Backfill | OKModel

backfill sets batch size, pause, and batch statement timeout.

batchSize is written into a new plan. pauseMs and statementTimeoutMs are read when the batches run.

Field	Required	Default	Role
`batchSize`	no	`1000`	Rows in `batch=` on a new plan.
`pauseMs`	no	`0`	Milliseconds after a committed batch, and not after the last one.
`statementTimeoutMs`	no	statement timeout, then `30000`	`statement_timeout` for one batch.

okmodel.config.ts

import { defineConfig } from "okmodel/migrate";

export default defineConfig({
  schema: "./schema.ts",
  database: process.env.DATABASE_URL!,
  backfill: { 
    batchSize: 1000,
    pauseMs: 50,
    statementTimeoutMs: 30_000,
  },
});

A new plan writes one header. It names the table, the key, and batch=. pauseMs and statementTimeoutMs stay out of the file.

migrations/20260301000000_init.sql

-- backfill table="public"."notes" key="id" batch=1000

Apply reads batch= from that line. Changing batchSize does not change a file that already exists.

Omit statementTimeoutMs and the batch uses the apply statement timeout, then 30 seconds. The batch lock_timeout is the apply lock timeout.

Refused

batchSize below 1, or not an integer, is refused: backfill.batchSize must be an integer of at least 1. A header whose batch is below 1 is refused.