apply

Applies a migration pack file to the production database. All statements are executed inside a single transaction — either everything commits or everything rolls back.

Usage

deepdiffdb apply --pack diff-output/migration_pack.sql --config deepdiffdb.config.yaml

What It Does

1. Reads and parses the migration pack SQL file.
2. Opens a connection to the production database (as defined in the config file).
3. Begins a database transaction.
4. Executes each statement in order.
5. On success: commits the transaction.
6. On any error: rolls back the transaction automatically, leaving production unchanged.

Flags

Flag	Required	Description
--pack	Yes	Path to the migration pack SQL file
--config	No	Path to the configuration file (default: deepdiffdb.config.yaml)
--dry-run	No	Validate the SQL without executing it
--resume	No	Resume from the last saved checkpoint
--verbose	No	Enable debug-level logging
--log-level	No	Minimum log level: debug, info, warn, error (default: info)
--log-format	No	Log output format: text or json (default: text)
--log-file	No	Write logs to this file in addition to stdout

Dry Run Mode

Use --dry-run to parse and validate the pack without executing any statements:

deepdiffdb apply --pack diff-output/migration_pack.sql --dry-run

Dry run output:

Dry-run mode: no changes will be applied.
Parsed 31 statements.
Validation passed.

Example — Live Apply

deepdiffdb apply \
  --pack diff-output/migration_pack.sql \
  --config deepdiffdb.config.yaml \
  --log-format json \
  --log-file apply.log

Expected output on success:

Applying migration pack: diff-output/migration_pack.sql
Statements executed: 31
Transaction committed.
Apply complete.

Resume an Interrupted Apply

If apply is interrupted mid-way:

deepdiffdb apply \
  --pack diff-output/migration_pack.sql \
  --config deepdiffdb.config.yaml \
  --resume

DeepDiff DB loads the last apply checkpoint and continues from the last committed batch. See Checkpoint and Resume for details.

Safety Notes

• apply only writes to the production database; it never reads from or writes to the dev database.
• The migration pack is generated by gen-pack — always review migration_pack.sql before running apply.
• Use --dry-run in CI to validate the pack before scheduling a maintenance window.
• If the transaction rolls back, the error message includes the failing statement for quick diagnosis.

Exit Codes

Code	Meaning
0	Apply completed successfully
1	Apply failed; transaction was rolled back