Writing Migrations

Phinx relies on migrations in order to transform your database. Each migration is represented by a PHP class in a unique file. It is preferred that you write your migrations using the Phinx PHP API, but raw SQL is also supported.

Creating a New Migration

Let’s start by creating a new Phinx migration. Run Phinx using the create command:

$ php vendor/bin/phinx create MyNewMigration

This will create a new migration in the format YYYYMMDDHHMMSS_my_new_migration.php where the first 14 characters are replaced with the current timestamp down to the second.

Phinx automatically creates a skeleton migration file with a single method:

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Change Method.
     *
     * Write your reversible migrations using this method.
     *
     * More information on writing migrations is available here:
     * http://docs.phinx.org/en/latest/migrations.html#the-abstractmigration-class
     *
     * The following commands can be used in this method and Phinx will
     * automatically reverse them when rolling back:
     *
     *    createTable
     *    renameTable
     *    addColumn
     *    renameColumn
     *    addIndex
     *    addForeignKey
     *
     * Remember to call "create()" or "update()" and NOT "save()" when working
     * with the Table class.
     */
    public function change()
    {

    }
}

The AbstractMigration Class

All Phinx migrations extend from the AbstractMigration class. This class provides the necessary support to create your database migrations. Database migrations can transform your database in many ways such as creating new tables, inserting rows, adding indexes and modifying columns.

The Change Method

Phinx 0.2.0 introduced a new feature called reversible migrations. This feature has now become the default migration method. With reversible migrations you only need to define the up logic and Phinx can figure out how to migrate down automatically for you. For example:

<?php

use Phinx\Migration\AbstractMigration;

class CreateUserLoginsTable extends AbstractMigration
{
    /**
     * Change Method.
     *
     * More information on this method is available here:
     * http://docs.phinx.org/en/latest/migrations.html#the-change-method
     *
     * Uncomment this method if you would like to use it.
     */
    public function change()
    {
        // create the table
        $table = $this->table('user_logins');
        $table->addColumn('user_id', 'integer')
              ->addColumn('created', 'datetime')
              ->create();
    }

    /**
     * Migrate Up.
     */
    public function up()
    {

    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

When executing this migration Phinx will create the user_logins table on the way up and automatically figure out how to drop the table on the way down. Please be aware that when a change method exists Phinx will automatically ignore the up and down methods. If you need to use these methods it is recommended to create a separate migration file.

Note

When creating or updating tables inside a change() method you must use the Table create() and update() methods. Phinx cannot automatically determine whether a save() call is creating a new table or modifying an existing one.

Phinx can only reverse the following commands:

  • createTable
  • renameTable
  • addColumn
  • renameColumn
  • addIndex
  • addForeignKey

If a command cannot be reversed then Phinx will throw a IrreversibleMigrationException exception when it’s migrating down.

The Up Method

The up method is automatically run by Phinx when you are migrating up and it detects the given migration hasn’t been executed previously. You should use the up method to transform the database with your intended changes.

The Down Method

The down method is automatically run by Phinx when you are migrating down and it detects the given migration has been executed in the past. You should use the down method to reverse/undo the transformations described in the up method.

Executing Queries

Queries can be executed with the execute() and query() methods. The execute() method returns the number of affected rows whereas the query() method returns the result as a PDOStatement

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        // execute()
        $count = $this->execute('DELETE FROM users'); // returns the number of affected rows

        // query()
        $rows = $this->query('SELECT * FROM users'); // returns the result as an array
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Note

These commands run using the PHP Data Objects (PDO) extension which defines a lightweight, consistent interface for accessing databases in PHP. Always make sure your queries abide with PDOs before using the execute() command. This is especially important when using DELIMITERs during insertion of stored procedures or triggers which don’t support DELIMITERs.

Fetching Rows

There are two methods available to fetch rows. The fetchRow() method will fetch a single row, whilst the fetchAll() method will return multiple rows. Both methods accept raw SQL as their only parameter.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        // fetch a user
        $row = $this->fetchRow('SELECT * FROM users');

        // fetch an array of messages
        $rows = $this->fetchAll('SELECT * FROM messages');
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Inserting Data

Phinx makes it easy to insert data into your tables. Whilst this feature is intended for the seed feature, you are also free to use the insert methods in your migrations.

<?php

use Phinx\Migration\AbstractMigration;

class NewStatus extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        // inserting only one row
        $singleRow = [
            'id'    => 1,
            'name'  => 'In Progress'
        ]

        $table = $this->table('status');
        $table->insert($singleRow);
        $table->saveData();

        // inserting multiple rows
        $rows = [
            [
              'id'    => 2,
              'name'  => 'Stopped'
            ],
            [
              'id'    => 3,
              'name'  => 'Queued'
            ]
        ];

        // this is a handy shortcut
        $this->insert('status', $rows);
    }

    /**
     * Migrate Down.
     */
    public function down()
    {
        $this->execute('DELETE FROM status');
    }
}

Note

You cannot use the insert methods inside a change() method. Please use the up() and down() methods.

Working With Tables

The Table Object

The Table object is one of the most useful APIs provided by Phinx. It allows you to easily manipulate database tables using PHP code. You can retrieve an instance of the Table object by calling the table() method from within your database migration.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('tableName');
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

You can then manipulate this table using the methods provided by the Table object.

The Save Method

When working with the Table object Phinx stores certain operations in a pending changes cache.

When in doubt it is recommended you call this method. It will commit any pending changes to the database.

Creating a Table

Creating a table is really easy using the Table object. Let’s create a table to store a collection of users.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $users = $this->table('users');
        $users->addColumn('username', 'string', array('limit' => 20))
              ->addColumn('password', 'string', array('limit' => 40))
              ->addColumn('password_salt', 'string', array('limit' => 40))
              ->addColumn('email', 'string', array('limit' => 100))
              ->addColumn('first_name', 'string', array('limit' => 30))
              ->addColumn('last_name', 'string', array('limit' => 30))
              ->addColumn('created', 'datetime')
              ->addColumn('updated', 'datetime', array('null' => true))
              ->addIndex(array('username', 'email'), array('unique' => true))
              ->save();
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Columns are added using the addColumn() method. We create a unique index for both the username and email columns using the addIndex() method. Finally calling save() commits the changes to the database.

Note

Phinx automatically creates an auto-incrementing primary key column called id for every table.

The id option sets the name of the automatically created identity field, while the primary_key option selects the field or fields used for primary key. The primary_key option always defaults to the value of id. Both can be disabled by setting them to false.

To specify an alternate primary key you can specify the primary_key option when accessing the Table object. Let’s disable the automatic id column and create a primary key using two columns instead:

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('followers', array('id' => false, 'primary_key' => array('user_id', 'follower_id')));
        $table->addColumn('user_id', 'integer')
              ->addColumn('follower_id', 'integer')
              ->addColumn('created', 'datetime')
              ->save();
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Setting a single primary_key doesn’t enable the AUTO_INCREMENT option. To simply change the name of the primary key, we need to override the default id field name:

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('followers', array('id' => 'user_id'));
        $table->addColumn('follower_id', 'integer')
              ->addColumn('created', 'timestamp', array('default' => 'CURRENT_TIMESTAMP'))
              ->save();
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Valid Column Types

Column types are specified as strings and can be one of:

  • biginteger
  • binary
  • boolean
  • date
  • datetime
  • decimal
  • float
  • integer
  • string
  • text
  • time
  • timestamp
  • uuid

In addition, the MySQL adapter supports enum, set, blob and json column types. (json in MySQL 5.7 and above)

In addition, the Postgres adapter supports smallint, json, jsonb and uuid column types (PostgreSQL 9.3 and above).

For valid options, see the Valid Column Options below.

Determining Whether a Table Exists

You can determine whether or not a table exists by using the hasTable() method.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $exists = $this->hasTable('users');
        if ($exists) {
            // do something
        }
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Dropping a Table

Tables can be dropped quite easily using the dropTable() method. It is a good idea to recreate the table again in the down() method.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $this->dropTable('users');
    }

    /**
     * Migrate Down.
     */
    public function down()
    {
        $users = $this->table('users');
        $users->addColumn('username', 'string', array('limit' => 20))
              ->addColumn('password', 'string', array('limit' => 40))
              ->addColumn('password_salt', 'string', array('limit' => 40))
              ->addColumn('email', 'string', array('limit' => 100))
              ->addColumn('first_name', 'string', array('limit' => 30))
              ->addColumn('last_name', 'string', array('limit' => 30))
              ->addColumn('created', 'datetime')
              ->addColumn('updated', 'datetime', array('null' => true))
              ->addIndex(array('username', 'email'), array('unique' => true))
              ->save();
    }
}

Renaming a Table

To rename a table access an instance of the Table object then call the rename() method.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('users');
        $table->rename('legacy_users');
    }

    /**
     * Migrate Down.
     */
    public function down()
    {
        $table = $this->table('legacy_users');
        $table->rename('users');
    }
}

Working With Columns

Valid Column Types

Column types are specified as strings and can be one of:

  • biginteger
  • binary
  • boolean
  • char
  • date
  • datetime
  • decimal
  • float
  • integer
  • string
  • text
  • time
  • timestamp
  • uuid

In addition, the MySQL adapter supports enum, set and blob column types.

In addition, the Postgres adapter supports smallint, json, jsonb and uuid column types (PostgreSQL 9.3 and above).

Valid Column Options

The following are valid column options:

For any column type:

Option Description
limit set maximum length for strings, also hints column types in adapters (see note below)
length alias for limit
default set default value or action
null allow NULL values (should not be used with primary keys!)
after specify the column that a new column should be placed after
comment set a text comment on the column

For decimal columns:

Option Description
precision combine with scale set to set decimal accuracy
scale combine with precision to set decimal accuracy
signed enable or disable the unsigned option (only applies to MySQL)

For enum and set columns:

Option Description
values Can be a comma separated list or an array of values

For integer and biginteger columns:

Option Description
identity enable or disable automatic incrementing
signed enable or disable the unsigned option (only applies to MySQL)

For timestamp columns:

Option Description
default set default value (use with CURRENT_TIMESTAMP)
update set an action to be triggered when the row is updated (use with CURRENT_TIMESTAMP)
timezone enable or disable the with time zone option for time and timestamp columns (only applies to Postgres)

You can add created_at and updated_at timestamps to a table using the addTimestamps() method. This method also allows you to supply alternative names.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Change.
     */
    public function change()
    {
        // Override the 'updated_at' column name with 'amended_at'.
        $table = $this->table('users')->addTimestamps(null, 'amended_at')->create();
    }
}

For boolean columns:

Option Description
signed enable or disable the unsigned option (only applies to MySQL)

For foreign key definitions:

Option Description
update set an action to be triggered when the row is updated
delete set an action to be triggered when the row is deleted

You can pass one or more of these options to any column with the optional third argument array.

Limit Option and PostgreSQL

When using the PostgreSQL adapter, additional hinting of database column type can be made for integer columns. Using limit with one the following options will modify the column type accordingly:

Limit Column Type
INT_SMALL SMALLINT
use Phinx\Db\Adapter\PostgresAdapter;

//...

$table = $this->table('cart_items');
$table->addColumn('user_id', 'integer')
      ->addColumn('subtype_id', 'integer', array('limit' => PostgresAdapter::INT_SMALL))
      ->create();

Limit Option and MySQL

When using the MySQL adapter, additional hinting of database column type can be made for integer, text and blob columns. Using limit with one the following options will modify the column type accordingly:

Limit Column Type
BLOB_TINY TINYBLOB
BLOB_REGULAR BLOB
BLOB_MEDIUM MEDIUMBLOB
BLOB_LONG LONGBLOB
TEXT_TINY TINYTEXT
TEXT_REGULAR TEXT
TEXT_MEDIUM MEDIUMTEXT
TEXT_LONG LONGTEXT
INT_TINY TINYINT
INT_SMALL SMALLINT
INT_MEDIUM MEDIUMINT
INT_REGULAR INT
INT_BIG BIGINT
use Phinx\Db\Adapter\MysqlAdapter;

//...

$table = $this->table('cart_items');
$table->addColumn('user_id', 'integer')
      ->addColumn('product_id', 'integer', array('limit' => MysqlAdapter::INT_BIG))
      ->addColumn('subtype_id', 'integer', array('limit' => MysqlAdapter::INT_SMALL))
      ->addColumn('quantity', 'integer', array('limit' => MysqlAdapter::INT_TINY))
      ->create();

Get a column list

To retrieve all table columns, simply create a table object and call getColumns() method. This method will return an array of Column classes with basic info. Example below:

<?php

use Phinx\Migration\AbstractMigration;

class ColumnListMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $columns = $this->table('users')->getColumns();
        ...
    }

    /**
     * Migrate Down.
     */
    public function down()
    {
        ...
    }
}

Checking whether a column exists

You can check if a table already has a certain column by using the hasColumn() method.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Change Method.
     */
    public function change()
    {
        $table = $this->table('user');
        $column = $table->hasColumn('username');

        if ($column) {
            // do something
        }

    }
}

Renaming a Column

To rename a column access an instance of the Table object then call the renameColumn() method.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('users');
        $table->renameColumn('bio', 'biography');
    }

    /**
     * Migrate Down.
     */
    public function down()
    {
        $table = $this->table('users');
        $table->renameColumn('biography', 'bio');
    }
}

Adding a Column After Another Column

When adding a column you can dictate its position using the after option.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Change Method.
     */
    public function change()
    {
        $table = $this->table('users');
        $table->addColumn('city', 'string', array('after' => 'email'))
              ->update();
    }
}

Dropping a Column

To drop a column, use the removeColumn() method.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate up.
     */
    public function up()
    {
        $table = $this->table('users');
        $table->removeColumn('short_name')
              ->save();
    }
}

Specifying a Column Limit

You can limit the maximum length of a column by using the limit option.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Change Method.
     */
    public function change()
    {
        $table = $this->table('tags');
        $table->addColumn('short_name', 'string', array('limit' => 30))
              ->update();
    }
}

Changing Column Attributes

To change column type or options on an existing column, use the changeColumn() method. See `Valid Column Types`_ and Valid Column Options for allowed values.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $users = $this->table('users');
        $users->changeColumn('email', 'string', array('limit' => 255))
              ->save();
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Working With Indexes

To add an index to a table you can simply call the addIndex() method on the table object.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('users');
        $table->addColumn('city', 'string')
              ->addIndex(array('city'))
              ->save();
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

By default Phinx instructs the database adapter to create a normal index. We can pass an additional parameter unique to the addIndex() method to specify a unique index. We can also explicitly specify a name for the index using the name parameter.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('users');
        $table->addColumn('email', 'string')
              ->addIndex(array('email'), array('unique' => true, 'name' => 'idx_users_email'))
              ->save();
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

The MySQL adapter also supports fulltext indexes. If you are using a version before 5.6 you must ensure the table uses the MyISAM engine.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    public function change()
    {
        $table = $this->table('users', ['engine' => 'MyISAM']);
        $table->addColumn('email', 'string')
              ->addIndex('email', ['type' => 'fulltext'])
              ->create();
    }
}

Removing indexes is as easy as calling the removeIndex() method. You must call this method for each index.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('users');
        $table->removeIndex(array('email'));
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Note

There is no need to call the save() method when using removeIndex(). The index will be removed immediately.

Working With Foreign Keys

Phinx has support for creating foreign key constraints on your database tables. Let’s add a foreign key to an example table:

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('tags');
        $table->addColumn('tag_name', 'string')
              ->save();

        $refTable = $this->table('tag_relationships');
        $refTable->addColumn('tag_id', 'integer')
                 ->addForeignKey('tag_id', 'tags', 'id', array('delete'=> 'SET_NULL', 'update'=> 'NO_ACTION'))
                 ->save();

    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

“On delete” and “On update” actions are defined with a ‘delete’ and ‘update’ options array. Possibles values are ‘SET_NULL’, ‘NO_ACTION’, ‘CASCADE’ and ‘RESTRICT’.

It is also possible to pass addForeignKey() an array of columns. This allows us to establish a foreign key relationship to a table which uses a combined key.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('follower_events');
        $table->addColumn('user_id', 'integer')
              ->addColumn('follower_id', 'integer')
              ->addColumn('event_id', 'integer')
              ->addForeignKey(array('user_id', 'follower_id'),
                              'followers',
                              array('user_id', 'follower_id'),
                              array('delete'=> 'NO_ACTION', 'update'=> 'NO_ACTION'))
              ->save();
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

We can also easily check if a foreign key exists:

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('tag_relationships');
        $exists = $table->hasForeignKey('tag_id');
        if ($exists) {
            // do something
        }
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}

Finally to delete a foreign key use the dropForeignKey method.

<?php

use Phinx\Migration\AbstractMigration;

class MyNewMigration extends AbstractMigration
{
    /**
     * Migrate Up.
     */
    public function up()
    {
        $table = $this->table('tag_relationships');
        $table->dropForeignKey('tag_id');
    }

    /**
     * Migrate Down.
     */
    public function down()
    {

    }
}