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Flyway Documentation

This documentation site is not updated. The new documentation can now be found on documentation.red-gate.com

Poll

Cherry Pick

Flyway Teams

Description

A Comma separated list of migrations that Flyway should consider when migrating, undoing, or repairing. Migrations are considered in the order that they are supplied, overriding the default ordering. Leave blank to consider all discovered migrations.
Note that when used in conjunction with undo, the migrations are undone in reverse to how they are specified to cherryPick i.e. flyway undo -cherryPick=3,2,1 will undo migrations in the order 1,2,3.

Each item in the list must either be a valid migration version (e.g 2.1) or a valid migration description (e.g. create_table).

For example:

  • Create migrations V1__create_table1.sql, V2__create_table2.sql, and R__create_view.sql
  • Run flyway migrate -cherryPick="1,create_view"

The schema history table now shows migration V1 and create_view as being successfully applied. However V2 has been skipped and is marked as ‘ignored’. V2__create_table2.sql can be cherry picked for deployment at a later time.

Usage

Commandline

./flyway -cherryPick="2.0" migrate

Configuration File

flyway.cherryPick=2.0

Environment Variable

FLYWAY_CHERRY_PICK=2.0

API

Flyway.configure()
    .cherryPick("2.0")
    .load()

Gradle

flyway {
    cherryPick = '2.0'
}

Maven

<configuration>
    <cherryPick>2.0</cherryPick>
</configuration>

Use Cases

Deferred migration execution

Let’s say you have a project with 3 migrations:

V1__fastCreate1.sql
V2__slowInsert2.sql
V3__fastCreate3.sql

Migration V2 takes a tremendously large amount of time to execute so you decide executing it overnight would be better, but still need to execute migrations V1 and V3. Without cherryPick this would involve deleting V2 from disk and adding it back when needed which is a tedious and error prone task. Using cherryPick we can simply migrate V1 and V3 immediately:

flyway migrate -cherryPick="1,3"

When it comes to migrating V2, we can utilise outOfOrder as follows:

flyway migrate -outOfOrder="true"

Undo out of order

By default undo will undo migrations starting with the latest applied migration. With cherryPick you can undo migrations out of order, targetting specific migrations to undo.

Let’s assume the following 3 migrations are applied, and all have an available undo migration:

V1__first.sql
V2__second.sql
V3__third.sql

If we only want to undo migration V2 we can run:

flyway undo -cherryPick="2"

This will let us target any migration to undo out of order.