Database schema operation

3. database meta information

xorm provides methods to getting and setting table schema. For less schema changing production, engine.Sync2() is enough.

3.1 retrieve database meta info

  • DBMetas()

engine.DBMetas() returns all tables schema information.

3.2.directly table operation

  • CreateTables()

engine.CreateTables(struct) creates table with struct or struct pointer. engine.Charset() and engine.StoreEngine() can change charset or storage engine for mysql database.

  • IsTableEmpty()

check table is empty or not.

  • IsTableExist()

check table is existed or not.

  • DropTables()

engine.DropTables(struct) drops table and indexes with struct or struct pointer. engine.DropTables(string) only drops table except indexes.

3.3.create indexes and uniques

  • CreateIndexes create indexes with struct.
  • CreateUniques create unique indexes with struct.

3.4.Synchronize database schema

xorm watches tables and indexes and sync schema:

  1. use table name to create or drop table
  2. use column name to alter column
  3. use the indexes definition in struct field tag to create or drop indexes.
1. err := engine.Sync2(new(User))