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MountSQLiMountSQLI

Generate

migrate generate diffs your code-defined tables against the live database and writes a SQL migration file. It does not apply it.

Syntax

Section titled “Syntax”
Terminal window
mountsqli migrate generate

The CLI auto-detects mountsqli.config.* from the current directory.

What it does

Section titled “What it does”
  1. Reads your tables from the config.
  2. Introspects the live database (or an empty schema on first run).
  3. Diffs the two and generates CREATE / ALTER / DROP statements.
  4. Writes a timestamped migration file to your migrations directory.

Example output

Section titled “Example output”
$ mountsqli migrate generate
Created migration: migrations/2026-07-16T12-00-00_add_posts.sql
-- migrations/2026-07-16T12-00-00_add_posts.sql
CREATE TABLE "posts" (
  "id" INTEGER PRIMARY KEY,
  "title" TEXT NOT NULL,
  "body" TEXT
);

Options

Section titled “Options”
Flag Effect
--name <n> set a custom migration name
--dir <path> override the migrations directory

Run it with your package manager:

Terminal window
npx mountsqli migrate generate

Best practices

Section titled “Best practices”
  • Generate after every schema change, before committing.
  • Review the SQL — destructive DROP/ALTER is shown explicitly.
  • Keep one logical change per migration for easy rollback reasoning.

Common mistakes

Section titled “Common mistakes”
  • Generating against :memory: — nothing persists, so diffs are always full creates.
  • Forgetting to commit the generated file.
Section titled “Related”