CLI

The asc db sync command compares your .as definitions against the live database and applies changes. It is part of the @atscript/typescript CLI.

Basic Usage

npx asc db sync

This will:

1. Compile your .as files
2. Connect to the database using your config
3. Show a detailed plan of what will change
4. Ask for confirmation before applying destructive changes
5. Apply changes and show the result

If the schema hash is unchanged since the last sync, the command exits after a quick hash comparison — no schema introspection, no DDL, no locking.

Flags

Flag	Description
--dry-run	Show the plan without applying any changes
--yes	Skip the confirmation prompt (CI mode)
--force	Re-sync even if the schema hash matches
--safe	Skip destructive operations (column drops, table drops, type changes)
-c, --config	Path to atscript.config.mts (auto-resolved if omitted)

--dry-run

Shows exactly what would change without touching the database. Use this to preview changes before applying:

npx asc db sync --dry-run

--yes

Skips the interactive confirmation prompt. Non-destructive changes are always applied without prompting; --yes extends this to destructive changes as well:

npx asc db sync --yes

--force

Bypasses the hash-based change detection. The command will introspect the database and diff against your .as definitions regardless of whether the stored hash matches:

npx asc db sync --force

--safe

Suppresses all destructive operations (column drops, table drops, type changes requiring recreation). Only additive changes are applied. See Safe Mode for details.

npx asc db sync --safe

Output Format

The CLI displays a structured plan grouped by tables and views. Each entry shows a status indicator:

Symbol	Color	Meaning
+	Green	New table/column/FK will be created
~	Cyan	Existing table will be modified
-	Red	Table/column/FK will be dropped
!	Red	Type change or destructive operation
✓	Green	Already in sync
✗	Red	Error (rename conflict, missing sync method)

Example output

Tables:
  + users — create
      + id (number) PK — add
      + name (string) — add
      + email (string) — add

  ~ posts — alter
      + published_at (number) — add
      ~ title_text → title — rename
      - old_column — drop

  ✓ comments — in sync

Views:
  + active_users — create
  ✓ [V] user_stats — in sync

After applying changes, the result summary shows what was actually done:

Schema synced successfully. Hash: a1b2c3d4

Tables:
  + users — created
      + id — added
      + name — added
      + email — added

  ~ posts — altered
      + published_at — added
      ~ title_text — renamed
      - old_column — dropped

Examples

Preview changes without applying:

npx asc db sync --dry-run

Auto-approve for CI/CD pipelines:

npx asc db sync --yes

Safe mode — only additive changes:

npx asc db sync --safe

Force a full re-sync, ignoring the stored hash:

npx asc db sync --force

Use a specific config file:

npx asc db sync -c ./config/atscript.config.mts

Combine flags for CI with safe mode:

npx asc db sync --yes --safe

Error Handling

The CLI exits with a non-zero code when:

• No db config — the atscript.config.mts has no db field
• Schema errors — rename conflicts, type changes without @db.sync.method, or external view validation failures
• Adapter not found — the specified adapter package is not installed

When errors are detected in the plan, the CLI prints the errors and exits without applying any changes.

Exit Codes

Code	Meaning
0	Success — sync completed, was up-to-date, or --dry-run printed
Non-0	Schema errors, connection failure, missing config, or user abort

asc exposes --help and --version from the underlying @atscript/typescript CLI; both exit with 0.

Next Steps

• Configuration — config file setup for schema sync
• What Gets Synced — detailed change categories
• How Sync Works — architecture and internals