# File lib/sequel/database/schema_generator.rb, line 269 def primary_key(name, *args) return composite_primary_key(name, *args) if name.is_a?(Array) column = @db.serial_primary_key_options.merge({:name => name}) if opts = args.pop opts = {:type => opts} unless opts.is_a?(Hash) if type = args.pop opts = opts.merge(:type => type) end column.merge!(opts) end @primary_key = column if column[:keep_order] columns << column else columns.unshift(column) end nil end
class Sequel::Schema::CreateTableGenerator
Schema::CreateTableGenerator is an internal class that the user is not expected to instantiate directly. Instances are created by Sequel::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, line 60 def self.add_type_method(*types) types.each do |type| case type when Symbol, String method = type type = Object.const_get(type) else method = type.to_s end define_method(method){|name, opts={}| column(name, type, opts)} end nil 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, line 34 def initialize(db, &block) @db = db @columns = [] @indexes = [] @constraints = [] @primary_key = nil instance_exec(&block) if block @columns.unshift(@primary_key) if @primary_key && !has_column?(primary_key_name) 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, line 80 def check(*args, &block) constraint(nil, *args, &block) 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
# File lib/sequel/database/schema_generator.rb, line 133 def column(name, type, opts = OPTS) columns << {:name => name, :type => type}.merge!(opts) if index_opts = opts[:index] index(name, index_opts.is_a?(Hash) ? index_opts : {}) end nil 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, line 149 def constraint(name, *args, &block) opts = name.is_a?(Hash) ? name : {:name=>name} constraints << opts.merge(:type=>:check, :check=>block || args) nil 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, line 390 def dump_columns strings = [] cols = columns.dup cols.each do |x| x.delete(:on_delete) if x[:on_delete] == :no_action x.delete(:on_update) if x[:on_update] == :no_action end if (pkn = primary_key_name) && !@primary_key[:keep_order] cols.delete_if{|x| x[:name] == pkn} pk = @primary_key.dup pkname = pk.delete(:name) @db.serial_primary_key_options.each{|k,v| pk.delete(k) if v == pk[k]} strings << "primary_key #{pkname.inspect}#{opts_inspect(pk)}" end cols.each do |c| c = c.dup name = c.delete(:name) strings << if table = c.delete(:table) c.delete(:type) if c[:type] == Integer || c[:type] == 'integer' "foreign_key #{name.inspect}, #{table.inspect}#{opts_inspect(c)}" elsif pkn == name @db.serial_primary_key_options.each{|k,v| c.delete(k) if v == c[k]} "primary_key #{name.inspect}#{opts_inspect(c)}" else type = c.delete(:type) opts = opts_inspect(c) case type when Class "#{type.name} #{name.inspect}#{opts}" when :Bignum "Bignum #{name.inspect}#{opts}" else "column #{name.inspect}, #{type.inspect}#{opts}" end end end strings.join("\n") 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, line 431 def dump_constraints cs = constraints.map do |c| c = c.dup type = c.delete(:type) case type when :check raise(Error, "can't dump check/constraint specified with Proc") if c[:check].is_a?(Proc) name = c.delete(:name) if !name and c[:check].length == 1 and c[:check].first.is_a?(Hash) "check #{c[:check].first.inspect[1...-1]}" else "#{name ? "constraint #{name.inspect}," : 'check'} #{c[:check].map(&:inspect).join(', ')}" end when :foreign_key c.delete(:on_delete) if c[:on_delete] == :no_action c.delete(:on_update) if c[:on_update] == :no_action c.delete(:deferrable) unless c[:deferrable] cols = c.delete(:columns) table = c.delete(:table) "#{type} #{cols.inspect}, #{table.inspect}#{opts_inspect(c)}" else cols = c.delete(:columns) "#{type} #{cols.inspect}#{opts_inspect(c)}" end end cs.join("\n") 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, line 466 def dump_indexes(options=OPTS) is = indexes.map do |c| c = c.dup cols = c.delete(:columns) if table = options[:add_index] || options[:drop_index] "#{options[:drop_index] ? 'drop' : 'add'}_index #{table.inspect}, #{cols.inspect}#{', :ignore_errors=>true' if options[:ignore_errors]}#{opts_inspect(c)}" else "index #{cols.inspect}#{opts_inspect(c)}" end end is = is.reverse if options[:drop_index] is.join("\n") 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, line 173 def foreign_key(name, table=nil, opts = OPTS) opts = case table when Hash table.merge(opts) when NilClass opts else opts.merge(:table=>table) end return composite_foreign_key(name, opts) if name.is_a?(Array) column(name, Integer, opts) 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, line 195 def full_text_index(columns, opts = OPTS) index(columns, opts.merge(:type => :full_text)) end
True if the generator includes the creation of a column with the given name.
# File lib/sequel/database/schema_generator.rb, line 200 def has_column?(name) columns.any?{|c| c[:name] == name} 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)
# File lib/sequel/database/schema_generator.rb, line 230 def index(columns, opts = OPTS) indexes << {:columns => Array(columns)}.merge!(opts) nil end
Add a column with the given type, name, and opts. See column
for available options.
# File lib/sequel/database/schema_generator.rb, line 237 def method_missing(type, name = nil, opts = OPTS) name ? column(name, type, opts) : super 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)
The name of the primary key for this generator, if it has a primary key.
# File lib/sequel/database/schema_generator.rb, line 291 def primary_key_name @primary_key[:name] if @primary_key end
This object responds to all methods.
# File lib/sequel/database/schema_generator.rb, line 242 def respond_to_missing?(meth, include_private) true end
Add a spatial index on the given columns.
# File lib/sequel/database/schema_generator.rb, line 296 def spatial_index(columns, opts = OPTS) index(columns, opts.merge(:type => :spatial)) 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, line 306 def unique(columns, opts = OPTS) constraints << {:type => :unique, :columns => Array(columns)}.merge!(opts) nil end
Private Instance Methods
Add a composite foreign key constraint
# File lib/sequel/database/schema_generator.rb, line 321 def composite_foreign_key(columns, opts) constraints << {:type => :foreign_key, :columns => columns}.merge!(opts) nil end
Add a composite primary key constraint
# File lib/sequel/database/schema_generator.rb, line 314 def composite_primary_key(columns, *args) opts = args.pop || {} constraints << {:type => :primary_key, :columns => columns}.merge!(opts) nil 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, line 485 def opts_inspect(opts) if opts[:default] opts = opts.dup de = Sequel.eval_inspect(opts.delete(:default)) ", :default=>#{de}#{", #{opts.inspect[1...-1]}" if opts.length > 0}" else ", #{opts.inspect[1...-1]}" if opts.length > 0 end end