Method: Sequel::Schema::CreateTableGenerator#column

Defined in:

lib/sequel/database/schema_generator.rb

#column(name, type, opts = OPTS) ⇒ Object

Add a column with the given name, type, and opts:

column :num, :integer
# num INTEGER

column :name, String, null: false, default: 'a'
# name varchar(255) NOT NULL DEFAULT 'a'

inet :ip
# ip inet

You can also create columns via method missing, so the following are equivalent:

column :number, :integer
integer :number

The following options are supported:

:collate

The collation to use for the column. For backwards compatibility, only symbols and string values are supported, and they are used verbatim. However, on PostgreSQL, symbols are literalized as regular identifiers, since unquoted collations are unlikely to be valid.

:default

The default value for the column.

:deferrable

For foreign key columns, this ensures referential integrity will work even if referencing table uses a foreign key value that does not yet exist on referenced table (but will exist before the transaction commits). Basically it adds DEFERRABLE INITIALLY DEFERRED on key creation. If you use :immediate as the value, uses DEFERRABLE INITIALLY IMMEDIATE.

:generated_always_as

Specify a GENERATED ALWAYS AS column expression, if generated columns are supported (PostgreSQL 12+, MariaDB 5.2.0+, and MySQL 5.7.6+).

:index

Create an index on this column. If given a hash, use the hash as the options for the index.

:key

For foreign key columns, the column in the associated table that this column references. Unnecessary if this column references the primary key of the associated table, except if you are using MySQL.

:null

Mark the column as allowing NULL values (if true), or not allowing NULL values (if false). The default is to allow NULL values.

:on_delete

Specify the behavior of this column when being deleted (:restrict, :cascade, :set_null, :set_default, :no_action).

:on_update

Specify the behavior of this column when being updated (:restrict, :cascade, :set_null, :set_default, :no_action).

:primary_key

Make the column as a single primary key column. This should not be used if you want a single autoincrementing primary key column (use the primary_key method in that case).

:primary_key_constraint_name

The name to give the primary key constraint

:primary_key_deferrable

Similar to :deferrable, but for the primary key constraint if :primary_key is used.

:type

Overrides the type given as the argument. Generally not used by column itself, but can be passed as an option to other methods that call column.

:unique

Mark the column as unique, generally has the same effect as creating a unique index on the column.

:unique_constraint_name

The name to give the unique key constraint

:unique_deferrable

Similar to :deferrable, but for the unique constraint if :unique is used.

PostgreSQL specific options:

:identity

Create an identity column.

MySQL specific options:

:generated_type

Set the type of column when using :generated_always_as, should be :virtual or :stored to force a type.

:on_update_current_timestamp

Use ON UPDATE CURRENT TIMESTAMP when defining the column, which will update the column value to CURRENT_TIMESTAMP on every UPDATE.

Microsoft SQL Server specific options:

:clustered

When using :primary_key or :unique, marks the primary key or unique constraint as CLUSTERED (if true), or NONCLUSTERED (if false).

# File 'lib/sequel/database/schema_generator.rb', line 157

def column(name, type, opts = OPTS)
  columns << {:name => name, :type => type}.merge!(opts)
  if index_opts = opts[:index]
    index(name, index_opts.is_a?(Hash) ? index_opts : OPTS)
  end
  nil
end