Scheman

SQL schema parser.

Usage

Create diff from 2 schema files.

require "scheman"

before = <<-SQL
CREATE TABLE `table1` (
  `column1` INTEGER(11) PRIMARY KEY NOT NULL AUTO INCREMENT,
  `column2` DATETIME DEFAULT NOW()
);

CREATE TABLE `table2` (
  `column1` INTEGER(11) NOT NULL AUTO INCREMENT,
  PRIMARY KEY (`column1`)
);
SQL

after = <<-SQL
CREATE TABLE `table1` (
  `column1` CHAR(11) NOT NULL AUTO INCREMENT,
  `column2` DATETIME DEFAULT CURRENT_TIMESTAMP(),
  `column3` VARCHAR(255) NOT NULL DEFAULT "a",
  PRIMARY KEY (`column2`)
);

CREATE TABLE `table3` (
  `column1` INTEGER(11) NOT NULL AUTO INCREMENT,
  PRIMARY KEY (`column1`)
);
SQL

puts Scheman::Diff.new(before: before, after: after, type: "mysql")

The result would be the following:

BEGIN;

SET foreign_key_checks=0;

CREATE TABLE `table3` (
  `column1` INTEGER(11) NOT NULL AUTO INCREMENT,
  PRIMARY KEY (`column1`)
);

ALTER TABLE `table1` ADD COLUMN `column3` VARCHAR(255) NOT NULL DEFAULT "a",
  CHANGE COLUMN `column1` CHAR(11) NOT NULL AUTO INCREMENT,
  DROP PRIMARY KEY,
  ADD PRIMARY KEY `column2`;

DROP TABLE `table2`;

SET foreign_key_checks=1;

COMMIT;