Setup

The updater reads its files from your resources. Create this structure:

src/main/resources
└── database
    ├── postgresql
    │   └── 1
    │       └── setup.sql
    └── version

The version file

database/version holds the version of your schema: the major and the patch number, separated by a dot.

1.0

Patch 0 means only setup.sql. Every patch you add raises the patch number.

If database/version is missing, the updater fails with a FileNotFoundException. Set the version with setVersion(...) on the builder if you do not want a version file.

One directory per database

Each database has its own directory. Its name is the name of the database:

Database	Directory
PostgreSQL	`database/postgresql`
MariaDB	`database/mariadb`
MySQL	`database/mysql`
SQLite	`database/sqlite`

If your application supports several databases, every directory needs the same files. A file may be empty when a database needs no change.

Inside, each major version has its own directory, starting with 1.

The setup script

setup.sql creates your schema in the state of version <major>.0:

CREATE TABLE IF NOT EXISTS users
(
    id   SERIAL PRIMARY KEY,
    name TEXT NOT NULL
);

CREATE TABLE IF NOT EXISTS birthdays
(
    user_id  INTEGER NOT NULL REFERENCES users (id),
    birthday DATE    NOT NULL
);

End every statement with a semicolon.

How a file is sent to the database depends on the database:

PostgreSQL gets the whole file at once.
MariaDB, MySQL and SQLite get one statement at a time. SADU splits the file at each ;.

To keep a ; inside a statement, for example in a trigger, change the delimiter with a DELIMITER line:

DELIMITER $$
CREATE TRIGGER trim_name BEFORE INSERT ON users
FOR EACH ROW
BEGIN
    SET NEW.name = TRIM(NEW.name);
END$$
DELIMITER ;

The splitter is simple. It also splits at a ; inside a string or a comment, so avoid those there.

Next: Run the updater.

The version file​

One directory per database​

The setup script​

The version file

One directory per database

The setup script