module Sequel::Model::ClassMethods

Class methods for Sequel::Model that implement basic model functionality.

All of the following methods have class methods created that send the method to the model’s dataset: all, any?, as_hash, as_set, avg, count, cross_join, distinct, each, each_server, empty?, except, exclude, exclude_having, fetch_rows, filter, first, first!, for_update, from, from_self, full_join, full_outer_join, get, graph, grep, group, group_and_count, group_append, group_by, having, import, inner_join, insert, intersect, invert, join, join_table, last, left_join, left_outer_join, limit, lock_style, map, max, min, multi_insert, naked, natural_full_join, natural_join, natural_left_join, natural_right_join, offset, order, order_append, order_by, order_more, order_prepend, paged_each, qualify, reverse, reverse_order, right_join, right_outer_join, select, select_all, select_append, select_group, select_hash, select_hash_groups, select_map, select_more, select_order_map, select_prepend, select_set, server, single_record, single_record!, single_value, single_value!, sum, to_hash, to_hash_groups, truncate, unfiltered, ungraphed, ungrouped, union, unlimited, unordered, where, where_all, where_each, where_single_value, with, with_recursive, with_sql

Attributes

Whether to cache the anonymous models created by Sequel::Model(), true by default. This is required for reloading them correctly (avoiding the superclass mismatch).

dataset_method_modules [R]

Array of modules that extend this model’s dataset. Stored so that if the model’s dataset is changed, it will be extended with all of these modules.

dataset_module_class [R]

The Module subclass to use for dataset_module blocks.

default_set_fields_options [RW]

The default options to use for Model#set_fields. These are merged with the options given to set_fields.

fast_instance_delete_sql [R]

SQL string fragment used for faster DELETE statement creation when deleting/destroying model instances, or nil if the optimization should not be used. For internal use only.

fast_pk_lookup_sql [R]

SQL string fragment used for faster lookups by primary key, or nil if the optimization should not be used. For internal use only.

instance_dataset [R]

The dataset that instance datasets (this) are based on. Generally a naked version of the model’s dataset limited to one row. For internal use only.

plugins [R]

Array of plugin modules loaded by this class

Sequel::Model.plugins
# => [Sequel::Model, Sequel::Model::Associations]

primary_key [R]

The primary key for the class. Sequel can determine this automatically for many databases, but not all, so you may need to set it manually. If not determined automatically, the default is :id.

raise_on_save_failure [RW]

Whether to raise an error instead of returning nil on a failure to save/create/save_changes/update/destroy due to a validation failure or a before_* hook returning false (default: true).

raise_on_typecast_failure [RW]

Whether to raise an error when unable to typecast data for a column (default: false). This should be set to true if you want to have model setter methods raise errors if the argument cannot be typecast properly.

require_modification [RW]

Whether to raise an error if an UPDATE or DELETE query related to a model instance does not modify exactly 1 row. If set to false, Sequel will not check the number of rows modified (default: true).

require_valid_table [RW]

If true (the default), requires that all models have valid tables, raising exceptions if creating a model without a valid table backing it. Setting this to false will allow the creation of model classes where the underlying table doesn’t exist.

shape_friendly [R]

Whether the model uses a shape friendly design (initializing all potentially used instance variables to nil).

simple_pk [R]

Should be the literal primary key column name if this Model’s table has a simple primary key, or nil if the model has a compound primary key or no primary key.

simple_table [R]

Should be the literal table name if this Model’s dataset is a simple table (no select, order, join, etc.), or nil otherwise. This and simple_pk are used for an optimization in Model[].

strict_param_setting [RW]

Whether mass assigning via .create/.new/#set/#update should raise an error if an invalid key is used. A key is invalid if no setter method exists for that key or the access to the setter method is restricted (e.g. due to it being a primary key field). If set to false, silently skip any key where the setter method doesn’t exist or access to it is restricted.

typecast_empty_string_to_nil [RW]

Whether to typecast the empty string (”) to nil for columns that are not string or blob. In most cases the empty string would be the way to specify a NULL SQL value in string form (nil.to_s == ”), and an empty string would not usually be typecast correctly for other types, so the default is true.

typecast_on_assignment [RW]

Whether to typecast attribute values on assignment (default: true). If set to false, no typecasting is done, so it will be left up to the database to typecast the value correctly.

use_transactions [RW]

Whether to use a transaction by default when saving/deleting records (default: true). If you are sending database queries in before_* or after_* hooks, you shouldn’t change the default setting without a good reason.

Public Instance Methods

[] (*args)

Source

    # File lib/sequel/model/base.rb
218 def [](*args)
219   args = args.first if args.size <= 1
220   args.is_a?(Hash) ? first(args) : (primary_key_lookup(args) unless args.nil?)
221 end

Returns the first record from the database matching the conditions. If a hash is given, it is used as the conditions. If another object is given, it finds the first record whose primary key(s) match the given argument(s). If no object is returned by the dataset, returns nil.

Artist[1] # SELECT * FROM artists WHERE id = 1
# => #<Artist {:id=>1, ...}>

Artist[name: 'Bob'] # SELECT * FROM artists WHERE (name = 'Bob') LIMIT 1
# => #<Artist {:name=>'Bob', ...}>

Model (source)

Source

    # File lib/sequel/model/base.rb
185 def Model(source)
186   if cache_anonymous_models
187     cache = Sequel.synchronize{@Model_cache ||= {}}
188     if klass = Sequel.synchronize{cache[source]}
189       return klass
190     end
191   end
192 
193   klass = Sequel.set_temp_name(Class.new(self)){"Sequel::_Model(#{source.inspect})"}
194 
195   if source.is_a?(::Sequel::Database)
196     klass.db = source
197   else
198     klass.set_dataset(source)
199   end
200 
201   if cache_anonymous_models
202     Sequel.synchronize{cache[source] = klass}
203   end
204 
205   klass
206 end

Lets you create a Model subclass with its dataset already set. source should be an instance of one of the following classes:

Database: Sets the database for this model to source. Generally only useful when subclassing directly from the returned class, where the name of the subclass sets the table name (which is combined with the Database in source to create the dataset to use)
Dataset: Sets the dataset for this model to source.
other: Sets the table name for this model to source. The class will use the default database for model classes in order to create the dataset.

The purpose of this method is to set the dataset/database automatically for a model class, if the table name doesn’t match the default table name that Sequel would use.

When creating subclasses of Sequel::Model itself, this method is usually called on Sequel itself, using Sequel::Model(:something).

# Using a symbol
class Comment < Sequel::Model(:something)
  table_name # => :something
end

# Using a dataset
class Comment < Sequel::Model(DB1[:something])
  dataset # => DB1[:something]
end

# Using a database
class Comment < Sequel::Model(DB1)
  dataset # => DB1[:comments]
end

call (values)

Source

    # File lib/sequel/model/base.rb
227 def call(values)
228   allocate.initialize_from_db(values)
229 end

Initializes a model instance as an existing record. This constructor is used by Sequel to initialize model instances when fetching records. Requires that values be a hash where all keys are symbols. It probably should not be used by external code.

clear_setter_methods_cache ()

Source

    # File lib/sequel/model/base.rb
232 def clear_setter_methods_cache
233   @setter_methods = nil unless frozen?
234 end

Clear the setter_methods cache

columns ()

Source

    # File lib/sequel/model/base.rb
243 def columns
244   return @columns if @columns
245   return nil if frozen?
246   set_columns(dataset.naked.columns)
247 end

Returns the columns in the result set in their original order. Generally, this will use the columns determined via the database schema, but in certain cases (e.g. models that are based on a joined dataset) it will use Dataset#columns to find the columns.

Artist.columns
# => [:id, :name]

create (values = OPTS, &block)

Source

    # File lib/sequel/model/base.rb
257 def create(values = OPTS, &block)
258   new(values, &block).save
259 end

Creates instance using new with the given values and block, and saves it.

Artist.create(name: 'Bob')
# INSERT INTO artists (name) VALUES ('Bob')

Artist.create do |a|
  a.name = 'Jim'
end # INSERT INTO artists (name) VALUES ('Jim')

dataset ()

Source

    # File lib/sequel/model/base.rb
267 def dataset
268   @dataset || raise(Error, "No dataset associated with #{self}")
269 end

Returns the dataset associated with the Model class. Raises an Error if there is no associated dataset for this class. In most cases, you don’t need to call this directly, as Model proxies many dataset methods to the underlying dataset.

Artist.dataset.all # SELECT * FROM artists

dataset= (ds)

Source

    # File lib/sequel/model/base.rb
272 def dataset=(ds)
273   set_dataset(ds)
274 end

Alias of set_dataset

dataset_module (mod = nil, &block)

Source

    # File lib/sequel/model/base.rb
331 def dataset_module(mod = nil, &block)
332   if mod
333     raise Error, "can't provide both argument and block to Model.dataset_module" if block
334     dataset_extend(mod)
335     mod
336   else
337     @dataset_module ||= dataset_module_class.new(self)
338     @dataset_module.module_eval(&block) if block
339     dataset_extend(@dataset_module)
340     @dataset_module
341   end
342 end

Extend the dataset with a module, similar to adding a plugin with the methods defined in DatasetMethods. This is the recommended way to add methods to model datasets.

If given an argument, it should be a module, and is used to extend the underlying dataset. Otherwise an anonymous module is created, and if a block is given, it is module_evaled, allowing you do define dataset methods directly using the standard ruby def syntax. Returns the module given or the anonymous module created.

# Usage with existing module
Album.dataset_module Sequel::ColumnsIntrospection

# Usage with anonymous module
Album.dataset_module do
  def foo
    :bar
  end
end
Album.dataset.foo
# => :bar
Album.foo
# => :bar

Any anonymous modules created are actually instances of Sequel::Model::DatasetModule (a Module subclass), which allows you to call the subset method on them, which defines a dataset method that adds a filter. There are also a number of other methods with the same names as the dataset methods, which can use to define named dataset methods:

Album.dataset_module do
  where(:released, Sequel[:release_date] <= Sequel::CURRENT_DATE)
  order :by_release_date, :release_date
  select :for_select_options, :id, :name, :release_date
end
Album.released.sql
# => "SELECT * FROM artists WHERE (release_date <= CURRENT_DATE)"
Album.by_release_date.sql
# => "SELECT * FROM artists ORDER BY release_date"
Album.for_select_options.sql
# => "SELECT id, name, release_date FROM artists"
Album.released.by_release_date.for_select_options.sql
# => "SELECT id, name, release_date FROM artists WHERE (release_date <= CURRENT_DATE) ORDER BY release_date"

The following methods are supported: distinct, eager, exclude, exclude_having, grep, group, group_and_count, group_append, having, limit, offset, order, order_append, order_prepend, select, select_all, select_append, select_group, where, and server.

The advantage of using these DatasetModule methods to define your dataset methods is that they can take advantage of dataset caching to improve performance.

Any public methods in the dataset module will have class methods created that call the method on the dataset, assuming that the class method is not already defined.

db ()

Source

    # File lib/sequel/model/base.rb
354 def db
355   return @db if @db
356   @db = self == Model ? Sequel.synchronize{DATABASES.first} : superclass.db
357   raise(Error, "No database associated with #{self}: have you called Sequel.connect or #{self}.db= ?") unless @db
358   @db
359 end

Returns the database associated with the Model class. If this model doesn’t have a database associated with it, assumes the superclass’s database, or the first object in Sequel::DATABASES. If no Sequel::Database object has been created, raises an error.

Artist.db.transaction do # BEGIN
  Artist.create(name: 'Bob')
  # INSERT INTO artists (name) VALUES ('Bob')
end # COMMIT

db= (db)

Source

    # File lib/sequel/model/base.rb
375 def db=(db)
376   raise Error, "Cannot use Sequel::Model.db= on model with existing dataset.  Use Sequel::Model.dataset= instead." if @dataset
377   @db = db
378 end

Sets the database associated with the Model class. Should only be used if the Model class currently does not have a dataset defined.

This can be used directly on Sequel::Model to set the default database to be used by subclasses, or to override the database used for specific models:

Sequel::Model.db = DB1
Artist = Class.new(Sequel::Model)
Artist.db = DB2

Note that you should not use this to change the model’s database at runtime. If you have that need, you should look into Sequel’s sharding support, or consider using separate model classes per Database.

db_schema ()

Source

    # File lib/sequel/model/base.rb
388 def db_schema
389   return @db_schema if @db_schema
390   return nil if frozen?
391   @db_schema = get_db_schema
392 end

Returns the cached schema information if available or gets it from the database. This is a hash where keys are column symbols and values are hashes of information related to the column. See Database#schema.

Artist.db_schema
# {:id=>{:type=>:integer, :primary_key=>true, ...},
#  :name=>{:type=>:string, :primary_key=>false, ...}}

def_Model (mod)

Source

    # File lib/sequel/model/base.rb
143 def def_Model(mod)
144   model = self
145   mod.define_singleton_method(:Model) do |source|
146     model.Model(source)
147   end
148 end

Define a Model method on the given module that calls the Model method on the receiver. This is how the Sequel::Model() method is defined, and allows you to define Model() methods on other modules, making it easier to have custom model settings for all models under a namespace. Example:

module Foo
  Model = Class.new(Sequel::Model)
  Model.def_Model(self)
  DB = Model.db = Sequel.connect(ENV['FOO_DATABASE_URL'])
  Model.plugin :prepared_statements

  class Bar < Model
    # Uses Foo::DB[:bars]
  end

  class Baz < Model(:my_baz)
    # Uses Foo::DB[:my_baz]
  end
end

def_column_alias (meth, column)

Source

    # File lib/sequel/model/base.rb
396 def def_column_alias(meth, column)
397   clear_setter_methods_cache
398   overridable_methods_module.module_eval do
399     define_method(meth){self[column]}
400     define_method("#{meth}="){|v| self[column] = v}
401   end
402 end

Create a column alias, where the column methods have one name, but the underlying storage uses a different name.

find (*args, &block)

Source

    # File lib/sequel/model/base.rb
412 def find(*args, &block)
413   first(*args, &block)
414 end

Finds a single record according to the supplied filter. You are encouraged to use Model[] or Model.first instead of this method.

Artist.find(name: 'Bob')
# SELECT * FROM artists WHERE (name = 'Bob') LIMIT 1

Artist.find{name > 'M'}
# SELECT * FROM artists WHERE (name > 'M') LIMIT 1

find_or_create (cond, &block)

Source

    # File lib/sequel/model/base.rb
428 def find_or_create(cond, &block)
429   find(cond) || create(cond, &block)
430 end

Like find but invokes create with given conditions when record does not exist. Unlike find in that the block used in this method is not passed to find, but instead is passed to create only if find does not return an object.

Artist.find_or_create(name: 'Bob')
# SELECT * FROM artists WHERE (name = 'Bob') LIMIT 1
# INSERT INTO artists (name) VALUES ('Bob')

Artist.find_or_create(name: 'Jim'){|a| a.hometown = 'Sactown'}
# SELECT * FROM artists WHERE (name = 'Jim') LIMIT 1
# INSERT INTO artists (name, hometown) VALUES ('Jim', 'Sactown')

freeze ()

Source

    # File lib/sequel/model/base.rb
433 def freeze
434   return self if frozen?
435   dataset_module.freeze
436   overridable_methods_module.freeze
437 
438   if @dataset
439     db_schema.freeze.each_value(&:freeze)
440     columns.freeze
441     setter_methods.freeze
442   else
443     @setter_methods = [].freeze
444   end
445 
446   @dataset_method_modules.freeze
447   @default_set_fields_options.freeze
448   @plugins.freeze
449 
450   super
451 end

Freeze a model class, disallowing any further changes to it.

Calls superclass method

has_dataset? ()

Source

    # File lib/sequel/model/base.rb
456 def has_dataset?
457   !@dataset.nil?
458 end

Whether the model has a dataset. True for most model classes, but can be false if the model class is an abstract model class designed for subclassing, such as Sequel::Model itself.

implicit_table_name ()

Source

    # File lib/sequel/model/base.rb
472 def implicit_table_name
473   pluralize(underscore(demodulize(name))).to_sym
474 end

Returns the implicit table name for the model class, which is the demodulized, underscored, pluralized name of the class.

Artist.implicit_table_name # => :artists
Foo::ArtistAlias.implicit_table_name # => :artist_aliases

include (*mods)

Source

    # File lib/sequel/model/base.rb
462 def include(*mods)
463   clear_setter_methods_cache
464   super
465 end

Clear the setter_methods cache when a module is included, as it may contain setter methods.

Calls superclass method

load (values)

Source

    # File lib/sequel/model/base.rb
477 def load(values)
478   call(values)
479 end

Calls call with the values hash.

no_primary_key ()

Source

    # File lib/sequel/model/base.rb
487 def no_primary_key
488   clear_setter_methods_cache
489   self.simple_pk = @primary_key = nil
490 end

Mark the model as not having a primary key. Not having a primary key can cause issues, among which is that you won’t be able to update records.

Artist.primary_key # => :id
Artist.no_primary_key
Artist.primary_key # => nil

plugin (plugin, *args, &block)

Source

    # File lib/sequel/model/base.rb
496 def plugin(plugin, *args, &block)
497   m = plugin.is_a?(Module) ? plugin : plugin_module(plugin)
498 
499   if !m.respond_to?(:apply) && !m.respond_to?(:configure) && (!args.empty? || block)
500     Deprecation.deprecate("Plugin #{plugin} accepts no arguments or block, and passing arguments/block to it", "Remove arguments and block when loading the plugin")
501   end
502 
503   unless @plugins.include?(m)
504     @plugins << m
505     m.apply(self, *args, &block) if m.respond_to?(:apply)
506     if m.const_defined?(:ClassMethods, false)
507       class_methods = m::ClassMethods
508       extend(class_methods)
509       if class_methods.private_method_defined?(:each_model_instance_variable)
510         def_initialize_nil_instance_variables
511       end
512     end
513     include(m::InstanceMethods) if m.const_defined?(:InstanceMethods, false)
514     if m.const_defined?(:DatasetMethods, false)
515       dataset_extend(m::DatasetMethods, :create_class_methods=>false)
516     end
517   end
518 
519   m.configure(self, *args, &block) if m.respond_to?(:configure)
520 end

Loads a plugin for use with the model class, passing optional arguments to the plugin. If the plugin is a module, load it directly. Otherwise, require the plugin from sequel/plugins/#{plugin} and then attempt to load the module using a the camelized plugin name under Sequel::Plugins.

primary_key_hash (value)

Source

    # File lib/sequel/model/base.rb
533 def primary_key_hash(value)
534   case key = @primary_key
535   when Symbol
536     {key => value}
537   when Array
538     hash = {}
539     key.zip(Array(value)){|k,v| hash[k] = v}
540     hash
541   else
542     raise(Error, "#{self} does not have a primary key")
543   end
544 end

Returns primary key attribute hash. If using a composite primary key value such be an array with values for each primary key in the correct order. For a standard primary key, value should be an object with a compatible type for the key. If the model does not have a primary key, raises an Error.

Artist.primary_key_hash(1) # => {:id=>1}
Artist.primary_key_hash([1, 2]) # => {:id1=>1, :id2=>2}

qualified_primary_key (qualifier=table_name)

Source

    # File lib/sequel/model/base.rb
553 def qualified_primary_key(qualifier=table_name)
554   case key = @primary_key
555   when Symbol
556     SQL::QualifiedIdentifier.new(qualifier, key)
557   when Array
558     key.map{|k| SQL::QualifiedIdentifier.new(qualifier, k)}
559   else
560     raise(Error, "#{self} does not have a primary key")
561   end
562 end

Return a qualified identifier or array of qualified identifiers for the model’s primary key. Uses the given qualifier if provided, or the table_name otherwise. If the model does not have a primary key, raises an Error.

Artist.order(Artist.qualified_primary_key)
# SELECT * FROM artists ORDER BY artists.id

qualified_primary_key_hash (value, qualifier=table_name)

Source

    # File lib/sequel/model/base.rb
571 def qualified_primary_key_hash(value, qualifier=table_name)
572   case key = @primary_key
573   when Symbol
574     {SQL::QualifiedIdentifier.new(qualifier, key) => value}
575   when Array
576     hash = {}
577     key.zip(Array(value)){|k,v| hash[SQL::QualifiedIdentifier.new(qualifier, k)] = v}
578     hash
579   else
580     raise(Error, "#{self} does not have a primary key")
581   end
582 end

Return a hash where the keys are qualified column references. Uses the given qualifier if provided, or the table_name otherwise. This is useful if you plan to join other tables to this table and you want the column references to be qualified. If the model does not have a primary key, raises an Error.

Artist.where(Artist.qualified_primary_key_hash(1))
# SELECT * FROM artists WHERE (artists.id = 1)

restrict_primary_key ()

Source

    # File lib/sequel/model/base.rb
587 def restrict_primary_key
588   clear_setter_methods_cache
589   @restrict_primary_key = true
590 end

Restrict the setting of the primary key(s) when using mass assignment (e.g. set). Because this is the default, this only make sense to use in a subclass where the parent class has used unrestrict_primary_key.

restrict_primary_key? ()

Source

    # File lib/sequel/model/base.rb
594 def restrict_primary_key?
595   @restrict_primary_key
596 end

Whether or not setting the primary key(s) when using mass assignment (e.g. set) is restricted, true by default.

set_dataset (ds, opts=OPTS)

Source

    # File lib/sequel/model/base.rb
624 def set_dataset(ds, opts=OPTS)
625   inherited = opts[:inherited]
626   @dataset = convert_input_dataset(ds)
627   @require_modification = @dataset.provides_accurate_rows_matched? if require_modification.nil?
628   if inherited
629     self.simple_table = superclass.simple_table
630     @columns = superclass.instance_variable_get(:@columns)
631     @db_schema = superclass.instance_variable_get(:@db_schema)
632   else
633     @dataset = @dataset.with_extend(*@dataset_method_modules.reverse)
634     @db_schema = get_db_schema
635   end
636 
637   @fast_pk_lookup_sql = @fast_instance_delete_sql = nil unless @dataset.supports_placeholder_literalizer?
638   reset_instance_dataset
639   self
640 end

Sets the dataset associated with the Model class. ds can be a Symbol, LiteralString, SQL::Identifier, SQL::QualifiedIdentifier, SQL::AliasedExpression (all specifying a table name in the current database), or a Dataset. If a dataset is used, the model’s database is changed to the database of the given dataset. If a dataset is not used, a dataset is created from the current database with the table name given. Other arguments raise an Error. Returns self.

It also attempts to determine the database schema for the model, based on the given dataset.

Note that you should not use this to change the model’s dataset at runtime. If you have that need, you should look into Sequel’s sharding support, or creating a separate Model class per dataset

You should avoid calling this method directly if possible. Instead you should set the table name or dataset when creating the model class:

# table name
class Artist < Sequel::Model(:tbl_artists)
end

# dataset
class Artist < Sequel::Model(DB[:tbl_artists])
end

set_model_instance_variables (*ivs)

Source

    # File lib/sequel/model/base.rb
644 def set_model_instance_variables(*ivs)
645   Plugins.model_instance_variables(singleton_class, *ivs)
646   def_initialize_nil_instance_variables
647 end

Set instance variables used by instances of this model class. Only has an effect if shape_friendly is true.

set_primary_key (key)

Source

    # File lib/sequel/model/base.rb
663 def set_primary_key(key)
664   clear_setter_methods_cache
665   if key.is_a?(Array)
666     if key.length < 2
667       key = key.first
668     else
669       key = key.dup.freeze
670     end
671   end
672   self.simple_pk = if key && !key.is_a?(Array)
673     (@dataset || db).literal(key).freeze
674   end
675   @primary_key = key
676 end

Sets the primary key for this model. You can use either a regular or a composite primary key. To not use a primary key, set to nil or use no_primary_key. On most adapters, Sequel can automatically determine the primary key to use, so this method is not needed often.

class Person < Sequel::Model
  # regular key
  set_primary_key :person_id
end

class Tagging < Sequel::Model
  # composite key
  set_primary_key [:taggable_id, :tag_id]
end

setter_methods ()

Source

    # File lib/sequel/model/base.rb
679 def setter_methods
680   @setter_methods || (@setter_methods = get_setter_methods)
681 end

Cache of setter methods to allow by default, in order to speed up mass assignment.

shape_friendly= (v)

Source

    # File lib/sequel/model/base.rb
684 def shape_friendly=(v)
685   @shape_friendly = v
686   def_initialize_nil_instance_variables
687 end

Set whether the model should be shape friendly.

table_name ()

Source

    # File lib/sequel/model/base.rb
695 def table_name
696   dataset.first_source_alias
697 end

Returns name of primary table for the dataset. If the table for the dataset is aliased, returns the aliased name.

Artist.table_name # => :artists
Sequel::Model(:foo).table_name # => :foo
Sequel::Model(Sequel[:foo].as(:bar)).table_name # => :bar

unrestrict_primary_key ()

Source

    # File lib/sequel/model/base.rb
705 def unrestrict_primary_key
706   clear_setter_methods_cache
707   @restrict_primary_key = false
708 end

Allow the setting of the primary key(s) when using the mass assignment methods. Using this method can open up security issues, be very careful before using it.

Artist.set(id: 1) # Error
Artist.unrestrict_primary_key
Artist.set(id: 1) # No Error

with_pk (pk)

Source

    # File lib/sequel/model/base.rb
711 def with_pk(pk)
712   primary_key_lookup(pk)
713 end

Return the model instance with the primary key, or nil if there is no matching record.

with_pk! (pk)

Source

    # File lib/sequel/model/base.rb
716 def with_pk!(pk)
717   with_pk(pk) || raise(NoMatchingRow.new(dataset))
718 end

Return the model instance with the primary key, or raise NoMatchingRow if there is no matching record.

Private Instance Methods

check_non_connection_error (do_raise=require_valid_table) { || ... }

Source

    # File lib/sequel/model/base.rb
727 def check_non_connection_error(do_raise=require_valid_table)
728   db.transaction(:savepoint=>:only){yield}
729 rescue Sequel::DatabaseConnectionError, Sequel::DatabaseDisconnectError
730   raise
731 rescue Sequel::Error
732   raise if do_raise
733 end

Yield to the passed block and if do_raise is false, swallow Sequel::Errors other than DatabaseConnectionError and DatabaseDisconnectError.

convert_input_dataset (ds)

Source

    # File lib/sequel/model/base.rb
737 def convert_input_dataset(ds)
738   case ds
739   when Symbol, SQL::Identifier, SQL::QualifiedIdentifier
740     self.simple_table = db.literal(ds).freeze
741     ds = db.from(ds)
742   when SQL::AliasedExpression, LiteralString
743     self.simple_table = nil
744     ds = db.from(ds)
745   when Dataset
746     ds = ds.from_self(:alias=>ds.first_source) if ds.joined_dataset?
747 
748     self.simple_table = if ds.send(:simple_select_all?)
749       ds.literal(ds.first_source_table).freeze
750     end
751     @db = ds.db
752   else
753     raise(Error, "Model.set_dataset takes one of the following classes as an argument: Symbol, LiteralString, SQL::Identifier, SQL::QualifiedIdentifier, SQL::AliasedExpression, Dataset")
754   end
755 
756   set_dataset_row_proc(ds.clone(:model=>self))
757 end

Convert the given object to a Dataset that should be used as this model’s dataset.

dataset_extend (mod, opts=OPTS)

Source

    # File lib/sequel/model/base.rb
762 def dataset_extend(mod, opts=OPTS)
763   @dataset = @dataset.with_extend(mod) if @dataset
764   reset_instance_dataset
765   dataset_method_modules << mod
766   unless opts[:create_class_methods] == false
767     mod.public_instance_methods.each{|meth| def_model_dataset_method(meth)}
768   end
769 end

Add the module to the class’s dataset_method_modules. Extend the dataset with the module if the model has a dataset. Add dataset methods to the class for all public dataset methods.

dataset_methods_module ()

Source

    # File lib/sequel/model/base.rb
810 def dataset_methods_module
811   return @dataset_methods_module if defined?(@dataset_methods_module)
812   mod_name = "#{name}::@dataset_methods_module"
813   Sequel.synchronize{@dataset_methods_module ||= Sequel.set_temp_name(Module.new){mod_name}}
814   extend(@dataset_methods_module)
815   @dataset_methods_module
816 end

Module that the class methods that call dataset methods are kept in. This allows the methods to be overridden and call super with the default behavior.

def_bad_column_accessor (column)

Source

    # File lib/sequel/model/base.rb
772 def def_bad_column_accessor(column)
773   im = instance_methods
774   overridable_methods_module.module_eval do
775     meth = :"#{column}="
776     unless im.include?(column)
777       define_method(column){self[column]}
778       alias_method(column, column)
779     end
780     unless im.include?(meth)
781       define_method(meth){|v| self[column] = v}
782       alias_method(meth, meth)
783     end
784   end
785 end

Create a column accessor for a column with a method name that is hard to use in ruby code.

def_column_accessor (*columns)

Source

    # File lib/sequel/model/base.rb
789 def def_column_accessor(*columns)
790   clear_setter_methods_cache
791   columns, bad_columns = columns.partition{|x| /\A[A-Za-z_][A-Za-z0-9_]*\z/.match(x.to_s)}
792   bad_columns.each{|x| def_bad_column_accessor(x)}
793   im = instance_methods
794   columns.each do |column|
795     meth = :"#{column}="
796     unless im.include?(column)
797       overridable_methods_module.module_eval("def #{column}; self[:#{column}] end", __FILE__, __LINE__)
798       overridable_methods_module.send(:alias_method, column, column)
799     end
800     unless im.include?(meth)
801       overridable_methods_module.module_eval("def #{meth}(v); self[:#{column}] = v end", __FILE__, __LINE__)
802       overridable_methods_module.send(:alias_method, meth, meth)
803     end
804   end
805 end

Create the column accessors. For columns that can be used as method names directly in ruby code, use a string to define the method for speed. For other columns names, use a block.

def_initialize_nil_instance_variables ()

Source

    # File lib/sequel/model/base.rb
842       def def_initialize_nil_instance_variables
843         if @shape_friendly
844           ivs = []
845           each_model_instance_variable do |iv|
846             unless iv.match(/\A@[a-z_][a-z0-9_]*\z/)
847               raise Error, "invalid model instance variable used"
848             end
849 
850             ivs << iv
851           end
852           ivs.uniq!
853           ivs = ivs.reverse.join(" = ")
854           new_method_content = "#{ivs} = nil"
855           new_from_db_method_content = "#{ivs} = @new = @modified = nil"
856         end
857 
858         class_eval(<<-RUBY, __FILE__, __LINE__+1)
859           def _initialize_nil_instance_variables
860             #{new_method_content}
861           end
862           def _initialize_from_db_nil_instance_variables
863             #{new_from_db_method_content}
864           end
865         RUBY
866         private :_initialize_nil_instance_variables, :_initialize_from_db_nil_instance_variables
867         alias_method :_initialize_nil_instance_variables, :_initialize_nil_instance_variables
868         alias_method :_initialize_from_db_nil_instance_variables, :_initialize_from_db_nil_instance_variables
869         nil
870       end

Defines the private _initialize_nil_instance_variables method. If shape_friendly is true, defines a method that initials the model’s instance variables to nil. If shape_friendly is not true, does nothing.

def_model_dataset_method (meth)

Source

    # File lib/sequel/model/base.rb
819       def def_model_dataset_method(meth)
820         return if respond_to?(meth, true)
821 
822         mod = dataset_methods_module
823 
824         if meth.to_s =~ /\A[A-Za-z_][A-Za-z0-9_]*\z/
825           mod.module_eval(<<END, __FILE__, __LINE__ + 1)
826 def #{meth}(*args, &block); dataset.#{meth}(*args, &block) end
827 ruby2_keywords :#{meth} if respond_to?(:ruby2_keywords, true)
828 END
829         else
830           mod.send(:define_method, meth){|*args, &block| dataset.public_send(meth, *args, &block)}
831           # :nocov:
832           mod.send(:ruby2_keywords, meth) if respond_to?(:ruby2_keywords, true)
833           # :nocov:
834         end
835         mod.send(:alias_method, meth, meth)
836       end

Define a model method that calls the dataset method with the same name.

each_model_instance_variable () { |iv| ... }

Source

    # File lib/sequel/model/base.rb
874 def each_model_instance_variable
875   [
876     :@changed_columns,
877     :@errors,
878     :@raise_on_save_failure,
879     :@raise_on_typecast_failure,
880     :@require_modification,
881     :@server,
882     :@singleton_setter_added,
883     :@skip_validation_on_next_save,
884     :@strict_param_setting,
885     :@this,
886     :@typecast_empty_string_to_nil,
887     :@typecast_on_assignment,
888     :@use_transactions,
889   ].each{|iv| yield iv}
890 end

Yield the default model instance variables. Designed only for use by def_initialize_nil_instance_variables.

get_db_schema (reload = reload_db_schema?)

Source

    # File lib/sequel/model/base.rb
895 def get_db_schema(reload = reload_db_schema?)
896   set_columns(nil)
897   return nil unless @dataset
898   schema_hash = {}
899   ds_opts = dataset.opts
900   get_columns = proc{check_non_connection_error{columns} || []}
901   schema_array = get_db_schema_array(reload) if db.supports_schema_parsing?
902   if schema_array
903     schema_array.each{|k,v| schema_hash[k] = v}
904 
905     # Set the primary key(s) based on the schema information,
906     # if the schema information includes primary key information
907     if schema_array.all?{|k,v| v.has_key?(:primary_key)}
908       pks = schema_array.map{|k,v| k if v[:primary_key]}.compact
909       pks.length > 0 ? set_primary_key(pks) : no_primary_key
910     end
911 
912     if (select = ds_opts[:select]) && !(select.length == 1 && select.first.is_a?(SQL::ColumnAll))
913       # We don't remove the columns from the schema_hash,
914       # as it's possible they will be used for typecasting
915       # even if they are not selected.
916       cols = get_columns.call
917       cols.each{|c| schema_hash[c] ||= {}}
918       def_column_accessor(*schema_hash.keys)
919     else
920       # Dataset is for a single table with all columns,
921       # so set the columns based on the order they were
922       # returned by the schema.
923       cols = schema_array.map{|k,v| k}
924       set_columns(cols)
925       # Also set the columns for the dataset, so the dataset
926       # doesn't have to do a query to get them.
927       dataset.send(:columns=, cols)
928     end
929   else
930     # If the dataset uses multiple tables or custom sql or getting
931     # the schema raised an error, just get the columns and
932     # create an empty schema hash for it.
933     get_columns.call.each{|c| schema_hash[c] = {}}
934   end
935   schema_hash
936 end

Get the schema from the database, fall back on checking the columns via the database if that will return inaccurate results or if it raises an error.

get_db_schema_array (reload)

Source

    # File lib/sequel/model/base.rb
940 def get_db_schema_array(reload)
941   check_non_connection_error(false){db.schema(dataset, :reload=>reload)}
942 end

Get the array of schema information for the dataset. Returns nil if the schema information cannot be determined.

get_setter_methods ()

Source

    # File lib/sequel/model/base.rb
946 def get_setter_methods
947   meths = instance_methods.map(&:to_s).select{|l| l.end_with?('=')} - RESTRICTED_SETTER_METHODS
948   meths -= Array(primary_key).map{|x| "#{x}="} if primary_key && restrict_primary_key?
949   meths
950 end

Uncached version of setter_methods, to be overridden by plugins that want to modify the methods used.

inherited (subclass)

Source

    # File lib/sequel/model/base.rb
961 def inherited(subclass)
962   super
963   ivs = subclass.instance_variables
964   inherited_instance_variables.each do |iv, dup|
965     if (sup_class_value = instance_variable_get(iv)) && dup
966       sup_class_value = case dup
967       when :dup
968         sup_class_value.dup
969       when :hash_dup
970         h = {}
971         sup_class_value.each{|k,v| h[k] = v.dup}
972         h
973       when Proc
974         dup.call(sup_class_value)
975       else
976         raise Error, "bad inherited instance variable type: #{dup.inspect}"
977       end
978     end
979     subclass.instance_variable_set(iv, sup_class_value)
980   end
981 
982   unless ivs.include?(:@dataset)
983     if @dataset && self != Model
984       subclass.set_dataset(@dataset.clone, :inherited=>true)
985     elsif (n = subclass.name) && !n.to_s.empty?
986       db
987       subclass.set_dataset(subclass.implicit_table_name)
988     end
989   end
990 end

If possible, set the dataset for the model subclass as soon as it is created. Also, make sure the inherited class instance variables are copied into the subclass.

Sequel queries the database to get schema information as soon as a model class is created:

class Artist < Sequel::Model # Causes schema query
end

Calls superclass method

inherited_instance_variables ()

Source

     # File lib/sequel/model/base.rb
 998 def inherited_instance_variables
 999   {
1000     :@cache_anonymous_models=>nil,
1001     :@dataset_method_modules=>:dup,
1002     :@dataset_module_class=>nil,
1003     :@db=>nil,
1004     :@default_set_fields_options=>:dup,
1005     :@fast_instance_delete_sql=>nil,
1006     :@fast_pk_lookup_sql=>nil,
1007     :@plugins=>:dup,
1008     :@primary_key=>nil,
1009     :@raise_on_save_failure=>nil,
1010     :@raise_on_typecast_failure=>nil,
1011     :@require_modification=>nil,
1012     :@require_valid_table=>nil,
1013     :@restrict_primary_key=>nil,
1014     :@setter_methods=>nil,
1015     :@shape_friendly=>nil,
1016     :@simple_pk=>nil,
1017     :@simple_table=>nil,
1018     :@strict_param_setting=>nil,
1019     :@typecast_empty_string_to_nil=>nil,
1020     :@typecast_on_assignment=>nil,
1021     :@use_transactions=>nil
1022   }
1023 end

A hash of instance variables to automatically set up in subclasses. Keys are instance variable symbols, values should be:

nil: Assign directly from superclass to subclass (frozen objects)
:dup: Dup object when assigning from superclass to subclass (mutable objects)
:hash_dup: Assign hash with same keys, but dup all the values
Proc: Call with subclass to do the assignment

late_binding_class_option (opts, default)

Source

     # File lib/sequel/model/base.rb
1029 def late_binding_class_option(opts, default)
1030   case opts[:class]
1031     when String, Symbol
1032       # Delete :class to allow late binding
1033       class_name = opts.delete(:class).to_s
1034 
1035       if (namespace = opts[:class_namespace]) && !class_name.start_with?('::')
1036         class_name = "::#{namespace}::#{class_name}"
1037       end
1038 
1039       opts[:class_name] ||= class_name
1040     when Class
1041       opts[:class_name] ||= opts[:class].name
1042   end
1043 
1044   opts[:class_name] ||= '::' + ((name || '').split("::")[0..-2] + [camelize(default)]).join('::')
1045 end

For the given opts hash and default name or :class option, add a :class_name option unless already present which contains the name of the class to use as a string. The purpose is to allow late binding to the class later using constantize.

method_added (meth)

Source

     # File lib/sequel/model/base.rb
1048 def method_added(meth)
1049   clear_setter_methods_cache if meth.to_s.end_with?('=')
1050   super
1051 end

Clear the setter_methods cache when a setter method is added.

Calls superclass method

overridable_methods_module ()

Source

     # File lib/sequel/model/base.rb
1055 def overridable_methods_module
1056   return @overridable_methods_module if defined?(@overridable_methods_module)
1057   mod_name = "#{name}::@overridable_methods_module"
1058   Sequel.synchronize{@overridable_methods_module ||= Sequel.set_temp_name(Module.new){mod_name}}
1059   include(@overridable_methods_module)
1060   @overridable_methods_module
1061 end

Module that the class includes that holds methods the class adds for column accessors and associations so that the methods can be overridden with super.

plugin_module (plugin)

Source

     # File lib/sequel/model/base.rb
1065 def plugin_module(plugin)
1066   module_name = plugin.to_s.gsub(/(^|_)(.)/){|x| x[-1..-1].upcase}
1067   unless Sequel::Plugins.const_defined?(module_name, false)
1068     require "sequel/plugins/#{plugin}"
1069   end
1070   Sequel::Plugins.const_get(module_name)
1071 end

Returns the module for the specified plugin. If the module is not defined, the corresponding plugin required.

primary_key_lookup (pk)

Source

     # File lib/sequel/model/base.rb
1079 def primary_key_lookup(pk)
1080   if sql = @fast_pk_lookup_sql
1081     sql = sql.dup
1082     ds = dataset
1083     ds.literal_append(sql, pk)
1084     ds.fetch_rows(sql){|r| return ds.row_proc.call(r)}
1085     nil
1086   else
1087     dataset.first(primary_key_hash(pk))
1088   end
1089 end

Find the row in the dataset that matches the primary key. Uses a static SQL optimization if the table and primary key are simple.

This method should not be called with a nil primary key, in case it is overridden by plugins which assume that the passed argument is valid.

reload_db_schema? ()

Source

     # File lib/sequel/model/base.rb
1092 def reload_db_schema?
1093   false
1094 end

Whether to reload the database schema by default, ignoring any cached value.

reset_fast_pk_lookup_sql ()

Source

     # File lib/sequel/model/base.rb
1098 def reset_fast_pk_lookup_sql
1099   @fast_pk_lookup_sql = if @simple_table && @simple_pk
1100     "SELECT * FROM #{@simple_table} WHERE #{@simple_pk} = ".freeze
1101   end
1102   @fast_instance_delete_sql = if @simple_table && @simple_pk
1103     "DELETE FROM #{@simple_table} WHERE #{@simple_pk} = ".freeze
1104   end
1105 end

Reset the cached fast primary lookup SQL if a simple table and primary key are used, or set it to nil if not used.

reset_instance_dataset ()

Source

     # File lib/sequel/model/base.rb
1109 def reset_instance_dataset
1110   @instance_dataset = @dataset.limit(1).naked.skip_limit_check if @dataset
1111 end

Reset the instance dataset to a modified copy of the current dataset, should be used whenever the model’s dataset is modified.

set_columns (new_columns)

Source

     # File lib/sequel/model/base.rb
1114 def set_columns(new_columns)
1115   @columns = new_columns
1116   def_column_accessor(*new_columns) if new_columns
1117   @columns
1118 end

Set the columns for this model and create accessor methods for each column.

set_dataset_row_proc (ds)

Source

     # File lib/sequel/model/base.rb
1121 def set_dataset_row_proc(ds)
1122   ds.with_row_proc(self)
1123 end

Set the dataset’s row_proc to the current model.

simple_pk= (pk)

Source

     # File lib/sequel/model/base.rb
1126 def simple_pk=(pk)
1127   @simple_pk = pk
1128   reset_fast_pk_lookup_sql
1129 end

Reset the fast primary key lookup SQL when the simple_pk value changes.

simple_table= (t)

Source

     # File lib/sequel/model/base.rb
1132 def simple_table=(t)
1133   @simple_table = t
1134   reset_fast_pk_lookup_sql
1135 end

Reset the fast primary key lookup SQL when the simple_table value changes.