# File lib/sequel/database/schema_generator.rb 301 def primary_key(name, *args) 302 return composite_primary_key(name, *args) if name.is_a?(Array) 303 column = @db.serial_primary_key_options.merge({:name => name}) 304 305 if opts = args.pop 306 opts = {:type => opts} unless opts.is_a?(Hash) 307 if type = args.pop 308 opts = opts.merge(:type => type) 309 end 310 column.merge!(opts) 311 end 312 313 @primary_key = column 314 if column[:keep_order] 315 columns << column 316 else 317 columns.unshift(column) 318 end 319 nil 320 end
class Sequel::Schema::CreateTableGenerator
Schema::CreateTableGenerator
is an internal class that the user is not expected to instantiate directly. Instances are created by Database#create_table
. It is used to specify table creation parameters. It takes a Database
object and a block of column/index/constraint specifications, and gives the Database
a table description, which the database uses to create a table.
Schema::CreateTableGenerator
has some methods but also includes method_missing
, allowing users to specify column type as a method instead of using the column method, which makes for a nicer DSL.
For more information on Sequel's support for schema modification, see the “Schema Modification” guide.
Constants
- GENERIC_TYPES
Classes specifying generic types that
Sequel
will convert to database-specific types.
Attributes
Column hashes created by this generator
Constraint hashes created by this generator
Index hashes created by this generator
Public Class Methods
Add a method for each of the given types that creates a column with that type as a constant. Types given should either already be constants/classes or a capitalized string/symbol with the same name as a constant/class.
# File lib/sequel/database/schema_generator.rb 59 def self.add_type_method(*types) 60 types.each do |type| 61 case type 62 when Symbol, String 63 method = type 64 type = Object.const_get(type) 65 else 66 method = type.to_s 67 end 68 69 define_method(method){|name, opts=OPTS| column(name, type, opts)} 70 end 71 nil 72 end
Set the database in which to create the table, and evaluate the block in the context of this object.
# File lib/sequel/database/schema_generator.rb 34 def initialize(db, &block) 35 @db = db 36 @columns = [] 37 @indexes = [] 38 @constraints = [] 39 @primary_key = nil 40 instance_exec(&block) if block 41 end
Public Instance Methods
Add an unnamed constraint, specified by the given block or args:
check(num: 1..5) # CHECK num >= 1 AND num <= 5 check{num > 5} # CHECK num > 5
# File lib/sequel/database/schema_generator.rb 79 def check(*args, &block) 80 constraint(nil, *args, &block) 81 end
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.
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 154 def column(name, type, opts = OPTS) 155 columns << {:name => name, :type => type}.merge!(opts) 156 if index_opts = opts[:index] 157 index(name, index_opts.is_a?(Hash) ? index_opts : OPTS) 158 end 159 nil 160 end
Adds a named CHECK constraint (or unnamed if name is nil), with the given block or args. To provide options for the constraint, pass a hash as the first argument.
constraint(:blah, num: 1..5) # CONSTRAINT blah CHECK num >= 1 AND num <= 5 constraint({name: :blah, deferrable: true}, num: 1..5) # CONSTRAINT blah CHECK num >= 1 AND num <= 5 DEFERRABLE INITIALLY DEFERRED
If the first argument is a hash, the following options are supported:
Options:
- :name
-
The name of the CHECK constraint
- :deferrable
-
Whether the CHECK constraint should be marked DEFERRABLE.
PostgreSQL specific options:
- :not_valid
-
Whether the CHECK constraint should be marked NOT VALID.
# File lib/sequel/database/schema_generator.rb 179 def constraint(name, *args, &block) 180 opts = name.is_a?(Hash) ? name : {:name=>name} 181 constraints << opts.merge(:type=>:check, :check=>block || args) 182 nil 183 end
Dump this generator's columns to a string that could be evaled inside another instance to represent the same columns
# File lib/sequel/extensions/schema_dumper.rb 396 def dump_columns 397 strings = [] 398 cols = columns.dup 399 cols.each do |x| 400 x.delete(:on_delete) if x[:on_delete] == :no_action 401 x.delete(:on_update) if x[:on_update] == :no_action 402 end 403 if (pkn = primary_key_name) && !@primary_key[:keep_order] 404 cols.delete_if{|x| x[:name] == pkn} 405 pk = @primary_key.dup 406 pkname = pk.delete(:name) 407 @db.serial_primary_key_options.each{|k,v| pk.delete(k) if v == pk[k]} 408 strings << "primary_key #{pkname.inspect}#{opts_inspect(pk)}" 409 end 410 cols.each do |c| 411 c = c.dup 412 name = c.delete(:name) 413 strings << if table = c.delete(:table) 414 c.delete(:type) if c[:type] == Integer || c[:type] == 'integer' 415 "foreign_key #{name.inspect}, #{table.inspect}#{opts_inspect(c)}" 416 elsif pkn == name 417 @db.serial_primary_key_options.each{|k,v| c.delete(k) if v == c[k]} 418 "primary_key #{name.inspect}#{opts_inspect(c)}" 419 else 420 type = c.delete(:type) 421 opts = opts_inspect(c) 422 case type 423 when Class 424 "#{type.name} #{name.inspect}#{opts}" 425 when :Bignum 426 "Bignum #{name.inspect}#{opts}" 427 else 428 "column #{name.inspect}, #{type.inspect}#{opts}" 429 end 430 end 431 end 432 strings.join("\n") 433 end
Dump this generator's constraints to a string that could be evaled inside another instance to represent the same constraints
# File lib/sequel/extensions/schema_dumper.rb 437 def dump_constraints 438 cs = constraints.map do |c| 439 c = c.dup 440 type = c.delete(:type) 441 case type 442 when :check 443 raise(Error, "can't dump check/constraint specified with Proc") if c[:check].is_a?(Proc) 444 name = c.delete(:name) 445 if !name and c[:check].length == 1 and c[:check].first.is_a?(Hash) 446 "check #{c[:check].first.inspect[1...-1]}" 447 else 448 "#{name ? "constraint #{name.inspect}," : 'check'} #{c[:check].map(&:inspect).join(', ')}" 449 end 450 when :foreign_key 451 c.delete(:on_delete) if c[:on_delete] == :no_action 452 c.delete(:on_update) if c[:on_update] == :no_action 453 c.delete(:deferrable) unless c[:deferrable] 454 cols = c.delete(:columns) 455 table = c.delete(:table) 456 "#{type} #{cols.inspect}, #{table.inspect}#{opts_inspect(c)}" 457 else 458 cols = c.delete(:columns) 459 "#{type} #{cols.inspect}#{opts_inspect(c)}" 460 end 461 end 462 cs.join("\n") 463 end
Dump this generator's indexes to a string that could be evaled inside another instance to represent the same indexes. Options:
- :add_index
-
Use add_index instead of index, so the methods can be called outside of a generator but inside a migration. The value of this option should be the table name to use.
- :drop_index
-
Same as add_index, but create drop_index statements.
- :ignore_errors
-
Add the ignore_errors option to the outputted indexes
# File lib/sequel/extensions/schema_dumper.rb 472 def dump_indexes(options=OPTS) 473 is = indexes.map do |c| 474 c = c.dup 475 cols = c.delete(:columns) 476 if table = options[:add_index] || options[:drop_index] 477 "#{options[:drop_index] ? 'drop' : 'add'}_index #{table.inspect}, #{cols.inspect}#{', :ignore_errors=>true' if options[:ignore_errors]}#{opts_inspect(c)}" 478 else 479 "index #{cols.inspect}#{opts_inspect(c)}" 480 end 481 end 482 is = is.reverse if options[:drop_index] 483 is.join("\n") 484 end
Add a foreign key in the table that references another table. See column
for available options.
foreign_key(:artist_id) # artist_id INTEGER foreign_key(:artist_id, :artists) # artist_id INTEGER REFERENCES artists foreign_key(:artist_id, :artists, key: :id) # artist_id INTEGER REFERENCES artists(id) foreign_key(:artist_id, :artists, type: String) # artist_id varchar(255) REFERENCES artists(id)
Additional Options:
- :foreign_key_constraint_name
-
The name to give the foreign key constraint
If you want a foreign key constraint without adding a column (usually because it is a composite foreign key), you can provide an array of columns as the first argument, and you can provide the :name option to name the constraint:
foreign_key([:artist_name, :artist_location], :artists, name: :artist_fk) # ADD CONSTRAINT artist_fk FOREIGN KEY (artist_name, artist_location) REFERENCES artists
# File lib/sequel/database/schema_generator.rb 203 def foreign_key(name, table=nil, opts = OPTS) 204 opts = case table 205 when Hash 206 table.merge(opts) 207 when NilClass 208 opts 209 else 210 opts.merge(:table=>table) 211 end 212 return composite_foreign_key(name, opts) if name.is_a?(Array) 213 column(name, Integer, opts) 214 end
Add a full text index on the given columns.
PostgreSQL specific options:
- :index_type
-
Can be set to :gist to use a GIST index instead of the default GIN index.
- :language
-
Set a language to use for the index (default: simple).
Microsoft SQL
Server specific options:
- :key_index
-
The KEY INDEX to use for the full text index.
# File lib/sequel/database/schema_generator.rb 225 def full_text_index(columns, opts = OPTS) 226 index(columns, opts.merge(:type => :full_text)) 227 end
True if the generator includes the creation of a column with the given name.
# File lib/sequel/database/schema_generator.rb 230 def has_column?(name) 231 columns.any?{|c| c[:name] == name} 232 end
Add an index on the given column(s) with the given options. General options:
- :name
-
The name to use for the index. If not given, a default name based on the table and columns is used.
- :type
-
The type of index to use (only supported by some databases)
- :unique
-
Make the index unique, so duplicate values are not allowed.
- :where
-
Create a partial index (only supported by some databases)
PostgreSQL specific options:
- :concurrently
-
Create the index concurrently, so it doesn't block operations on the table while the index is being built.
- :opclass
-
Use a specific operator class in the index.
- :include
-
Include additional column values in the index, without actually indexing on those values (PostgreSQL 11+).
- :tablespace
-
Specify tablespace for index.
Microsoft SQL
Server specific options:
- :include
-
Include additional column values in the index, without actually indexing on those values.
index :name # CREATE INDEX table_name_index ON table (name) index [:artist_id, :name] # CREATE INDEX table_artist_id_name_index ON table (artist_id, name)
# File lib/sequel/database/schema_generator.rb 263 def index(columns, opts = OPTS) 264 indexes << {:columns => Array(columns)}.merge!(opts) 265 nil 266 end
Add a column with the given type, name, and opts. See column
for available options.
# File lib/sequel/database/schema_generator.rb 270 def method_missing(type, name = nil, opts = OPTS) 271 name ? column(name, type, opts) : super 272 end
Adds an autoincrementing primary key column or a primary key constraint. To just create a constraint, the first argument should be an array of column symbols specifying the primary key columns. To create an autoincrementing primary key column, a single symbol can be used. In both cases, an options hash can be used as the second argument.
If you want to create a primary key column that is not autoincrementing, you should not use this method. Instead, you should use the regular column
method with a primary_key: true
option.
If an array of column symbols is used, you can specify the :name option to name the constraint.
Options:
- :keep_order
-
For non-composite primary keys, respects the existing order of columns, overriding the default behavior of making the primary key the first column.
Examples:
primary_key(:id) primary_key(:id, type: :Bignum, keep_order: true) primary_key([:street_number, :house_number], name: :some constraint_name)
The name of the primary key for this generator, if it has a primary key.
# File lib/sequel/database/schema_generator.rb 323 def primary_key_name 324 @primary_key[:name] if @primary_key 325 end
This object responds to all methods.
# File lib/sequel/database/schema_generator.rb 275 def respond_to_missing?(meth, include_private) 276 true 277 end
Add a spatial index on the given columns.
# File lib/sequel/database/schema_generator.rb 328 def spatial_index(columns, opts = OPTS) 329 index(columns, opts.merge(:type => :spatial)) 330 end
Add a unique constraint on the given columns.
unique(:name) # UNIQUE (name)
Supports the same :deferrable option as column
. The :name option can be used to name the constraint.
# File lib/sequel/database/schema_generator.rb 338 def unique(columns, opts = OPTS) 339 constraints << {:type => :unique, :columns => Array(columns)}.merge!(opts) 340 nil 341 end
Private Instance Methods
Add a composite foreign key constraint
# File lib/sequel/database/schema_generator.rb 353 def composite_foreign_key(columns, opts) 354 constraints << {:type => :foreign_key, :columns => columns}.merge!(opts) 355 nil 356 end
Add a composite primary key constraint
# File lib/sequel/database/schema_generator.rb 346 def composite_primary_key(columns, *args) 347 opts = args.pop || OPTS 348 constraints << {:type => :primary_key, :columns => columns}.merge!(opts) 349 nil 350 end
Return a string that converts the given options into one suitable for literal ruby code, handling default values that don't default to a literal interpretation.
# File lib/sequel/extensions/schema_dumper.rb 491 def opts_inspect(opts) 492 if opts[:default] 493 opts = opts.dup 494 de = Sequel.eval_inspect(opts.delete(:default)) 495 ", :default=>#{de}#{", #{opts.inspect[1...-1]}" if opts.length > 0}" 496 else 497 ", #{opts.inspect[1...-1]}" if opts.length > 0 498 end 499 end