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Class: MigrationRunner

Defined in: Data/Migration/MigrationRunner.ts:38

Applies the ordered migration sequence in packages/core/src/sql/migrations/ to a database, exactly once each, and records what it did.

Design points that matter:

  • Idempotent. Every migration is recorded in schema_migration and never re-run. Individual statements additionally carry @skip-if guards, so even a database whose ledger was lost -- or one dragged partway forward by the older hard-coded migrator in electron/utils/initMainDatabase.ts -- lands in the same place.

  • Atomic per migration. Each migration runs inside one transaction. A failure rolls that migration back entirely; migrations that already succeeded stay applied and are not repeated.

  • Foreign keys off, then verified. Dropping a CHECK in SQLite means rebuilding the table, which is only safe with foreign_keys disabled. PRAGMA foreign_keys is a no-op inside a transaction, so it is toggled around it, and PRAGMA foreign_key_check runs inside the transaction before commit -- a violation therefore rolls back rather than persisting.

Constructors​

Constructor​

new MigrationRunner(sql, target): MigrationRunner

Defined in: Data/Migration/MigrationRunner.ts:46

Parameters​

sql​

ISql

Database to migrate.

target​

"main" | "user"

Which database this connection is -- 'main' or 'user'. Migrations aimed at the other one are skipped.

Returns​

MigrationRunner

Methods​

baseline()​

baseline(scripts): MigrationRunResult

Defined in: Data/Migration/MigrationRunner.ts:101

Record every migration as applied without running any of it.

For a database just created from sql/schemas/initial/, which already has the v2 structure. Replaying history against it would be wasted work at best. Migrations added after the baseline still run normally on the next run().

Parameters​

scripts​

MigrationScript[]

Returns​

MigrationRunResult

getApplied()​

getApplied(): AppliedMigration[]

Defined in: Data/Migration/MigrationRunner.ts:136

Rows of the ledger, oldest first.

Returns​

AppliedMigration[]

getPending()​

getPending(scripts): MigrationScript[]

Defined in: Data/Migration/MigrationRunner.ts:151

Migrations targeting this database that run() would apply.

Parameters​

scripts​

MigrationScript[]

Returns​

MigrationScript[]

run()​

run(scripts): MigrationRunResult

Defined in: Data/Migration/MigrationRunner.ts:54

Apply every migration in scripts that targets this database and has not been applied yet, in version order.

Parameters​

scripts​

MigrationScript[]

Returns​

MigrationRunResult