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payloadcms/docs/database/migrations.mdx
2023-12-04 15:09:21 -05:00

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---
title: Migrations
label: Migrations
order: 20
keywords: database, migrations, ddl, sql, mongodb, postgres, documentation, Content Management System, cms, headless, typescript, node, react, express
desc: Payload features first-party database migrations all done in TypeScript.
---
Payload exposes a full suite of migration controls available for your use. Migration commands are accessible via the `npm run payload` command in your project directory.
Ensure you have an npm script called "payload" in your `package.json` file.
```json
{
"scripts": {
"payload": "cross-env PAYLOAD_CONFIG_PATH=src/payload.config.ts payload"
}
}
```
<Banner>
Note that you need to run Payload migrations through the package manager that you are using, because Payload should not be globally installed on your system.
</Banner>
### Migration file contents
Payload stores all created migrations in a folder that you can specify. By default, migrations are stored in `./src/migrations`.
A migration file has two exports - an `up` function, which is called when a migration is executed, and a `down` function that will be called if for some reason the migration fails to complete successfully. The `up` function should contain all changes that you attempt to make within the migration, and the `down` should ideally revert any changes you make.
For an added level of safety, migrations should leverage Payload [transactions](/docs/database/transactions).
Here is an example migration file:
```ts
import { MigrateUpArgs, MigrateDownArgs } from '@payloadcms/your-db-adapter'
export async function up({ payload }: MigrateUpArgs): Promise<void> {
// Perform changes to your database here.
// You have access to `payload` as an argument, and
// everything is done in TypeScript.
};
export async function down({ payload }: MigrateDownArgs): Promise<void> {
// Do whatever you need to revert changes if the `up` function fails
};
```
### Migrations Directory
Each DB adapter has an optional property `migrationDir` where you can override where you want your migrations to be stored/read. If this is not specified, Payload will check the default and possibly make a best effort to find your migrations directory by searching in common locations ie. `./src/migrations`, `./dist/migrations`, `./migrations`, etc.
All database adapters should implement similar migration patterns, but there will be small differences based on the adapter and its specific needs. Below is a list of all migration commands that should be supported by your database adapter.
## Commands
### Migrate
The `migrate` command will run any migrations that have not yet been run.
```text
npm run payload migrate
```
### Create
Create a new migration file in the migrations directory. You can optionally name the migration that will be created. By default, migrations will be named using a timestamp.
```text
npm run payload migrate:create optional-name-here
```
### Status
The `migrate:status` command will check the status of migrations and output a table of which migrations have been run, and which migrations have not yet run.
`payload migrate:status`
```text
npm run payload migrate:status
```
### Down
Roll back the last batch of migrations.
```text
npm run payload migrate:down
```
### Refresh
Roll back all migrations that have been run, and run them again.
```text
npm run payload migrate:refresh
```
### Reset
Roll back all migrations.
```text
npm run payload migrate:reset
```
### Fresh
Drops all entities from the database and re-runs all migrations from scratch.
```text
npm run payload migrate:fresh
```