<?php
/**
* CDbMigration class file.
*
* @author Qiang Xue <[email protected]>
* @link http://www.yiiframework.com/
* @copyright Copyright © 2008-2011 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
/**
* CDbMigration is the base class for representing a database migration.
*
* CDbMigration is designed to be used together with the "yiic migrate" command.
*
* Each child class of CDbMigration represents an individual database migration which
* is identified by the child class name.
*
* Within each migration, the {@link up} method contains the logic for "upgrading"
* the database used in an application; while the {@link down} method contains "downgrading"
* logic. The "yiic migrate" command manages all available migrations in an application.
*
* CDbMigration provides a set of convenient methods for manipulating database data and schema.
* For example, the {@link insert} method can be used to easily insert a row of data into
* a database table; the {@link createTable} method can be used to create a database table.
* Compared with the same methods in {@link CDbCommand}, these methods will display extra
* information showing the method parameters and execution time, which may be useful when
* applying migrations.
*
* @property CDbConnection $dbConnection The currently active database connection.
*
* @author Qiang Xue <[email protected]>
* @package system.db
* @since 1.1.6
*/
abstract class CDbMigration extends CComponent
{
private $_db;
/**
* This method contains the logic to be executed when applying this migration.
* Child classes may implement this method to provide actual migration logic.
* @return boolean
*/
public function up()
{
$transaction=$this->getDbConnection()->beginTransaction();
try
{
if($this->safeUp()===false)
{
$transaction->rollback();
return false;
}
$transaction->commit();
}
catch(Exception $e)
{
echo "Exception: ".$e->getMessage().' ('.$e->getFile().':'.$e->getLine().")\n";
echo $e->getTraceAsString()."\n";
$transaction->rollback();
return false;
}
}
/**
* This method contains the logic to be executed when removing this migration.
* The default implementation throws an exception indicating the migration cannot be removed.
* Child classes may override this method if the corresponding migrations can be removed.
* @return boolean
*/
public function down()
{
$transaction=$this->getDbConnection()->beginTransaction();
try
{
if($this->safeDown()===false)
{
$transaction->rollback();
return false;
}
$transaction->commit();
}
catch(Exception $e)
{
echo "Exception: ".$e->getMessage().' ('.$e->getFile().':'.$e->getLine().")\n";
echo $e->getTraceAsString()."\n";
$transaction->rollback();
return false;
}
}
/**
* This method contains the logic to be executed when applying this migration.
* This method differs from {@link up} in that the DB logic implemented here will
* be enclosed within a DB transaction.
* Child classes may implement this method instead of {@link up} if the DB logic
* needs to be within a transaction.
* @return boolean
* @since 1.1.7
*/
public function safeUp()
{
}
/**
* This method contains the logic to be executed when removing this migration.
* This method differs from {@link down} in that the DB logic implemented here will
* be enclosed within a DB transaction.
* Child classes may implement this method instead of {@link up} if the DB logic
* needs to be within a transaction.
* @return boolean
* @since 1.1.7
*/
public function safeDown()
{
}
/**
* Returns the currently active database connection.
* By default, the 'db' application component will be returned and activated.
* You can call {@link setDbConnection} to switch to a different database connection.
* Methods such as {@link insert}, {@link createTable} will use this database connection
* to perform DB queries.
* @return CDbConnection the currently active database connection
*/
public function getDbConnection()
{
if($this->_db===null)
{
$this->_db=Yii::app()->getComponent('db');
if(!$this->_db instanceof CDbConnection)
throw new CException(Yii::t('yii', 'The "db" application component must be configured to be a CDbConnection object.'));
}
return $this->_db;
}
/**
* Sets the currently active database connection.
* The database connection will be used by the methods such as {@link insert}, {@link createTable}.
* @param CDbConnection $db the database connection component
*/
public function setDbConnection($db)
{
$this->_db=$db;
}
/**
* Executes a SQL statement.
* This method executes the specified SQL statement using {@link dbConnection}.
* @param string $sql the SQL statement to be executed
* @param array $params input parameters (name=>value) for the SQL execution. See {@link CDbCommand::execute} for more details.
* @since 1.1.7
*/
public function execute($sql, $params=array())
{
echo " > execute SQL: $sql ...";
$time=microtime(true);
$this->getDbConnection()->createCommand($sql)->execute($params);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Creates and executes an INSERT SQL statement.
* The method will properly escape the column names, and bind the values to be inserted.
* @param string $table the table that new rows will be inserted into.
* @param array $columns the column data (name=>value) to be inserted into the table.
*/
public function insert($table, $columns)
{
echo " > insert into $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->insert($table, $columns);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Creates and executes an UPDATE SQL statement.
* The method will properly escape the column names and bind the values to be updated.
* @param string $table the table to be updated.
* @param array $columns the column data (name=>value) to be updated.
* @param mixed $conditions the conditions that will be put in the WHERE part. Please
* refer to {@link CDbCommand::where} on how to specify conditions.
* @param array $params the parameters to be bound to the query.
*/
public function update($table, $columns, $conditions='', $params=array())
{
echo " > update $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->update($table, $columns, $conditions, $params);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Creates and executes a DELETE SQL statement.
* @param string $table the table where the data will be deleted from.
* @param mixed $conditions the conditions that will be put in the WHERE part. Please
* refer to {@link CDbCommand::where} on how to specify conditions.
* @param array $params the parameters to be bound to the query.
*/
public function delete($table, $conditions='', $params=array())
{
echo " > delete from $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->delete($table, $conditions, $params);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for creating a new DB table.
*
* The columns in the new table should be specified as name-definition pairs (e.g. 'name'=>'string'),
* where name stands for a column name which will be properly quoted by the method, and definition
* stands for the column type which can contain an abstract DB type.
* The {@link getColumnType} method will be invoked to convert any abstract type into a physical one.
*
* If a column is specified with definition only (e.g. 'PRIMARY KEY (name, type)'), it will be directly
* inserted into the generated SQL.
*
* @param string $table the name of the table to be created. The name will be properly quoted by the method.
* @param array $columns the columns (name=>definition) in the new table.
* @param string $options additional SQL fragment that will be appended to the generated SQL.
*/
public function createTable($table, $columns, $options=null)
{
echo " > create table $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->createTable($table, $columns, $options);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for renaming a DB table.
* @param string $table the table to be renamed. The name will be properly quoted by the method.
* @param string $newName the new table name. The name will be properly quoted by the method.
*/
public function renameTable($table, $newName)
{
echo " > rename table $table to $newName ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->renameTable($table, $newName);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for dropping a DB table.
* @param string $table the table to be dropped. The name will be properly quoted by the method.
*/
public function dropTable($table)
{
echo " > drop table $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->dropTable($table);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for truncating a DB table.
* @param string $table the table to be truncated. The name will be properly quoted by the method.
*/
public function truncateTable($table)
{
echo " > truncate table $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->truncateTable($table);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for adding a new DB column.
* @param string $table the table that the new column will be added to. The table name will be properly quoted by the method.
* @param string $column the name of the new column. The name will be properly quoted by the method.
* @param string $type the column type. The {@link getColumnType} method will be invoked to convert abstract column type (if any)
* into the physical one. Anything that is not recognized as abstract type will be kept in the generated SQL.
* For example, 'string' will be turned into 'varchar(255)', while 'string not null' will become 'varchar(255) not null'.
*/
public function addColumn($table, $column, $type)
{
echo " > add column $column $type to table $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->addColumn($table, $column, $type);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for dropping a DB column.
* @param string $table the table whose column is to be dropped. The name will be properly quoted by the method.
* @param string $column the name of the column to be dropped. The name will be properly quoted by the method.
*/
public function dropColumn($table, $column)
{
echo " > drop column $column from table $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->dropColumn($table, $column);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for renaming a column.
* @param string $table the table whose column is to be renamed. The name will be properly quoted by the method.
* @param string $name the old name of the column. The name will be properly quoted by the method.
* @param string $newName the new name of the column. The name will be properly quoted by the method.
*/
public function renameColumn($table, $name, $newName)
{
echo " > rename column $name in table $table to $newName ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->renameColumn($table, $name, $newName);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for changing the definition of a column.
* @param string $table the table whose column is to be changed. The table name will be properly quoted by the method.
* @param string $column the name of the column to be changed. The name will be properly quoted by the method.
* @param string $type the new column type. The {@link getColumnType} method will be invoked to convert abstract column type (if any)
* into the physical one. Anything that is not recognized as abstract type will be kept in the generated SQL.
* For example, 'string' will be turned into 'varchar(255)', while 'string not null' will become 'varchar(255) not null'.
*/
public function alterColumn($table, $column, $type)
{
echo " > alter column $column in table $table to $type ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->alterColumn($table, $column, $type);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds a SQL statement for adding a foreign key constraint to an existing table.
* The method will properly quote the table and column names.
* @param string $name the name of the foreign key constraint.
* @param string $table the table that the foreign key constraint will be added to.
* @param string $columns the name of the column to that the constraint will be added on. If there are multiple columns, separate them with commas.
* @param string $refTable the table that the foreign key references to.
* @param string $refColumns the name of the column that the foreign key references to. If there are multiple columns, separate them with commas.
* @param string $delete the ON DELETE option. Most DBMS support these options: RESTRICT, CASCADE, NO ACTION, SET DEFAULT, SET NULL
* @param string $update the ON UPDATE option. Most DBMS support these options: RESTRICT, CASCADE, NO ACTION, SET DEFAULT, SET NULL
*/
public function addForeignKey($name, $table, $columns, $refTable, $refColumns, $delete=null, $update=null)
{
echo " > add foreign key $name: $table ($columns) references $refTable ($refColumns) ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->addForeignKey($name, $table, $columns, $refTable, $refColumns, $delete, $update);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds a SQL statement for dropping a foreign key constraint.
* @param string $name the name of the foreign key constraint to be dropped. The name will be properly quoted by the method.
* @param string $table the table whose foreign is to be dropped. The name will be properly quoted by the method.
*/
public function dropForeignKey($name, $table)
{
echo " > drop foreign key $name from table $table ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->dropForeignKey($name, $table);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for creating a new index.
* @param string $name the name of the index. The name will be properly quoted by the method.
* @param string $table the table that the new index will be created for. The table name will be properly quoted by the method.
* @param string $column the column(s) that should be included in the index. If there are multiple columns, please separate them
* by commas. The column names will be properly quoted by the method.
* @param boolean $unique whether to add UNIQUE constraint on the created index.
*/
public function createIndex($name, $table, $column, $unique=false)
{
echo " > create".($unique ? ' unique':'')." index $name on $table ($column) ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->createIndex($name, $table, $column, $unique);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for dropping an index.
* @param string $name the name of the index to be dropped. The name will be properly quoted by the method.
* @param string $table the table whose index is to be dropped. The name will be properly quoted by the method.
*/
public function dropIndex($name, $table)
{
echo " > drop index $name ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->dropIndex($name, $table);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Refreshed schema cache for a table
* @param string $table name of the table to refresh
* @since 1.1.9
*/
public function refreshTableSchema($table)
{
echo " > refresh table $table schema cache ...";
$time=microtime(true);
$this->getDbConnection()->getSchema()->getTable($table,true);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for creating a primary key, supports composite primary keys.
* @param string $name name of the primary key constraint to add
* @param string $table name of the table to add primary key to
* @param string $columns name of the column to utilise as primary key. If there are multiple columns, separate them with commas.
* @since 1.1.13
*/
public function addPrimaryKey($name,$table,$columns)
{
echo " > alter table $table add constraint $name primary key ($columns) ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->addPrimaryKey($name,$table,$columns);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
/**
* Builds and executes a SQL statement for removing a primary key, supports composite primary keys.
* @param string $name name of the constraint to remove
* @param string $table name of the table to remove primary key from
* @since 1.1.13
*/
public function dropPrimaryKey($name,$table)
{
echo " > alter table $table drop constraint $name primary key $column ...";
$time=microtime(true);
$this->getDbConnection()->createCommand()->dropPrimaryKey($name,$table);
echo " done (time: ".sprintf('%.3f', microtime(true)-$time)."s)\n";
}
}