Class Sequel::Schema::CreateTableGenerator
In: lib/sequel/database/schema_generator.rb
lib/sequel/extensions/schema_dumper.rb
Parent: Object

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.

Methods

Constants

GENERIC_TYPES = %w'String Integer Float Numeric BigDecimal Date DateTime Time File TrueClass FalseClass'.freeze   Classes specifying generic types that Sequel will convert to database-specific types.

Attributes

columns  [R]  Column hashes created by this generator
constraints  [R]  Constraint hashes created by this generator
indexes  [R]  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.

[Source]

    # File lib/sequel/database/schema_generator.rb, line 60
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={}| 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.

[Source]

    # File lib/sequel/database/schema_generator.rb, line 34
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

Use custom Bignum method to use :Bignum instead of Bignum class, to work correctly in cases where Bignum is the same as Integer.

[Source]

    # File lib/sequel/database/schema_generator.rb, line 46
46:       def Bignum(name, opts=OPTS)
47:         column(name, :Bignum, opts)
48:       end

Use custom Fixnum method to use Integer instead of Fixnum class, to avoid warnings on ruby 2.4+.

[Source]

    # File lib/sequel/database/schema_generator.rb, line 52
52:       def Fixnum(name, opts=OPTS)
53:         column(name, Integer, opts)
54:       end

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

[Source]

    # File lib/sequel/database/schema_generator.rb, line 80
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.
: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
: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

[Source]

     # File lib/sequel/database/schema_generator.rb, line 133
133:       def column(name, type, opts = OPTS)
134:         columns << {:name => name, :type => type}.merge!(opts)
135:         if index_opts = opts[:index]
136:           index(name, index_opts.is_a?(Hash) ? index_opts : {})
137:         end
138:         nil
139:       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

[Source]

     # File lib/sequel/database/schema_generator.rb, line 149
149:       def constraint(name, *args, &block)
150:         opts = name.is_a?(Hash) ? name : {:name=>name}
151:         constraints << opts.merge(:type=>:check, :check=>block || args)
152:         nil
153:       end

Dump this generator‘s columns to a string that could be evaled inside another instance to represent the same columns

[Source]

     # File lib/sequel/extensions/schema_dumper.rb, line 393
393:       def dump_columns
394:         strings = []
395:         cols = columns.dup
396:         cols.each do |x|
397:           x.delete(:on_delete) if x[:on_delete] == :no_action
398:           x.delete(:on_update) if x[:on_update] == :no_action
399:         end
400:         if (pkn = primary_key_name) && !@primary_key[:keep_order]
401:           cols.delete_if{|x| x[:name] == pkn}
402:           pk = @primary_key.dup
403:           pkname = pk.delete(:name)
404:           @db.serial_primary_key_options.each{|k,v| pk.delete(k) if v == pk[k]}
405:           strings << "primary_key #{pkname.inspect}#{opts_inspect(pk)}"
406:         end
407:         cols.each do |c|
408:           c = c.dup
409:           name = c.delete(:name)
410:           strings << if table = c.delete(:table)
411:             c.delete(:type) if c[:type] == Integer || c[:type] == 'integer'
412:             "foreign_key #{name.inspect}, #{table.inspect}#{opts_inspect(c)}"
413:           elsif pkn == name
414:             @db.serial_primary_key_options.each{|k,v| c.delete(k) if v == c[k]}
415:             "primary_key #{name.inspect}#{opts_inspect(c)}"
416:           else
417:             type = c.delete(:type)
418:             opts = opts_inspect(c)
419:             case type
420:             when Class
421:               "#{type.name} #{name.inspect}#{opts}"
422:             when :Bignum
423:               "Bignum #{name.inspect}#{opts}"
424:             else
425:               "column #{name.inspect}, #{type.inspect}#{opts}"
426:             end
427:           end
428:         end
429:         strings.join("\n")
430:       end

Dump this generator‘s constraints to a string that could be evaled inside another instance to represent the same constraints

[Source]

     # File lib/sequel/extensions/schema_dumper.rb, line 434
434:       def dump_constraints
435:         cs = constraints.map do |c|
436:           c = c.dup
437:           type = c.delete(:type)
438:           case type
439:           when :check
440:             raise(Error, "can't dump check/constraint specified with Proc") if c[:check].is_a?(Proc)
441:             name = c.delete(:name)
442:             if !name and c[:check].length == 1 and c[:check].first.is_a?(Hash)
443:               "check #{c[:check].first.inspect[1...-1]}"
444:             else
445:               "#{name ? "constraint #{name.inspect}," : 'check'} #{c[:check].map(&:inspect).join(', ')}"
446:             end
447:           when :foreign_key
448:             c.delete(:on_delete) if c[:on_delete] == :no_action
449:             c.delete(:on_update) if c[:on_update] == :no_action
450:             c.delete(:deferrable) unless c[:deferrable]
451:             cols = c.delete(:columns)
452:             table = c.delete(:table)
453:             "#{type} #{cols.inspect}, #{table.inspect}#{opts_inspect(c)}"
454:           else
455:             cols = c.delete(:columns)
456:             "#{type} #{cols.inspect}#{opts_inspect(c)}"
457:           end
458:         end
459:         cs.join("\n")
460:       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

[Source]

     # File lib/sequel/extensions/schema_dumper.rb, line 469
469:       def dump_indexes(options=OPTS)
470:         is = indexes.map do |c|
471:           c = c.dup
472:           cols = c.delete(:columns)
473:           if table = options[:add_index] || options[:drop_index]
474:             "#{options[:drop_index] ? 'drop' : 'add'}_index #{table.inspect}, #{cols.inspect}#{', :ignore_errors=>true' if options[:ignore_errors]}#{opts_inspect(c)}"
475:           else
476:             "index #{cols.inspect}#{opts_inspect(c)}"
477:           end
478:         end
479:         is = is.reverse if options[:drop_index]
480:         is.join("\n")
481:       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

[Source]

     # File lib/sequel/database/schema_generator.rb, line 173
173:       def foreign_key(name, table=nil, opts = OPTS)
174:         opts = case table
175:         when Hash
176:           table.merge(opts)
177:         when NilClass
178:           opts
179:         else
180:           opts.merge(:table=>table)
181:         end
182:         return composite_foreign_key(name, opts) if name.is_a?(Array)
183:         column(name, Integer, opts)
184:       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.

[Source]

     # File lib/sequel/database/schema_generator.rb, line 195
195:       def full_text_index(columns, opts = OPTS)
196:         index(columns, opts.merge(:type => :full_text))
197:       end

True if the generator includes the creation of a column with the given name.

[Source]

     # File lib/sequel/database/schema_generator.rb, line 200
200:       def has_column?(name)
201:         columns.any?{|c| c[:name] == name}
202:       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.

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)

[Source]

     # File lib/sequel/database/schema_generator.rb, line 230
230:       def index(columns, opts = OPTS)
231:         indexes << {:columns => Array(columns)}.merge!(opts)
232:         nil
233:       end

Add a column with the given type, name, and opts. See column for available options.

[Source]

     # File lib/sequel/database/schema_generator.rb, line 237
237:       def method_missing(type, name = nil, opts = OPTS)
238:         name ? column(name, type, opts) : super
239:       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, Bigint)
  primary_key(:id, Bigint, keep_order: true)
  primary_key([:street_number, :house_number], name: :some constraint_name)

[Source]

     # File lib/sequel/database/schema_generator.rb, line 269
269:       def primary_key(name, *args)
270:         return composite_primary_key(name, *args) if name.is_a?(Array)
271:         column = @db.serial_primary_key_options.merge({:name => name})
272:         
273:         if opts = args.pop
274:           opts = {:type => opts} unless opts.is_a?(Hash)
275:           if type = args.pop
276:             opts = opts.merge(:type => type)
277:           end
278:           column.merge!(opts)
279:         end
280: 
281:         @primary_key = column
282:         if column[:keep_order]
283:           columns << column
284:         else
285:           columns.unshift(column)
286:         end
287:         nil
288:       end

The name of the primary key for this generator, if it has a primary key.

[Source]

     # File lib/sequel/database/schema_generator.rb, line 291
291:       def primary_key_name
292:         @primary_key[:name] if @primary_key
293:       end

This object responds to all methods.

[Source]

     # File lib/sequel/database/schema_generator.rb, line 242
242:       def respond_to_missing?(meth, include_private)
243:         true
244:       end

Add a spatial index on the given columns.

[Source]

     # File lib/sequel/database/schema_generator.rb, line 296
296:       def spatial_index(columns, opts = OPTS)
297:         index(columns, opts.merge(:type => :spatial))
298:       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.

[Source]

     # File lib/sequel/database/schema_generator.rb, line 306
306:       def unique(columns, opts = OPTS)
307:         constraints << {:type => :unique, :columns => Array(columns)}.merge!(opts)
308:         nil
309:       end

[Validate]