Migrations on DPG — Declarative PG

Lifecycle Directives

Mon, 01 Jan 0001 00:00:00 +0000

Lifecycle directives live inside { } blocks. They communicate intent to the compiler for operations that cannot be expressed as a simple CREATE or ALTER.

RENAMED FROM — object renames

Schema rename

SCHEMA reporting {
 RENAMED FROM old_reporting;
}

-- emits
ALTER SCHEMA "old_reporting" RENAME TO "reporting";

Table rename

TABLE user_accounts ( ... )
{
 RENAMED FROM users;
}

-- emits
ALTER TABLE "public"."users" RENAME TO "user_accounts";

Column rename

The new name goes in both the ( ) list and the COLUMN block. The old name appears only in RENAMED FROM.

Linting

Mon, 01 Jan 0001 00:00:00 +0000

The linter runs automatically as part of dpg plan, dpg apply, and dpg validate. It runs over the merged IR before any SQL is generated. Lint errors abort the command. Lint warnings are printed to stderr but do not block.

Configuration

# dpg.toml
[linter]
warn_on_deprecated = true # default
require_column_comments = false # default
forbid_hardcoded_passwords = true # default
max_columns_per_table = 50 # default: 50 (0 = disabled)

`deprecated`

Severity: Warning — Config: warn_on_deprecated — Default: enabled

Warns when a table, column, view, or function is marked DEPRECATED.

Drift Detection

Mon, 01 Jan 0001 00:00:00 +0000

dpg verify reads the live PostgreSQL catalog and compares it with the committed snapshot: the state DPG last applied. Only properties your source declares are compared. A property PostgreSQL reports but you never declared (an owner, a column’s storage mode, a role attribute left at its default) is never drift.

dpg verify
dpg verify --cluster production --database myapp
dpg verify --format json

Exit codes: 0 no drift (unmanaged objects, warnings and acknowledged items are allowed), 1 drift found, 2 error.