# File lib/sequel/database/schema_generator.rb 287 def primary_key(name, *args) 288 return composite_primary_key(name, *args) if name.is_a?(Array) 289 column = @db.serial_primary_key_options.merge({:name => name}) 290 291 if opts = args.pop 292 opts = {:type => opts} unless opts.is_a?(Hash) 293 if type = args.pop 294 opts = opts.merge(:type => type) 295 end 296 column.merge!(opts) 297 end 298 299 @primary_key = column 300 if column[:keep_order] 301 columns << column 302 else 303 columns.unshift(column) 304 end 305 nil 306 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 60 def self.add_type_method(*types) 61 types.each do |type| 62 case type 63 when Symbol, String 64 method = type 65 type = Object.const_get(type) 66 else 67 method = type.to_s 68 end 69 70 define_method(method){|name, opts=OPTS| column(name, type, opts)} 71 end 72 nil 73 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 @columns.unshift(@primary_key) if @primary_key && !has_column?(primary_key_name) 42 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 80 def check(*args, &block) 81 constraint(nil, *args, &block) 82 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 have a single, nonautoincrementing 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.
# File lib/sequel/database/schema_generator.rb 149 def column(name, type, opts = OPTS) 150 columns << {:name => name, :type => type}.merge!(opts) 151 if index_opts = opts[:index] 152 index(name, index_opts.is_a?(Hash) ? index_opts : OPTS) 153 end 154 nil 155 end
Adds a named 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
# File lib/sequel/database/schema_generator.rb 165 def constraint(name, *args, &block) 166 opts = name.is_a?(Hash) ? name : {:name=>name} 167 constraints << opts.merge(:type=>:check, :check=>block || args) 168 nil 169 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 390 def dump_columns 391 strings = [] 392 cols = columns.dup 393 cols.each do |x| 394 x.delete(:on_delete) if x[:on_delete] == :no_action 395 x.delete(:on_update) if x[:on_update] == :no_action 396 end 397 if (pkn = primary_key_name) && !@primary_key[:keep_order] 398 cols.delete_if{|x| x[:name] == pkn} 399 pk = @primary_key.dup 400 pkname = pk.delete(:name) 401 @db.serial_primary_key_options.each{|k,v| pk.delete(k) if v == pk[k]} 402 strings << "primary_key #{pkname.inspect}#{opts_inspect(pk)}" 403 end 404 cols.each do |c| 405 c = c.dup 406 name = c.delete(:name) 407 strings << if table = c.delete(:table) 408 c.delete(:type) if c[:type] == Integer || c[:type] == 'integer' 409 "foreign_key #{name.inspect}, #{table.inspect}#{opts_inspect(c)}" 410 elsif pkn == name 411 @db.serial_primary_key_options.each{|k,v| c.delete(k) if v == c[k]} 412 "primary_key #{name.inspect}#{opts_inspect(c)}" 413 else 414 type = c.delete(:type) 415 opts = opts_inspect(c) 416 case type 417 when Class 418 "#{type.name} #{name.inspect}#{opts}" 419 when :Bignum 420 "Bignum #{name.inspect}#{opts}" 421 else 422 "column #{name.inspect}, #{type.inspect}#{opts}" 423 end 424 end 425 end 426 strings.join("\n") 427 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 431 def dump_constraints 432 cs = constraints.map do |c| 433 c = c.dup 434 type = c.delete(:type) 435 case type 436 when :check 437 raise(Error, "can't dump check/constraint specified with Proc") if c[:check].is_a?(Proc) 438 name = c.delete(:name) 439 if !name and c[:check].length == 1 and c[:check].first.is_a?(Hash) 440 "check #{c[:check].first.inspect[1...-1]}" 441 else 442 "#{name ? "constraint #{name.inspect}," : 'check'} #{c[:check].map(&:inspect).join(', ')}" 443 end 444 when :foreign_key 445 c.delete(:on_delete) if c[:on_delete] == :no_action 446 c.delete(:on_update) if c[:on_update] == :no_action 447 c.delete(:deferrable) unless c[:deferrable] 448 cols = c.delete(:columns) 449 table = c.delete(:table) 450 "#{type} #{cols.inspect}, #{table.inspect}#{opts_inspect(c)}" 451 else 452 cols = c.delete(:columns) 453 "#{type} #{cols.inspect}#{opts_inspect(c)}" 454 end 455 end 456 cs.join("\n") 457 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 466 def dump_indexes(options=OPTS) 467 is = indexes.map do |c| 468 c = c.dup 469 cols = c.delete(:columns) 470 if table = options[:add_index] || options[:drop_index] 471 "#{options[:drop_index] ? 'drop' : 'add'}_index #{table.inspect}, #{cols.inspect}#{', :ignore_errors=>true' if options[:ignore_errors]}#{opts_inspect(c)}" 472 else 473 "index #{cols.inspect}#{opts_inspect(c)}" 474 end 475 end 476 is = is.reverse if options[:drop_index] 477 is.join("\n") 478 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 189 def foreign_key(name, table=nil, opts = OPTS) 190 opts = case table 191 when Hash 192 table.merge(opts) 193 when NilClass 194 opts 195 else 196 opts.merge(:table=>table) 197 end 198 return composite_foreign_key(name, opts) if name.is_a?(Array) 199 column(name, Integer, opts) 200 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 211 def full_text_index(columns, opts = OPTS) 212 index(columns, opts.merge(:type => :full_text)) 213 end
True if the generator includes the creation of a column with the given name.
# File lib/sequel/database/schema_generator.rb 216 def has_column?(name) 217 columns.any?{|c| c[:name] == name} 218 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 249 def index(columns, opts = OPTS) 250 indexes << {:columns => Array(columns)}.merge!(opts) 251 nil 252 end
Add a column with the given type, name, and opts. See column
for available options.
# File lib/sequel/database/schema_generator.rb 256 def method_missing(type, name = nil, opts = OPTS) 257 name ? column(name, type, opts) : super 258 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 309 def primary_key_name 310 @primary_key[:name] if @primary_key 311 end
This object responds to all methods.
# File lib/sequel/database/schema_generator.rb 261 def respond_to_missing?(meth, include_private) 262 true 263 end
Add a spatial index on the given columns.
# File lib/sequel/database/schema_generator.rb 314 def spatial_index(columns, opts = OPTS) 315 index(columns, opts.merge(:type => :spatial)) 316 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 324 def unique(columns, opts = OPTS) 325 constraints << {:type => :unique, :columns => Array(columns)}.merge!(opts) 326 nil 327 end
Private Instance Methods
Add a composite foreign key constraint
# File lib/sequel/database/schema_generator.rb 339 def composite_foreign_key(columns, opts) 340 constraints << {:type => :foreign_key, :columns => columns}.merge!(opts) 341 nil 342 end
Add a composite primary key constraint
# File lib/sequel/database/schema_generator.rb 332 def composite_primary_key(columns, *args) 333 opts = args.pop || OPTS 334 constraints << {:type => :primary_key, :columns => columns}.merge!(opts) 335 nil 336 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 485 def opts_inspect(opts) 486 if opts[:default] 487 opts = opts.dup 488 de = Sequel.eval_inspect(opts.delete(:default)) 489 ", :default=>#{de}#{", #{opts.inspect[1...-1]}" if opts.length > 0}" 490 else 491 ", #{opts.inspect[1...-1]}" if opts.length > 0 492 end 493 end