# File lib/sequel/database/schema_generator.rb 307 def primary_key(name, *args) 308 return composite_primary_key(name, *args) if name.is_a?(Array) 309 column = @db.serial_primary_key_options.merge({:name => name}) 310 311 if opts = args.pop 312 opts = {:type => opts} unless opts.is_a?(Hash) 313 if type = args.pop 314 opts = opts.merge(:type => type) 315 end 316 column.merge!(opts) 317 end 318 319 @primary_key = column 320 if column[:keep_order] 321 columns << column 322 else 323 columns.unshift(column) 324 end 325 nil 326 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 407 def dump_columns 408 strings = [] 409 cols = columns.dup 410 cols.each do |x| 411 x.delete(:on_delete) if x[:on_delete] == :no_action 412 x.delete(:on_update) if x[:on_update] == :no_action 413 end 414 if (pkn = primary_key_name) && !@primary_key[:keep_order] 415 cols.delete_if{|x| x[:name] == pkn} 416 pk = @primary_key.dup 417 pkname = pk.delete(:name) 418 @db.serial_primary_key_options.each{|k,v| pk.delete(k) if v == pk[k]} 419 strings << "primary_key #{pkname.inspect}#{opts_inspect(pk)}" 420 end 421 cols.each do |c| 422 c = c.dup 423 name = c.delete(:name) 424 strings << if table = c.delete(:table) 425 c.delete(:type) if c[:type] == Integer || c[:type] == 'integer' 426 "foreign_key #{name.inspect}, #{table.inspect}#{opts_inspect(c)}" 427 elsif pkn == name 428 @db.serial_primary_key_options.each{|k,v| c.delete(k) if v == c[k]} 429 "primary_key #{name.inspect}#{opts_inspect(c)}" 430 else 431 type = c.delete(:type) 432 opts = opts_inspect(c) 433 case type 434 when Class 435 "#{type.name} #{name.inspect}#{opts}" 436 when :Bignum 437 "Bignum #{name.inspect}#{opts}" 438 else 439 "column #{name.inspect}, #{type.inspect}#{opts}" 440 end 441 end 442 end 443 strings.join("\n") 444 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 448 def dump_constraints 449 cs = constraints.map do |c| 450 c = c.dup 451 type = c.delete(:type) 452 case type 453 when :check 454 raise(Error, "can't dump check/constraint specified with Proc") if c[:check].is_a?(Proc) 455 name = c.delete(:name) 456 if !name and c[:check].length == 1 and c[:check].first.is_a?(Hash) 457 "check #{c[:check].first.inspect[1...-1]}" 458 else 459 "#{name ? "constraint #{name.inspect}," : 'check'} #{c[:check].map(&:inspect).join(', ')}" 460 end 461 when :foreign_key 462 c.delete(:on_delete) if c[:on_delete] == :no_action 463 c.delete(:on_update) if c[:on_update] == :no_action 464 c.delete(:deferrable) unless c[:deferrable] 465 cols = c.delete(:columns) 466 table = c.delete(:table) 467 "#{type} #{cols.inspect}, #{table.inspect}#{opts_inspect(c)}" 468 else 469 cols = c.delete(:columns) 470 "#{type} #{cols.inspect}#{opts_inspect(c)}" 471 end 472 end 473 cs.join("\n") 474 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 483 def dump_indexes(options=OPTS) 484 is = indexes.map do |c| 485 c = c.dup 486 cols = c.delete(:columns) 487 if table = options[:add_index] || options[:drop_index] 488 "#{options[:drop_index] ? 'drop' : 'add'}_index #{table.inspect}, #{cols.inspect}#{', :ignore_errors=>true' if options[:ignore_errors]}#{opts_inspect(c)}" 489 else 490 "index #{cols.inspect}#{opts_inspect(c)}" 491 end 492 end 493 is = is.reverse if options[:drop_index] 494 is.join("\n") 495 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. See index
for additional options.
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).
# File lib/sequel/database/schema_generator.rb 223 def full_text_index(columns, opts = OPTS) 224 index(columns, opts.merge(:type => :full_text)) 225 end
True if the generator includes the creation of a column with the given name.
# File lib/sequel/database/schema_generator.rb 228 def has_column?(name) 229 columns.any?{|c| c[:name] == name} 230 end
Add an index on the given column(s) with the given options. Examples:
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) index [:artist_id, :name], name: :foo # CREATE INDEX foo ON table (artist_id, name)
General options:
- :include
-
Include additional column values in the index, without actually indexing on those values (only supported by some databases).
- :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, :full_text and :spatial values are handled specially).
- :unique
-
Make the index unique, so duplicate values are not allowed.
- :where
-
A filter expression, used to 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.
- :if_not_exists
-
Only create the index if an index of the same name doesn't already exist.
- :opclass
-
Set an opclass to use for all columns (per-column opclasses require custom
SQL
). - :tablespace
-
Specify tablespace for index.
Microsoft SQL
Server specific options:
- :key_index
-
Sets the KEY INDEX to the given value.
# File lib/sequel/database/schema_generator.rb 269 def index(columns, opts = OPTS) 270 indexes << {:columns => Array(columns)}.merge!(opts) 271 nil 272 end
Add a column with the given type, name, and opts. See column
for available options.
# File lib/sequel/database/schema_generator.rb 276 def method_missing(type, name = nil, opts = OPTS) 277 name ? column(name, type, opts) : super 278 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 329 def primary_key_name 330 @primary_key[:name] if @primary_key 331 end
This object responds to all methods.
# File lib/sequel/database/schema_generator.rb 281 def respond_to_missing?(meth, include_private) 282 true 283 end
Add a spatial index on the given columns. See index
for additional options.
# File lib/sequel/database/schema_generator.rb 335 def spatial_index(columns, opts = OPTS) 336 index(columns, opts.merge(:type => :spatial)) 337 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 345 def unique(columns, opts = OPTS) 346 constraints << {:type => :unique, :columns => Array(columns)}.merge!(opts) 347 nil 348 end
Private Instance Methods
Add a composite foreign key constraint
# File lib/sequel/database/schema_generator.rb 360 def composite_foreign_key(columns, opts) 361 constraints << {:type => :foreign_key, :columns => columns}.merge!(opts) 362 nil 363 end
Add a composite primary key constraint
# File lib/sequel/database/schema_generator.rb 353 def composite_primary_key(columns, *args) 354 opts = args.pop || OPTS 355 constraints << {:type => :primary_key, :columns => columns}.merge!(opts) 356 nil 357 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 502 def opts_inspect(opts) 503 if opts[:default] 504 opts = opts.dup 505 de = Sequel.eval_inspect(opts.delete(:default)) 506 ", :default=>#{de}#{", #{opts.inspect[1...-1]}" if opts.length > 0}" 507 else 508 ", #{opts.inspect[1...-1]}" if opts.length > 0 509 end 510 end