name is the config group.

This class provides connection instance management via Database Drivers, as well as quoting, escaping and other related functions. Querys are done using Database_Query and Database_Query_Builder objects, which can be easily created using the DB helper class.

package
Kohana/Database
category
Base
author
Kohana Team
copyright
© 2008-2012 Kohana Team
license
http://kohanaphp.com/license

Class declared in MODPATH/database/classes/Database.php on line 3.

Constants

SELECT

integer 1

INSERT

integer 2

UPDATE

integer 3

DELETE

integer 4

Properties

public static string $default

default instance name

string(7) "default"

public static array $instances

Database instances

array(0) 

public string $last_query

the last query executed

Default value:
NULL

protected $_config

Default value:
NULL

protected $_connection

Default value:
NULL

protected $_identifier

Default value:
string(1) """

protected $_instance

Default value:
NULL

Methods

public __construct( ) (defined in Kohana_Database)

Stores the database configuration locally and name the instance.

This method cannot be accessed directly, you must use Database::instance.

Return Values

  • void

Source Code

public function __construct($name, array $config)
{
    // Set the instance name
    $this->_instance = $name;
 
    // Store the config locally
    $this->_config = $config;
 
    if (empty($this->_config['table_prefix']))
    {
        $this->_config['table_prefix'] = '';
    }
}

public __destruct( ) (defined in Kohana_Database)

Disconnect from the database when the object is destroyed.

// Destroy the database instance
unset(Database::instances[(string) $db], $db);

Calling unset($db) is not enough to destroy the database, as it will still be stored in Database::$instances.

Return Values

  • void

Source Code

public function __destruct()
{
    $this->disconnect();
}

public __toString( ) (defined in Kohana_Database)

Returns the database instance name.

echo (string) $db;

Return Values

  • string

Source Code

public function __toString()
{
    return $this->_instance;
}

abstract public begin( [ string $mode = NULL ] ) (defined in Kohana_Database)

Start a SQL transaction

// Start the transactions
$db->begin();
 
try {
     DB::insert('users')->values($user1)...
     DB::insert('users')->values($user2)...
     // Insert successful commit the changes
     $db->commit();
}
catch (Database_Exception $e)
{
     // Insert failed. Rolling back changes...
     $db->rollback();
 }

Parameters

  • string $mode = NULL - Transaction mode

Return Values

  • boolean

Source Code

abstract public function begin($mode = NULL);

abstract public commit( ) (defined in Kohana_Database)

Commit the current transaction

// Commit the database changes
$db->commit();

Return Values

  • boolean

Source Code

abstract public function commit();

abstract public connect( ) (defined in Kohana_Database)

Connect to the database. This is called automatically when the first query is executed.

$db->connect();

Tags

Return Values

  • void

Source Code

abstract public function connect();

public count_records( mixed $table ) (defined in Kohana_Database)

Count the number of records in a table.

// Get the total number of records in the "users" table
$count = $db->count_records('users');

Parameters

  • mixed $table required - Table name string or array(query, alias)

Return Values

  • integer

Source Code

public function count_records($table)
{
    // Quote the table name
    $table = $this->quote_table($table);
 
    return $this->query(Database::SELECT, 'SELECT COUNT(*) AS total_row_count FROM '.$table, FALSE)
        ->get('total_row_count');
}

public datatype( string $type ) (defined in Kohana_Database)

Returns a normalized array describing the SQL data type

$db->datatype('char');

Parameters

  • string $type required - SQL data type

Return Values

  • array

Source Code

public function datatype($type)
{
    static $types = array
    (
        // SQL-92
        'bit'                           => array('type' => 'string', 'exact' => TRUE),
        'bit varying'                   => array('type' => 'string'),
        'char'                          => array('type' => 'string', 'exact' => TRUE),
        'char varying'                  => array('type' => 'string'),
        'character'                     => array('type' => 'string', 'exact' => TRUE),
        'character varying'             => array('type' => 'string'),
        'date'                          => array('type' => 'string'),
        'dec'                           => array('type' => 'float', 'exact' => TRUE),
        'decimal'                       => array('type' => 'float', 'exact' => TRUE),
        'double precision'              => array('type' => 'float'),
        'float'                         => array('type' => 'float'),
        'int'                           => array('type' => 'int', 'min' => '-2147483648', 'max' => '2147483647'),
        'integer'                       => array('type' => 'int', 'min' => '-2147483648', 'max' => '2147483647'),
        'interval'                      => array('type' => 'string'),
        'national char'                 => array('type' => 'string', 'exact' => TRUE),
        'national char varying'         => array('type' => 'string'),
        'national character'            => array('type' => 'string', 'exact' => TRUE),
        'national character varying'    => array('type' => 'string'),
        'nchar'                         => array('type' => 'string', 'exact' => TRUE),
        'nchar varying'                 => array('type' => 'string'),
        'numeric'                       => array('type' => 'float', 'exact' => TRUE),
        'real'                          => array('type' => 'float'),
        'smallint'                      => array('type' => 'int', 'min' => '-32768', 'max' => '32767'),
        'time'                          => array('type' => 'string'),
        'time with time zone'           => array('type' => 'string'),
        'timestamp'                     => array('type' => 'string'),
        'timestamp with time zone'      => array('type' => 'string'),
        'varchar'                       => array('type' => 'string'),
 
        // SQL:1999
        'binary large object'               => array('type' => 'string', 'binary' => TRUE),
        'blob'                              => array('type' => 'string', 'binary' => TRUE),
        'boolean'                           => array('type' => 'bool'),
        'char large object'                 => array('type' => 'string'),
        'character large object'            => array('type' => 'string'),
        'clob'                              => array('type' => 'string'),
        'national character large object'   => array('type' => 'string'),
        'nchar large object'                => array('type' => 'string'),
        'nclob'                             => array('type' => 'string'),
        'time without time zone'            => array('type' => 'string'),
        'timestamp without time zone'       => array('type' => 'string'),
 
        // SQL:2003
        'bigint'    => array('type' => 'int', 'min' => '-9223372036854775808', 'max' => '9223372036854775807'),
 
        // SQL:2008
        'binary'            => array('type' => 'string', 'binary' => TRUE, 'exact' => TRUE),
        'binary varying'    => array('type' => 'string', 'binary' => TRUE),
        'varbinary'         => array('type' => 'string', 'binary' => TRUE),
    );
 
    if (isset($types[$type]))
        return $types[$type];
 
    return array();
}

public disconnect( ) (defined in Kohana_Database)

Disconnect from the database. This is called automatically by Database::__destruct. Clears the database instance from Database::$instances.

$db->disconnect();

Return Values

  • boolean

Source Code

public function disconnect()
{
    unset(Database::$instances[$this->_instance]);
 
    return TRUE;
}

abstract public escape( string $value ) (defined in Kohana_Database)

Sanitize a string by escaping characters that could cause an SQL injection attack.

$value = $db->escape('any string');

Parameters

  • string $value required - Value to quote

Return Values

  • string

Source Code

abstract public function escape($value);

public static instance( [ string $name = NULL , array $config = NULL ] ) (defined in Kohana_Database)

Get a singleton Database instance. If configuration is not specified, it will be loaded from the database configuration file using the same group as the name.

// Load the default database
$db = Database::instance();
 
// Create a custom configured instance
$db = Database::instance('custom', $config);

Parameters

  • string $name = NULL - Instance name
  • array $config = NULL - Configuration parameters

Return Values

  • Database

Source Code

public static function instance($name = NULL, array $config = NULL)
{
    if ($name === NULL)
    {
        // Use the default instance name
        $name = Database::$default;
    }
 
    if ( ! isset(Database::$instances[$name]))
    {
        if ($config === NULL)
        {
            // Load the configuration for this database
            $config = Kohana::$config->load('database')->$name;
        }
 
        if ( ! isset($config['type']))
        {
            throw new Kohana_Exception('Database type not defined in :name configuration',
                array(':name' => $name));
        }
 
        // Set the driver class name
        $driver = 'Database_'.ucfirst($config['type']);
 
        // Create the database connection instance
        $driver = new $driver($name, $config);
 
        // Store the database instance
        Database::$instances[$name] = $driver;
    }
 
    return Database::$instances[$name];
}

abstract public list_columns( string $table [, string $like = NULL , boolean $add_prefix = bool TRUE ] ) (defined in Kohana_Database)

Lists all of the columns in a table. Optionally, a LIKE string can be used to search for specific fields.

// Get all columns from the "users" table
$columns = $db->list_columns('users');
 
// Get all name-related columns
$columns = $db->list_columns('users', '%name%');
 
// Get the columns from a table that doesn't use the table prefix
$columns = $db->list_columns('users', NULL, FALSE);

Parameters

  • string $table required - Table to get columns from
  • string $like = NULL - Column to search for
  • boolean $add_prefix = bool TRUE - Whether to add the table prefix automatically or not

Return Values

  • array

Source Code

abstract public function list_columns($table, $like = NULL, $add_prefix = TRUE);

abstract public list_tables( [ string $like = NULL ] ) (defined in Kohana_Database)

List all of the tables in the database. Optionally, a LIKE string can be used to search for specific tables.

// Get all tables in the current database
$tables = $db->list_tables();
 
// Get all user-related tables
$tables = $db->list_tables('user%');

Parameters

  • string $like = NULL - Table to search for

Return Values

  • array

Source Code

abstract public function list_tables($like = NULL);

abstract public query( integer $type , string $sql [, mixed $as_object = bool FALSE , array $params = NULL ] ) (defined in Kohana_Database)

Perform an SQL query of the given type.

// Make a SELECT query and use objects for results
$db->query(Database::SELECT, 'SELECT * FROM groups', TRUE);
 
// Make a SELECT query and use "Model_User" for the results
$db->query(Database::SELECT, 'SELECT * FROM users LIMIT 1', 'Model_User');

Parameters

  • integer $type required - Database::SELECT, Database::INSERT, etc
  • string $sql required - SQL query
  • mixed $as_object = bool FALSE - Result object class string, TRUE for stdClass, FALSE for assoc array
  • array $params = NULL - Object construct parameters for result class

Return Values

  • object - Database_Result for SELECT queries
  • array - List (insert id, row count) for INSERT queries
  • integer - Number of affected rows for all other queries

Source Code

abstract public function query($type, $sql, $as_object = FALSE, array $params = NULL);

public quote( mixed $value ) (defined in Kohana_Database)

Quote a value for an SQL query.

$db->quote(NULL);   // 'NULL'
$db->quote(10);     // 10
$db->quote('fred'); // 'fred'

Objects passed to this function will be converted to strings. Database_Expression objects will be compiled. Database_Query objects will be compiled and converted to a sub-query. All other objects will be converted using the __toString method.

Parameters

  • mixed $value required - Any value to quote

Tags

Return Values

  • string

Source Code

public function quote($value)
{
    if ($value === NULL)
    {
        return 'NULL';
    }
    elseif ($value === TRUE)
    {
        return "'1'";
    }
    elseif ($value === FALSE)
    {
        return "'0'";
    }
    elseif (is_object($value))
    {
        if ($value instanceof Database_Query)
        {
            // Create a sub-query
            return '('.$value->compile($this).')';
        }
        elseif ($value instanceof Database_Expression)
        {
            // Compile the expression
            return $value->compile($this);
        }
        else
        {
            // Convert the object to a string
            return $this->quote( (string) $value);
        }
    }
    elseif (is_array($value))
    {
        return '('.implode(', ', array_map(array($this, __FUNCTION__), $value)).')';
    }
    elseif (is_int($value))
    {
        return (int) $value;
    }
    elseif (is_float($value))
    {
        // Convert to non-locale aware float to prevent possible commas
        return sprintf('%F', $value);
    }
 
    return $this->escape($value);
}

public quote_column( mixed $column ) (defined in Kohana_Database)

Quote a database column name and add the table prefix if needed.

$column = $db->quote_column($column);

You can also use SQL methods within identifiers.

$column = $db->quote_column(DB::expr('COUNT(`column`)'));

Objects passed to this function will be converted to strings. Database_Expression objects will be compiled. Database_Query objects will be compiled and converted to a sub-query. All other objects will be converted using the __toString method.

Parameters

  • mixed $column required - Column name or array(column, alias)

Tags

Return Values

  • string

Source Code

public function quote_column($column)
{
    // Identifiers are escaped by repeating them
    $escaped_identifier = $this->_identifier.$this->_identifier;
 
    if (is_array($column))
    {
        list($column, $alias) = $column;
        $alias = str_replace($this->_identifier, $escaped_identifier, $alias);
    }
 
    if ($column instanceof Database_Query)
    {
        // Create a sub-query
        $column = '('.$column->compile($this).')';
    }
    elseif ($column instanceof Database_Expression)
    {
        // Compile the expression
        $column = $column->compile($this);
    }
    else
    {
        // Convert to a string
        $column = (string) $column;
 
        $column = str_replace($this->_identifier, $escaped_identifier, $column);
 
        if ($column === '*')
        {
            return $column;
        }
        elseif (strpos($column, '.') !== FALSE)
        {
            $parts = explode('.', $column);
 
            if ($prefix = $this->table_prefix())
            {
                // Get the offset of the table name, 2nd-to-last part
                $offset = count($parts) - 2;
 
                // Add the table prefix to the table name
                $parts[$offset] = $prefix.$parts[$offset];
            }
 
            foreach ($parts as & $part)
            {
                if ($part !== '*')
                {
                    // Quote each of the parts
                    $part = $this->_identifier.$part.$this->_identifier;
                }
            }
 
            $column = implode('.', $parts);
        }
        else
        {
            $column = $this->_identifier.$column.$this->_identifier;
        }
    }
 
    if (isset($alias))
    {
        $column .= ' AS '.$this->_identifier.$alias.$this->_identifier;
    }
 
    return $column;
}

public quote_identifier( mixed $value ) (defined in Kohana_Database)

Quote a database identifier

Objects passed to this function will be converted to strings. Database_Expression objects will be compiled. Database_Query objects will be compiled and converted to a sub-query. All other objects will be converted using the __toString method.

Parameters

  • mixed $value required - Any identifier

Return Values

  • string

Source Code

public function quote_identifier($value)
{
    // Identifiers are escaped by repeating them
    $escaped_identifier = $this->_identifier.$this->_identifier;
 
    if (is_array($value))
    {
        list($value, $alias) = $value;
        $alias = str_replace($this->_identifier, $escaped_identifier, $alias);
    }
 
    if ($value instanceof Database_Query)
    {
        // Create a sub-query
        $value = '('.$value->compile($this).')';
    }
    elseif ($value instanceof Database_Expression)
    {
        // Compile the expression
        $value = $value->compile($this);
    }
    else
    {
        // Convert to a string
        $value = (string) $value;
 
        $value = str_replace($this->_identifier, $escaped_identifier, $value);
 
        if (strpos($value, '.') !== FALSE)
        {
            $parts = explode('.', $value);
 
            foreach ($parts as & $part)
            {
                // Quote each of the parts
                $part = $this->_identifier.$part.$this->_identifier;
            }
 
            $value = implode('.', $parts);
        }
        else
        {
            $value = $this->_identifier.$value.$this->_identifier;
        }
    }
 
    if (isset($alias))
    {
        $value .= ' AS '.$this->_identifier.$alias.$this->_identifier;
    }
 
    return $value;
}

public quote_table( mixed $table ) (defined in Kohana_Database)

Quote a database table name and adds the table prefix if needed.

$table = $db->quote_table($table);

Objects passed to this function will be converted to strings. Database_Expression objects will be compiled. Database_Query objects will be compiled and converted to a sub-query. All other objects will be converted using the __toString method.

Parameters

  • mixed $table required - Table name or array(table, alias)

Tags

Return Values

  • string

Source Code

public function quote_table($table)
{
    // Identifiers are escaped by repeating them
    $escaped_identifier = $this->_identifier.$this->_identifier;
 
    if (is_array($table))
    {
        list($table, $alias) = $table;
        $alias = str_replace($this->_identifier, $escaped_identifier, $alias);
    }
 
    if ($table instanceof Database_Query)
    {
        // Create a sub-query
        $table = '('.$table->compile($this).')';
    }
    elseif ($table instanceof Database_Expression)
    {
        // Compile the expression
        $table = $table->compile($this);
    }
    else
    {
        // Convert to a string
        $table = (string) $table;
 
        $table = str_replace($this->_identifier, $escaped_identifier, $table);
 
        if (strpos($table, '.') !== FALSE)
        {
            $parts = explode('.', $table);
 
            if ($prefix = $this->table_prefix())
            {
                // Get the offset of the table name, last part
                $offset = count($parts) - 1;
 
                // Add the table prefix to the table name
                $parts[$offset] = $prefix.$parts[$offset];
            }
 
            foreach ($parts as & $part)
            {
                // Quote each of the parts
                $part = $this->_identifier.$part.$this->_identifier;
            }
 
            $table = implode('.', $parts);
        }
        else
        {
            // Add the table prefix
            $table = $this->_identifier.$this->table_prefix().$table.$this->_identifier;
        }
    }
 
    if (isset($alias))
    {
        // Attach table prefix to alias
        $table .= ' AS '.$this->_identifier.$this->table_prefix().$alias.$this->_identifier;
    }
 
    return $table;
}

abstract public rollback( ) (defined in Kohana_Database)

Abort the current transaction

// Undo the changes
$db->rollback();

Return Values

  • boolean

Source Code

abstract public function rollback();

abstract public set_charset( string $charset ) (defined in Kohana_Database)

Set the connection character set. This is called automatically by Database::connect.

$db->set_charset('utf8');

Parameters

  • string $charset required - Character set name

Tags

Return Values

  • void

Source Code

abstract public function set_charset($charset);

public table_prefix( ) (defined in Kohana_Database)

Return the table prefix defined in the current configuration.

$prefix = $db->table_prefix();

Return Values

  • string

Source Code

public function table_prefix()
{
    return $this->_config['table_prefix'];
}

protected _parse_type( string $type ) (defined in Kohana_Database)

Extracts the text between parentheses, if any.

// Returns: array('CHAR', '6')
list($type, $length) = $db->_parse_type('CHAR(6)');

Parameters

  • string $type required - $type

Return Values

  • array - List containing the type and length, if any

Source Code

protected function _parse_type($type)
{
    if (($open = strpos($type, '(')) === FALSE)
    {
        // No length specified
        return array($type, NULL);
    }
 
    // Closing parenthesis
    $close = strrpos($type, ')', $open);
 
    // Length without parentheses
    $length = substr($type, $open + 1, $close - 1 - $open);
 
    // Type without the length
    $type = substr($type, 0, $open).substr($type, $close + 1);
 
    return array($type, $length);
}