module Sequel::Model::InstanceMethods

  1. lib/sequel/model/base.rb

Sequel::Model instance methods that implement basic model functionality.

  • All of the model before/after/around hooks are implemented as instance methods that are called by Sequel when the appropriate action occurs. For example, when destroying a model object, Sequel will call around_destroy, which will call before_destroy, do the destroy, and then call after_destroy.

  • The following instance_methods all call the class method of the same name: columns, db, primary_key, db_schema.

  • The following accessor methods are defined via metaprogramming: raise_on_save_failure, raise_on_typecast_failure, require_modification, strict_param_setting, typecast_empty_string_to_nil, typecast_on_assignment, and use_transactions. The setter methods will change the setting for the instance, and the getter methods will check for an instance setting, then try the class setting if no instance setting has been set.

Public Instance Aliases

pk_equal? -> ===

If the receiver has a primary key value, returns true if the objects have the same class and primary key value. If the receiver's primary key value is nil or is an array containing nil, returns false.

Artist[1].pk_equal?(Artist[1]) # => true # => false
Artist[1].set(:name=>'Bob').pk_equal?(Artist[1]) # => true


to_hash [R]

The hash of attribute values. Keys are symbols with the names of the underlying database columns. The returned hash is a reference to the receiver's values hash, and modifying it will also modify the receiver's values. 'Bob').values # => {:name=>'Bob'}
Artist[1].values # => {:id=>1, :name=>'Jim', ...}
values [R]

The hash of attribute values. Keys are symbols with the names of the underlying database columns. The returned hash is a reference to the receiver's values hash, and modifying it will also modify the receiver's values. 'Bob').values # => {:name=>'Bob'}
Artist[1].values # => {:id=>1, :name=>'Jim', ...}

Public Class methods

new(values = OPTS)

Creates new instance and passes the given values to set. If a block is given, yield the instance to the block.



should be a hash to pass to set. 'Bob') do |a| = 'Bob'
[show source]
     # File lib/sequel/model/base.rb
1090 def initialize(values = OPTS)
1091   @values = {}
1092   @new = true
1093   @modified = true
1094   initialize_set(values)
1095   _clear_changed_columns(:initialize)
1096   yield self if block_given?
1097 end

Public Instance methods


Alias of eql?

[show source]
     # File lib/sequel/model/base.rb
1127 def ==(obj)
1128   eql?(obj)
1129 end

Case equality. By default, checks equality of the primary key value, see pk_equal?.

Artist[1] === Artist[1] # => true === # => false
Artist[1].set(:name=>'Bob') === Artist[1] # => true
[show source]
     # File lib/sequel/model/base.rb
1137 def ===(obj)
1138   case pkv = pk
1139   when nil
1140     return false
1141   when Array
1142     return false if pkv.any?(&:nil?)
1143   end
1145   (obj.class == model) && ( == pkv)
1146 end

Returns value of the column's attribute.

Artist[1][:id] #=> 1
[show source]
     # File lib/sequel/model/base.rb
1102 def [](column)
1103   @values[column]
1104 end
[]=(column, value)

Sets the value for the given column. If typecasting is enabled for this object, typecast the value based on the column's type. If this is a new record or the typecasted value isn't the same as the current value for the column, mark the column as changed.

a =
a[:name] = 'Bob'
a.values #=> {:name=>'Bob'}
[show source]
     # File lib/sequel/model/base.rb
1114 def []=(column, value)
1115   # If it is new, it doesn't have a value yet, so we should
1116   # definitely set the new value.
1117   # If the column isn't in @values, we can't assume it is
1118   # NULL in the database, so assume it has changed.
1119   v = typecast_value(column, value)
1120   vals = @values
1121   if new? || !vals.include?(column) || v != (c = vals[column]) || v.class != c.class
1122     change_column_value(column, v)
1123   end
1124 end

The autoincrementing primary key for this model object. Should be overridden if you have a composite primary key with one part of it being autoincrementing.

[show source]
     # File lib/sequel/model/base.rb
1169 def autoincrementing_primary_key
1170   primary_key
1171 end

Cancel the current action. Should be called in before hooks to halt the processing of the action. If a msg argument is given and the model instance is configured to raise exceptions on failure, sets the message to use for the raised HookFailed exception.

[show source]
     # File lib/sequel/model/base.rb
1177 def cancel_action(msg=nil)
1178   raise_hook_failure(msg)
1179 end

The columns that have been updated. This isn't completely accurate, as it could contain columns whose values have not changed.

a = Artist[1]
a.changed_columns # => [] = 'Bob'
a.changed_columns # => [:name]
[show source]
     # File lib/sequel/model/base.rb
1188 def changed_columns
1189   _changed_columns
1190 end

Deletes and returns self. Does not run destroy hooks. Look into using destroy instead.

Artist[1].delete # DELETE FROM artists WHERE (id = 1)
# => #<Artist {:id=>1, ...}>
[show source]
     # File lib/sequel/model/base.rb
1197 def delete
1198   raise Sequel::Error, "can't delete frozen object" if frozen?
1199   _delete
1200   self
1201 end
destroy(opts = OPTS)

Like delete but runs hooks before and after delete. Uses a transaction if use_transactions is true or if the :transaction option is given and true.

Artist[1].destroy # BEGIN; DELETE FROM artists WHERE (id = 1); COMMIT;
# => #<Artist {:id=>1, ...}>
[show source]
     # File lib/sequel/model/base.rb
1209 def destroy(opts = OPTS)
1210   raise Sequel::Error, "can't destroy frozen object" if frozen?
1211   checked_save_failure(opts){checked_transaction(opts){_destroy(opts)}}
1212 end

Iterates through all of the current values using each.

Album[1].each{|k, v| puts "#{k} => #{v}"}
# id => 1
# name => 'Bob'
[show source]
     # File lib/sequel/model/base.rb
1219 def each(&block)
1220   @values.each(&block)
1221 end

Compares model instances by values.

Artist[1] == Artist[1] # => true == # => true
Artist[1].set(:name=>'Bob') == Artist[1] # => false
[show source]
     # File lib/sequel/model/base.rb
1228 def eql?(obj)
1229   (obj.class == model) && (obj.values == @values)
1230 end

Returns the validation errors associated with this object. See Errors.

[show source]
     # File lib/sequel/model/base.rb
1234 def errors
1235   @errors ||=
1236 end

Returns true when current instance exists, false otherwise. Generally an object that isn't new will exist unless it has been deleted. Uses a database query to check for existence, unless the model object is new, in which case this is always false.

Artist[1].exists? # SELECT 1 FROM artists WHERE (id = 1)
# => true
# => false
[show source]
     # File lib/sequel/model/base.rb
1248 def exists?
1249   new? ? false : !this.get(, :one)).nil?
1250 end

Ignore the model's setter method cache when this instances extends a module, as the module may contain setter methods.

[show source]
     # File lib/sequel/model/base.rb
1254 def extend(mod)
1255   @singleton_setter_added = true
1256   super
1257 end

Freeze the object in such a way that it is still usable but not modifiable. Once an object is frozen, you cannot modify it's values, changed_columns, errors, or dataset.

[show source]
     # File lib/sequel/model/base.rb
1262 def freeze
1263   unless errors.frozen?
1264     validate
1265     errors.freeze
1266   end
1267   values.freeze
1268   _changed_columns.freeze
1269   this if !new? && model.primary_key
1270   super
1271 end

Value that should be unique for objects with the same class and pk (if pk is not nil), or the same class and values (if pk is nil).

Artist[1].hash == Artist[1].hash # true
Artist[1].set(name: 'Bob').hash == Artist[1].hash # true == # true 'Bob').hash == # false
[show source]
     # File lib/sequel/model/base.rb
1280 def hash
1281   case primary_key
1282   when Array
1283     [model, !pk.all? ? @values : pk].hash
1284   when Symbol
1285     [model, pk.nil? ? @values : pk].hash
1286   else
1287     [model, @values].hash
1288   end
1289 end

Returns value for the :id attribute, even if the primary key is not id. To get the primary key value, use pk.

Artist[1].id # => 1
[show source]
     # File lib/sequel/model/base.rb
1295 def id
1296   @values[:id]
1297 end

Returns a string representation of the model instance including the class name and values.

[show source]
     # File lib/sequel/model/base.rb
1301 def inspect
1302   "#<#{} @values=#{inspect_values}>"
1303 end

Returns the keys in values. May not include all column names. # => [] 'Bob').keys # => [:name]
Artist[1].keys # => [:id, :name]
[show source]
     # File lib/sequel/model/base.rb
1310 def keys
1311   @values.keys
1312 end

Refresh this record using for_update (by default, or the specified style when given) unless this is a new record. Returns self. This can be used to make sure no other process is updating the record at the same time.

If style is a string, it will be used directly. You should never pass a string to this method that is derived from user input, as that can lead to SQL injection.

A symbol may be used for database independent locking behavior, but all supported symbols have separate methods (e.g. for_update).

a = Artist[1]
Artist.db.transaction do

a = Artist[2]
Artist.db.transaction do
  a.lock!('FOR NO KEY UPDATE')
[show source]
     # File lib/sequel/model/base.rb
1337 def lock!(style=:update)
1338   _refresh(this.lock_style(style)) unless new?
1339   self
1340 end

Remove elements of the model object that make marshalling fail. Returns self.

a = Artist[1]
[show source]
     # File lib/sequel/model/base.rb
1347 def marshallable!
1348   @this = nil
1349   self
1350 end

Explicitly mark the object as modified, so save_changes/update will run callbacks even if no columns have changed.

a = Artist[1]
a.save_changes # No callbacks run, as no changes
a.save_changes # Callbacks run, even though no changes made

If a column is given, specifically marked that column as modified, so that save_changes/update will include that column in the update. This should be used if you plan on mutating the column value instead of assigning a new column value:

a.modified!(:name)!(/[aeou]/, 'i')
[show source]
     # File lib/sequel/model/base.rb
1367 def modified!(column=nil)
1368   _add_changed_column(column) if column
1369   @modified = true
1370 end

Whether this object has been modified since last saved, used by save_changes to determine whether changes should be saved. New values are always considered modified.

a = Artist[1]
a.modified? # => false
a.set(name: 'Jim')
a.modified? # => true

If a column is given, specifically check if the given column has been modified:

a.modified?(:num_albums) # => false
a.num_albums = 10
a.modified?(:num_albums) # => true
[show source]
     # File lib/sequel/model/base.rb
1387 def modified?(column=nil)
1388   if column
1389     changed_columns.include?(column)
1390   else
1391     @modified || !changed_columns.empty?
1392   end
1393 end

Returns true if the current instance represents a new record. # => true
Artist[1].new? # => false
[show source]
     # File lib/sequel/model/base.rb
1399 def new?
1400   defined?(@new) ? @new : (@new = false)
1401 end

Returns the primary key value identifying the model instance. Raises an Error if this model does not have a primary key. If the model has a composite primary key, returns an array of values.

Artist[1].pk # => 1
Artist[[1, 2]].pk # => [1, 2]
[show source]
     # File lib/sequel/model/base.rb
1409 def pk
1410   raise(Error, "No primary key is associated with this model") unless key = primary_key
1411   if key.is_a?(Array)
1412     vals = @values
1413{|k| vals[k]}
1414   else
1415     @values[key]
1416   end
1417 end

Returns a hash mapping the receivers primary key column(s) to their values.

Artist[1].pk_hash # => {:id=>1}
Artist[[1, 2]].pk_hash # => {:id1=>1, :id2=>2}
[show source]
     # File lib/sequel/model/base.rb
1423 def pk_hash
1424   model.primary_key_hash(pk)
1425 end

Returns a hash mapping the receivers qualified primary key column(s) to their values.

# => {Sequel[:artists][:id]=>1}
Artist[[1, 2]].qualified_pk_hash
# => {Sequel[:artists][:id1]=>1, Sequel[:artists][:id2]=>2}
[show source]
     # File lib/sequel/model/base.rb
1433 def qualified_pk_hash(qualifier=model.table_name)
1434   model.qualified_primary_key_hash(pk, qualifier)
1435 end

Reloads attributes from database and returns self. Also clears all changed_columns information. Raises an Error if the record no longer exists in the database.

a = Artist[1] = 'Jim'
a.refresh # => 'Bob'
[show source]
     # File lib/sequel/model/base.rb
1445 def refresh
1446   raise Sequel::Error, "can't refresh frozen object" if frozen?
1447   _refresh(this)
1448   self
1449 end

Alias of refresh, but not aliased directly to make overriding in a plugin easier.

[show source]
     # File lib/sequel/model/base.rb
1452 def reload
1453   refresh
1454 end

Creates or updates the record, after making sure the record is valid and before hooks execute successfully. Fails if:

  • the record is not valid, or

  • before_save calls cancel_action, or

  • the record is new and before_create calls cancel_action, or

  • the record is not new and before_update calls cancel_action.

If save fails and either raise_on_save_failure or the :raise_on_failure option is true, it raises ValidationFailed or HookFailed. Otherwise it returns nil.

If it succeeds, it returns self.

Takes the following options:


save all changed columns, instead of all columns or the columns given


array of specific columns that should be saved.


set to true or false to override the current raise_on_save_failure setting


set the server/shard on the object before saving, and use that server/shard in any transaction.


set to true or false to override the current use_transactions setting


set to false to skip validation

[show source]
     # File lib/sequel/model/base.rb
1481 def save(opts=OPTS)
1482   raise Sequel::Error, "can't save frozen object" if frozen?
1483   set_server(opts[:server]) if opts[:server] 
1484   unless _save_valid?(opts)
1485     raise(validation_failed_error) if raise_on_failure?(opts)
1486     return
1487   end
1488   checked_save_failure(opts){checked_transaction(opts){_save(opts)}}
1489 end

Saves only changed columns if the object has been modified. If the object has not been modified, returns nil. If unable to save, returns false unless raise_on_save_failure is true.

a = Artist[1]
a.save_changes # => nil = 'Jim'
a.save_changes # UPDATE artists SET name = 'Bob' WHERE (id = 1)
# => #<Artist {:id=>1, :name=>'Jim', ...}
[show source]
     # File lib/sequel/model/base.rb
1500 def save_changes(opts=OPTS)
1501   save(Hash[opts].merge!(:changed=>true)) || false if modified? 
1502 end

Updates the instance with the supplied values with support for virtual attributes, raising an exception if a value is used that doesn't have a setter method (or ignoring it if strict_param_setting = false). Does not save the record.

artist.set(name: 'Jim') # => 'Jim'
[show source]
     # File lib/sequel/model/base.rb
1511 def set(hash)
1512   set_restricted(hash, :default)
1513 end
set_fields(hash, fields, opts=nil)

For each of the fields in the given array fields, call the setter method with the value of that hash entry for the field. Returns self.

You can provide an options hash, with the following options currently respected:


Can be set to :skip to skip missing entries or :raise to raise an Error for missing entries. The default behavior is not to check for missing entries, in which case the default value is used. To be friendly with most web frameworks, the missing check will also check for the string version of the argument in the hash if given a symbol.


artist.set_fields({name: 'Jim'}, [:name]) # => 'Jim'

artist.set_fields({hometown: 'LA'}, [:name]) # => nil
artist.hometown # => 'Sac' # => 'Jim'
artist.set_fields({}, [:name], missing: :skip) # => 'Jim' # => 'Jim'
artist.set_fields({}, [:name], missing: :raise)
# Sequel::Error raised
[show source]
     # File lib/sequel/model/base.rb
1541 def set_fields(hash, fields, opts=nil)
1542   opts = if opts
1543     model.default_set_fields_options.merge(opts)
1544   else
1545     model.default_set_fields_options
1546   end
1548   case missing = opts[:missing]
1549   when :skip, :raise
1550     do_raise = true if missing == :raise
1551     fields.each do |f|
1552       if hash.has_key?(f) 
1553         set_column_value("#{f}=", hash[f])
1554       elsif f.is_a?(Symbol) && hash.has_key?(sf = f.to_s)
1555         set_column_value("#{sf}=", hash[sf])
1556       elsif do_raise
1557         raise(Sequel::Error, "missing field in hash: #{f.inspect} not in #{hash.inspect}")
1558       end
1559     end
1560   else
1561     fields.each{|f| set_column_value("#{f}=", hash[f])}
1562   end
1563   self
1564 end

Set the shard that this object is tied to. Returns self.

[show source]
     # File lib/sequel/model/base.rb
1567 def set_server(s)
1568   @server = s
1569   @this = @this.server(s) if @this
1570   self
1571 end

Clear the setter_methods cache when a method is added

[show source]
     # File lib/sequel/model/base.rb
1574 def singleton_method_added(meth)
1575   @singleton_setter_added = true if meth.to_s.end_with?('=')
1576   super
1577 end

Skip all validation of the object on the next call to save, including the running of validation hooks. This is designed for and should only be used in cases where valid? is called before saving and the validate: false option cannot be passed to save.

[show source]
     # File lib/sequel/model/base.rb
1584 def skip_validation_on_next_save!
1585   @skip_validation_on_next_save = true
1586 end

Returns (naked) dataset that should return only this instance.

# SELECT * FROM artists WHERE (id = 1) LIMIT 1
[show source]
     # File lib/sequel/model/base.rb
1592 def this
1593   return @this if @this
1594   raise Error, "No dataset for model #{model}" unless ds = model.instance_dataset
1595   @this = use_server(ds.where(pk_hash))
1596 end

Runs set with the passed hash and then runs save_changes.

artist.update(name: 'Jim') # UPDATE artists SET name = 'Jim' WHERE (id = 1)
[show source]
     # File lib/sequel/model/base.rb
1601 def update(hash)
1602   update_restricted(hash, :default)
1603 end
update_fields(hash, fields, opts=nil)

Update the instance's values by calling set_fields with the arguments, then calls save_changes.

artist.update_fields({name: 'Jim'}, [:name])
# UPDATE artists SET name = 'Jim' WHERE (id = 1)

artist.update_fields({hometown: 'LA'}, [:name])
# UPDATE artists SET name = NULL WHERE (id = 1)
[show source]
     # File lib/sequel/model/base.rb
1613 def update_fields(hash, fields, opts=nil)
1614   set_fields(hash, fields, opts)
1615   save_changes
1616 end
valid?(opts = OPTS)

Validates the object and returns true if no errors are reported.

artist.set(name: 'Valid').valid? # => true
artist.set(name: 'Invalid').valid? # => false
artist.errors.full_messages # => ['name cannot be Invalid']
[show source]
     # File lib/sequel/model/base.rb
1632 def valid?(opts = OPTS)
1633   begin
1634     _valid?(opts)
1635   rescue HookFailed
1636     false
1637   end
1638 end

Validates the object. If the object is invalid, errors should be added to the errors attribute. By default, does nothing, as all models are valid by default. See the “Model Validations” guide. for details about validation. Should not be called directly by user code, call valid? instead to check if an object is valid.

[show source]
     # File lib/sequel/model/base.rb
1624 def validate
1625 end