O Guia Definitivo do Yii 1.1

ALTER TABLE `tbl_profile` ADD CONSTRAINT `fk_profile_user_id`
// FOREIGN KEY (`user_id`) REFERENCES `tbl_user` (`id`)
// ON DELETE CASCADE ON UPDATE CASCADE
addForeignKey('fk_profile_user_id', 'tbl_profile', 'user_id',
'tbl_user', 'id', 'CASCADE', 'CASCADE')
dropForeignKey
function dropForeignKey($name, $table)
The dropForeignKey method builds and executes a SQL statement for dropping a foreign
key constraint. The $name parameter specifies the name of the foreign key constraint to
be dropped. The $table parameter specifies the name of the table that the foreign key is
on. The query builder will quote the table name as well as the constraint names properly.
Below is an example showing how to drop a foreign key constraint:
// ALTER TABLE `tbl_profile` DROP FOREIGN KEY `fk_profile_user_id`
dropForeignKey('fk_profile_user_id', 'tbl_profile')
createIndex
function createIndex($name, $table, $column, $unique=false)
The createIndex method builds and executes a SQL statement for creating an index. The
$name parameter specifies the name of the index to be created. The $table parameter
specifies the name of the table that the index is on. The $column parameter specifies the
name of the column to be indexed. And the $unique parameter specifies whether a unique
index should be created. If the index consists of multiple columns, they must be separated
by commas. The query builder will properly quote the table name, index name and column
name(s).
Below is an example showing how to create an index:
// CREATE INDEX `idx_username` ON `tbl_user` (`username`)
createIndex('idx_username', 'tbl_user')
dropIndex
function dropIndex($name, $table)
The dropIndex method builds and executes a SQL statement for dropping an index. The
$name parameter specifies the name of the index to be dropped. The $table parameter
specifies the name of the table that the index is on. The query builder will quote the table
name as well as the index names properly.