docs/content/doc/development/migrations.md

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+---
+date: "2019-03-29:00:00+02:00"
+title: "Database migrations"
+draft: false
+type: "doc"
+menu:
+  sidebar:
+    parent: "development"
+---
+
+# Database Migrations
+
+Vikunja runs all database migrations automatically on each start if needed.
+Additionally, they can also be run directly by using the `migrate` command.
+
+We use [xormigrate](https://github.com/techknowlogick/xormigrate) to handle migrations, which is based on gormigrate.
+
+## Add a new migration
+
+All migrations are stored in `pkg/migrations` and files should have the same name as their id.
+
+Each migration should have a function to apply and roll it back, as well as a numeric id (the datetime)
+and a more in-depth description of what the migration actually does.
+
+To easily get a new id, run the following on any unix system: 
+
+```bash
+date +%Y%m%d%H%M%S
+```
+
+New migrations should be added via the `init()` function to the `migrations` variable.
+All migrations are sorted before being executed, since `init()` does not guarantee the order.
+
+### Example
+
+```go
+package migration
+
+import (
+	"github.com/go-xorm/xorm"
+	"src.techknowlogick.com/xormigrate"
+)
+
+// Used for rollback
+type teamMembersMigration20190328074430 struct {
+	Updated int64 `xorm:"updated"`
+}
+
+func (teamMembersMigration20190328074430) TableName() string {
+	return "team_members"
+}
+
+func init() {
+	migrations = append(migrations, &xormigrate.Migration{
+		ID:          "20190328074430",
+		Description: "Remove updated from team_members",
+		Migrate: func(tx *xorm.Engine) error {
+			return dropTableColum(tx, "team_members", "updated")
+		},
+		Rollback: func(tx *xorm.Engine) error {
+			return tx.Sync2(teamMembersMigration20190328074430{})
+		},
+	})
+}
+```
+
+You should always copy the changed parts of the struct you're changing when adding migraitons.