schema-change

name	schema-change
description	Use when changing the db-scheduler database schema (adding/removing/altering columns, indexes, or the scheduled_tasks table). Walks through the lock-step update across every supported DB dialect, the matching JdbcCustomization changes, and the documentation copies. Skip for code-only changes that don't touch table structure.

Schema change checklist

The library supports six DB dialects and ships DDL for each. A schema change that misses one dialect ships a broken release. Treat this as a single atomic change.

1. DDL files (test resources)

Update all six in lock-step. Path: db-scheduler/src/test/resources/

• hsql_tables.sql
• postgresql_tables.sql
• mysql_tables.sql
• mariadb_tables.sql
• mssql_tables.sql
• oracle_tables.sql

Read all six first; column ordering and types differ per dialect (e.g. TIMESTAMP WITH TIME ZONE vs DATETIME2 vs TIMESTAMP(6) WITH TIME ZONE). Don't blindly copy from one dialect to another — preserve each dialect's existing type conventions.

There's also postgresql_custom_tablename.sql under src/test/resources/com/github/kagkarlsson/scheduler/ — check whether your change needs to be reflected there too (it tests configurable table name; usually yes if columns change).

2. JdbcCustomization classes

Path: db-scheduler/src/main/java/com/github/kagkarlsson/scheduler/jdbc/

If your change affects how rows are read/written (new column, type change, nullable→ not-null, etc.), update each relevant class:

• DefaultJdbcCustomization.java — base behavior
• PostgreSqlJdbcCustomization.java
• OracleJdbcCustomization.java
• MssqlJdbcCustomization.java
• MySQLJdbcCustomization.java
• MySQL8JdbcCustomization.java
• MariaDBJdbcCustomization.java
• AutodetectJdbcCustomization.java — only if dialect-detection logic changes
• JdbcCustomization.java (interface) — if the contract itself changes

Also check JdbcTaskRepository.java and QueryBuilder.java for SQL that references the changed columns.

3. Documentation DDL copies

The README and/or docs/ may carry copies of the DDL for users. Grep for a column name from the table to find them:

grep -rn "scheduled_tasks" --include="*.md" .

Update any matching SQL blocks so users get the current schema.

4. Verify

mvn -pl db-scheduler test                                # PostgreSQL tests

Dialects other than PostgreSQL currently need to be tested on CI (need to run on amd64 arch).

5. Migration note for users

Schema changes are user-visible. Add a brief migration note to the changelog / release notes describing the required ALTER TABLE (per dialect if they differ).

6. Finalize

Run /finalize before committing.