# File lib/sequel/database/schema_generator.rb 286 def primary_key(name, *args) 287 return composite_primary_key(name, *args) if name.is_a?(Array) 288 column = @db.serial_primary_key_options.merge({:name => name}) 289 290 if opts = args.pop 291 opts = {:type => opts} unless opts.is_a?(Hash) 292 if type = args.pop 293 opts = opts.merge(:type => type) 294 end 295 column.merge!(opts) 296 end 297 298 @primary_key = column 299 if column[:keep_order] 300 columns << column 301 else 302 columns.unshift(column) 303 end 304 nil 305 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.
# File lib/sequel/database/schema_generator.rb 148 def column(name, type, opts = OPTS) 149 columns << {:name => name, :type => type}.merge!(opts) 150 if index_opts = opts[:index] 151 index(name, index_opts.is_a?(Hash) ? index_opts : OPTS) 152 end 153 nil 154 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 164 def constraint(name, *args, &block) 165 opts = name.is_a?(Hash) ? name : {:name=>name} 166 constraints << opts.merge(:type=>:check, :check=>block || args) 167 nil 168 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 188 def foreign_key(name, table=nil, opts = OPTS) 189 opts = case table 190 when Hash 191 table.merge(opts) 192 when NilClass 193 opts 194 else 195 opts.merge(:table=>table) 196 end 197 return composite_foreign_key(name, opts) if name.is_a?(Array) 198 column(name, Integer, opts) 199 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 210 def full_text_index(columns, opts = OPTS) 211 index(columns, opts.merge(:type => :full_text)) 212 end
True if the generator includes the creation of a column with the given name.
# File lib/sequel/database/schema_generator.rb 215 def has_column?(name) 216 columns.any?{|c| c[:name] == name} 217 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 248 def index(columns, opts = OPTS) 249 indexes << {:columns => Array(columns)}.merge!(opts) 250 nil 251 end
Add a column with the given type, name, and opts. See column
for available options.
# File lib/sequel/database/schema_generator.rb 255 def method_missing(type, name = nil, opts = OPTS) 256 name ? column(name, type, opts) : super 257 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 308 def primary_key_name 309 @primary_key[:name] if @primary_key 310 end
This object responds to all methods.
# File lib/sequel/database/schema_generator.rb 260 def respond_to_missing?(meth, include_private) 261 true 262 end
Add a spatial index on the given columns.
# File lib/sequel/database/schema_generator.rb 313 def spatial_index(columns, opts = OPTS) 314 index(columns, opts.merge(:type => :spatial)) 315 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 323 def unique(columns, opts = OPTS) 324 constraints << {:type => :unique, :columns => Array(columns)}.merge!(opts) 325 nil 326 end
Private Instance Methods
Add a composite foreign key constraint
# File lib/sequel/database/schema_generator.rb 338 def composite_foreign_key(columns, opts) 339 constraints << {:type => :foreign_key, :columns => columns}.merge!(opts) 340 nil 341 end
Add a composite primary key constraint
# File lib/sequel/database/schema_generator.rb 331 def composite_primary_key(columns, *args) 332 opts = args.pop || OPTS 333 constraints << {:type => :primary_key, :columns => columns}.merge!(opts) 334 nil 335 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