Module: Sequel

Extended by:
NamedTimezones, ThreadLocalTimezones, Timezones
Includes:
SQL::Constants
Defined in:
lib/sequel/core.rb,
lib/sequel/sql.rb,
lib/sequel/model.rb,
lib/sequel/dataset.rb,
lib/sequel/version.rb,
lib/sequel/database.rb,
lib/sequel/timezones.rb,
lib/sequel/exceptions.rb,
lib/sequel/model/base.rb,
lib/sequel/adapters/do.rb,
lib/sequel/dataset/sql.rb,
lib/sequel/adapters/ado.rb,
lib/sequel/adapters/db2.rb,
lib/sequel/adapters/dbi.rb,
lib/sequel/dataset/misc.rb,
lib/sequel/model/errors.rb,
lib/sequel/plugins/list.rb,
lib/sequel/plugins/tree.rb,
lib/sequel/adapters/jdbc.rb,
lib/sequel/adapters/mock.rb,
lib/sequel/adapters/odbc.rb,
lib/sequel/database/misc.rb,
lib/sequel/dataset/graph.rb,
lib/sequel/dataset/query.rb,
lib/sequel/model/plugins.rb,
lib/sequel/plugins/touch.rb,
lib/sequel/adapters/ibmdb.rb,
lib/sequel/adapters/mysql.rb,
lib/sequel/adapters/swift.rb,
lib/sequel/database/query.rb,
lib/sequel/plugins/schema.rb,
lib/sequel/adapters/mysql2.rb,
lib/sequel/adapters/oracle.rb,
lib/sequel/adapters/sqlite.rb,
lib/sequel/ast_transformer.rb,
lib/sequel/dataset/actions.rb,
lib/sequel/metaprogramming.rb,
lib/sequel/plugins/caching.rb,
lib/sequel/adapters/jdbc/h2.rb,
lib/sequel/adapters/tinytds.rb,
lib/sequel/database/dataset.rb,
lib/sequel/database/logging.rb,
lib/sequel/dataset/features.rb,
lib/sequel/dataset/mutation.rb,
lib/sequel/extensions/query.rb,
lib/sequel/model/exceptions.rb,
lib/sequel/plugins/sharding.rb,
lib/sequel/adapters/do/mysql.rb,
lib/sequel/adapters/firebird.rb,
lib/sequel/adapters/informix.rb,
lib/sequel/adapters/jdbc/db2.rb,
lib/sequel/adapters/odbc/db2.rb,
lib/sequel/adapters/openbase.rb,
lib/sequel/adapters/postgres.rb,
lib/sequel/extensions/to_dot.rb,
lib/sequel/model/inflections.rb,
lib/sequel/plugins/rcte_tree.rb,
lib/sequel/adapters/ado/mssql.rb,
lib/sequel/adapters/do/sqlite.rb,
lib/sequel/adapters/jdbc/jtds.rb,
lib/sequel/model/associations.rb,
lib/sequel/plugins/subclasses.rb,
lib/sequel/plugins/timestamps.rb,
lib/sequel/adapters/amalgalite.rb,
lib/sequel/adapters/jdbc/as400.rb,
lib/sequel/adapters/jdbc/derby.rb,
lib/sequel/adapters/jdbc/mssql.rb,
lib/sequel/adapters/jdbc/mysql.rb,
lib/sequel/adapters/odbc/mssql.rb,
lib/sequel/adapters/shared/db2.rb,
lib/sequel/database/connecting.rb,
lib/sequel/extensions/sql_expr.rb,
lib/sequel/plugins/composition.rb,
lib/sequel/adapters/do/postgres.rb,
lib/sequel/adapters/jdbc/hsqldb.rb,
lib/sequel/adapters/jdbc/oracle.rb,
lib/sequel/adapters/jdbc/sqlite.rb,
lib/sequel/adapters/swift/mysql.rb,
lib/sequel/extensions/migration.rb,
lib/sequel/plugins/active_model.rb,
lib/sequel/plugins/identity_map.rb,
lib/sequel/adapters/shared/mssql.rb,
lib/sequel/adapters/shared/mysql.rb,
lib/sequel/adapters/swift/sqlite.rb,
lib/sequel/extensions/pagination.rb,
lib/sequel/plugins/serialization.rb,
lib/sequel/adapters/jdbc/firebird.rb,
lib/sequel/adapters/jdbc/informix.rb,
lib/sequel/adapters/shared/access.rb,
lib/sequel/adapters/shared/oracle.rb,
lib/sequel/adapters/shared/sqlite.rb,
lib/sequel/plugins/force_encoding.rb,
lib/sequel/plugins/instance_hooks.rb,
lib/sequel/plugins/xml_serializer.rb,
lib/sequel/adapters/jdbc/sqlserver.rb,
lib/sequel/adapters/swift/postgres.rb,
lib/sequel/database/schema_methods.rb,
lib/sequel/extensions/pretty_table.rb,
lib/sequel/plugins/association_pks.rb,
lib/sequel/plugins/boolean_readers.rb,
lib/sequel/plugins/defaults_setter.rb,
lib/sequel/plugins/json_serializer.rb,
lib/sequel/plugins/lazy_attributes.rb,
lib/sequel/plugins/string_stripper.rb,
lib/sequel/adapters/jdbc/postgresql.rb,
lib/sequel/adapters/shared/firebird.rb,
lib/sequel/adapters/shared/informix.rb,
lib/sequel/adapters/shared/postgres.rb,
lib/sequel/adapters/shared/progress.rb,
lib/sequel/extensions/schema_dumper.rb,
lib/sequel/plugins/instance_filters.rb,
lib/sequel/plugins/typecast_on_load.rb,
lib/sequel/database/dataset_defaults.rb,
lib/sequel/database/schema_generator.rb,
lib/sequel/model/default_inflections.rb,
lib/sequel/plugins/many_through_many.rb,
lib/sequel/plugins/nested_attributes.rb,
lib/sequel/adapters/jdbc/transactions.rb,
lib/sequel/extensions/named_timezones.rb,
lib/sequel/plugins/hook_class_methods.rb,
lib/sequel/plugins/optimistic_locking.rb,
lib/sequel/plugins/update_primary_key.rb,
lib/sequel/plugins/validation_helpers.rb,
lib/sequel/dataset/prepared_statements.rb,
lib/sequel/plugins/association_proxies.rb,
lib/sequel/plugins/prepared_statements.rb,
lib/sequel/plugins/skip_create_refresh.rb,
lib/sequel/plugins/dataset_associations.rb,
lib/sequel/extensions/looser_typecasting.rb,
lib/sequel/plugins/tactical_eager_loading.rb,
lib/sequel/plugins/class_table_inheritance.rb,
lib/sequel/adapters/utils/stored_procedures.rb,
lib/sequel/extensions/columns_introspection.rb,
lib/sequel/plugins/association_dependencies.rb,
lib/sequel/plugins/prepared_statements_safe.rb,
lib/sequel/plugins/single_table_inheritance.rb,
lib/sequel/plugins/validation_class_methods.rb,
lib/sequel/extensions/thread_local_timezones.rb,
lib/sequel/plugins/association_autoreloading.rb,
lib/sequel/plugins/prepared_statements_with_pk.rb,
lib/sequel/plugins/prepared_statements_associations.rb,
lib/sequel/adapters/shared/mysql_prepared_statements.rb,
lib/sequel/plugins/serialization_modification_detection.rb,
lib/sequel/adapters/utils/emulate_offset_with_row_number.rb

Overview

The thread_local_timezones extension allows you to set a per-thread timezone that will override the default global timezone while the thread is executing. The main use case is for web applications that execute each request in its own thread, and want to set the timezones based on the request. The most common example is having the database always store time in UTC, but have the application deal with the timezone of the current user. That can be done with:

Sequel.database_timezone = :utc
# In each thread:
Sequel.thread_application_timezone = current_user.timezone

This extension is designed to work with the named_timezones extension.

This extension adds the thread_application_timezone=, thread_database_timezone=, and thread_typecast_timezone= methods to the Sequel module. It overrides the application_timezone, database_timezone, and typecast_timezone methods to check the related thread local timezone first, and use it if present. If the related thread local timezone is not present, it falls back to the default global timezone.

There is one special case of note. If you have a default global timezone and you want to have a nil thread local timezone, you have to set the thread local value to :nil instead of nil:

Sequel.application_timezone = :utc
Sequel.thread_application_timezone = nil
Sequel.application_timezone # => :utc
Sequel.thread_application_timezone = :nil
Sequel.application_timezone # => nil

Defined Under Namespace

Modules: ADO, Access, Amalgalite, ColumnsIntrospection, DB2, DBI, DataObjects, EmulateOffsetWithRowNumber, Firebird, IBMDB, Inflections, Informix, JDBC, LooserTypecasting, MSSQL, Metaprogramming, Mock, MySQL, Mysql2, NamedTimezones, ODBC, OpenBase, Oracle, Plugins, Postgres, PrettyTable, Progress, SQL, SQLite, Schema, Swift, ThreadLocalTimezones, Timezones, TinyTDS Classes: ASTTransformer, AdapterNotFound, BasicObject, ConnectionPool, Database, DatabaseConnectionError, DatabaseDisconnectError, DatabaseError, Dataset, Error, HookFailed, IntegerMigrator, InvalidOperation, InvalidValue, LiteralString, Migration, MigrationAlterTableReverser, MigrationDSL, MigrationReverser, Migrator, Model, NoExistingObject, NotImplemented, PoolTimeout, Qualifier, Rollback, SQLTime, ShardedSingleConnectionPool, ShardedThreadedConnectionPool, SimpleMigration, SingleConnectionPool, ThreadedConnectionPool, TimestampMigrator, ToDot, UnbindDuplicate, Unbinder, UndefinedAssociation, ValidationFailed

Constant Summary collapse

MAJOR =

The major version of Sequel. Only bumped for major changes.

3
MINOR =

The minor version of Sequel. Bumped for every non-patch level release, generally around once a month.

32
TINY =

The tiny version of Sequel. Usually 0, only bumped for bugfix releases that fix regressions from previous versions.

0
VERSION =

The version of Sequel you are using, as a string (e.g. “2.11.0”)

[MAJOR, MINOR, TINY].join('.')
ADAPTER_MAP =

Hash of adapters that have been used. The key is the adapter scheme symbol, and the value is the Database subclass.

{}
DATABASES =

Array of all databases to which Sequel has connected. If you are developing an application that can connect to an arbitrary number of databases, delete the database objects from this or they will not get garbage collected.

[]
BeforeHookFailed =

Deprecated alias for HookFailed, kept for backwards compatibility

HookFailed
DEFAULT_INFLECTIONS_PROC =

Proc that is instance evaled to create the default inflections for both the model inflector and the inflector extension.

proc do
  plural(/$/, 's')
  plural(/s$/i, 's')
  plural(/(alias|(?:stat|octop|vir|b)us)$/i, '\1es')
  plural(/(buffal|tomat)o$/i, '\1oes')
  plural(/([ti])um$/i, '\1a')
  plural(/sis$/i, 'ses')
  plural(/(?:([^f])fe|([lr])f)$/i, '\1\2ves')
  plural(/(hive)$/i, '\1s')
  plural(/([^aeiouy]|qu)y$/i, '\1ies')
  plural(/(x|ch|ss|sh)$/i, '\1es')
  plural(/(matr|vert|ind)ix|ex$/i, '\1ices')
  plural(/([m|l])ouse$/i, '\1ice')

  singular(/s$/i, '')
  singular(/([ti])a$/i, '\1um')
  singular(/(analy|ba|cri|diagno|parenthe|progno|synop|the)ses$/i, '\1sis')
  singular(/([^f])ves$/i, '\1fe')
  singular(/([h|t]ive)s$/i, '\1')
  singular(/([lr])ves$/i, '\1f')
  singular(/([^aeiouy]|qu)ies$/i, '\1y')
  singular(/(m)ovies$/i, '\1ovie')
  singular(/(x|ch|ss|sh)es$/i, '\1')
  singular(/([m|l])ice$/i, '\1ouse')
  singular(/buses$/i, 'bus')
  singular(/oes$/i, 'o')
  singular(/shoes$/i, 'shoe')
  singular(/(alias|(?:stat|octop|vir|b)us)es$/i, '\1')
  singular(/(vert|ind)ices$/i, '\1ex')
  singular(/matrices$/i, 'matrix')

  irregular('person', 'people')
  irregular('man', 'men')
  irregular('child', 'children')
  irregular('sex', 'sexes')
  irregular('move', 'moves')
  irregular('quiz', 'quizzes')
  irregular('testis', 'testes')

  uncountable(%w(equipment information rice money species series fish sheep news))
end

Constants included from SQL::Constants

SQL::Constants::CURRENT_DATE, SQL::Constants::CURRENT_TIME, SQL::Constants::CURRENT_TIMESTAMP, SQL::Constants::NOTNULL, SQL::Constants::NULL, SQL::Constants::SQLFALSE, SQL::Constants::SQLTRUE

Class Attribute Summary collapse

Attributes included from Timezones

#application_timezone, #database_timezone, #typecast_timezone

Class Method Summary collapse

Methods included from Timezones

application_to_database_timestamp, convert_output_timestamp, convert_timestamp, database_to_application_timestamp, default_timezone=, typecast_to_application_timestamp

Class Attribute Details

.convert_two_digit_years ⇒ Object

Sequel converts two digit years in Dates and DateTimes by default, so 01/02/03 is interpreted at January 2nd, 2003, and 12/13/99 is interpreted as December 13, 1999. You can override this to treat those dates as January 2nd, 0003 and December 13, 0099, respectively, by:

Sequel.convert_two_digit_years = false



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# File 'lib/sequel/core.rb', line 42

def convert_two_digit_years
  @convert_two_digit_years
end

.datetime_class ⇒ Object

Sequel can use either Time or DateTime for times returned from the database. It defaults to Time. To change it to DateTime:

Sequel.datetime_class = DateTime

For ruby versions less than 1.9.2, Time has a limited range (1901 to 2038), so if you use datetimes out of that range, you need to switch to DateTime. Also, before 1.9.2, Time can only handle local and UTC times, not other timezones. Note that Time and DateTime objects have a different API, and in cases where they implement the same methods, they often implement them differently (e.g. + using seconds on Time and days on DateTime).



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# File 'lib/sequel/core.rb', line 56

def datetime_class
  @datetime_class
end

.empty_array_handle_nulls ⇒ Object

Sets whether or not to attempt to handle NULL values correctly when given an empty array. By default:

DB[:a].filter(:b=>[])
# SELECT * FROM a WHERE (b != b)
DB[:a].exclude(:b=>[])
# SELECT * FROM a WHERE (b = b)

However, some databases (e.g. MySQL) will perform very poorly with this type of query. You can set this to false to get the following behavior:

DB[:a].filter(:b=>[])
# SELECT * FROM a WHERE 1 = 0
DB[:a].exclude(:b=>[])
# SELECT * FROM a WHERE 1 = 1

This may not handle NULLs correctly, but can be much faster on some databases.



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# File 'lib/sequel/core.rb', line 77

def empty_array_handle_nulls
  @empty_array_handle_nulls
end

.virtual_row_instance_eval ⇒ Object

For backwards compatibility, has no effect.



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# File 'lib/sequel/core.rb', line 80

def virtual_row_instance_eval
  @virtual_row_instance_eval
end

Class Method Details

.condition_specifier?(obj) ⇒ Boolean

Returns true if the passed object could be a specifier of conditions, false otherwise. Currently, Sequel considers hashes and arrays of two element arrays as condition specifiers.

Sequel.condition_specifier?({}) # => true
Sequel.condition_specifier?([[1, 2]]) # => true
Sequel.condition_specifier?([]) # => false
Sequel.condition_specifier?([1]) # => false
Sequel.condition_specifier?(1) # => false

Returns:

  • (Boolean) 


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# File 'lib/sequel/core.rb', line 111

def self.condition_specifier?(obj)
  case obj
  when Hash
    true
  when Array
    !obj.empty? && !obj.is_a?(SQL::ValueList) && obj.all?{|i| (Array === i) && (i.length == 2)}
  else
    false
  end
end

.connect(*args, &block) ⇒ Object

Creates a new database object based on the supplied connection string and optional arguments. The specified scheme determines the database class used, and the rest of the string specifies the connection options. For example:

DB = Sequel.connect('sqlite:/') # Memory database
DB = Sequel.connect('sqlite://blog.db') # ./blog.db
DB = Sequel.connect('sqlite:///blog.db') # /blog.db
DB = Sequel.connect('postgres://user:password@host:port/database_name')
DB = Sequel.connect('sqlite:///blog.db', :max_connections=>10)

If a block is given, it is passed the opened Database object, which is closed when the block exits. For example:

Sequel.connect('sqlite://blog.db'){|db| puts db[:users].count}

For details, see the “Connecting to a Database” guide. To set up a master/slave or sharded database connection, see the “Master/Slave Databases and Sharding” guide.



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# File 'lib/sequel/core.rb', line 140

def self.connect(*args, &block)
  Database.connect(*args, &block)
end

.convert_exception_class(exception, klass) ⇒ Object

Convert the exception to the given class. The given class should be Sequel::Error or a subclass. Returns an instance of klass with the message and backtrace of exception.



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# File 'lib/sequel/core.rb', line 147

def self.convert_exception_class(exception, klass)
  return exception if exception.is_a?(klass)
  e = klass.new("#{exception.class}: #{exception.message}")
  e.wrapped_exception = exception
  e.set_backtrace(exception.backtrace)
  e
end

.extension(*extensions) ⇒ Object

Load all Sequel extensions given. Extensions are just files that exist under sequel/extensions in the load path, and are just required. Generally, extensions modify the behavior of Database and/or Dataset, but Sequel ships with some extensions that modify other classes that exist for backwards compatibility. In some cases, requiring an extension modifies classes directly, and in others, it just loads a module that you can extend other classes with. Consult the documentation for each extension you plan on using for usage.

Sequel.extension(:schema_dumper)
Sequel.extension(:pagination, :query)



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# File 'lib/sequel/core.rb', line 165

def self.extension(*extensions)
  extensions.each{|e| tsk_require "sequel/extensions/#{e}"}
end

.identifier_input_method=(value) ⇒ Object

Set the method to call on identifiers going into the database. This affects the literalization of identifiers by calling this method on them before they are input. Sequel upcases identifiers in all SQL strings for most databases, so to turn that off:

Sequel.identifier_input_method = nil

to downcase instead:

Sequel.identifier_input_method = :downcase

Other String instance methods work as well.



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# File 'lib/sequel/core.rb', line 180

def self.identifier_input_method=(value)
  Database.identifier_input_method = value
end

.identifier_output_method=(value) ⇒ Object

Set the method to call on identifiers coming out of the database. This affects the literalization of identifiers by calling this method on them when they are retrieved from the database. Sequel downcases identifiers retrieved for most databases, so to turn that off:

Sequel.identifier_output_method = nil

to upcase instead:

Sequel.identifier_output_method = :upcase

Other String instance methods work as well.



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# File 'lib/sequel/core.rb', line 196

def self.identifier_output_method=(value)
  Database.identifier_output_method = value
end

.inflections {|Inflections| ... } ⇒ Object

Yield the Inflections module if a block is given, and return the Inflections module.

Yields:



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# File 'lib/sequel/model/inflections.rb', line 4

def self.inflections
  yield Inflections if block_given?
  Inflections
end

.k_require ⇒ Object

Alias to the standard version of require



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# File 'lib/sequel/core.rb', line 83

alias k_require require

.migration(&block) ⇒ Object

The preferred method for writing Sequel migrations, using a DSL:

Sequel.migration do
  up do
    create_table(:artists) do
      primary_key :id
      String :name
    end
  end

  down do
    drop_table(:artists)
  end
end

Designed to be used with the Migrator class, part of the migration extension.



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# File 'lib/sequel/extensions/migration.rb', line 241

def self.migration(&block)
  MigrationDSL.create(&block)
end

.Model(source) ⇒ Object

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 implicit name. This is neater than using set_dataset inside the class, doesn’t require a bogus query for the schema.

# 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



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# File 'lib/sequel/model.rb', line 37

def self.Model(source)
  Model::ANONYMOUS_MODEL_CLASSES[source] ||= if source.is_a?(Database)
    c = Class.new(Model)
    c.db = source
    c
  else
    Class.new(Model).set_dataset(source)
  end
end

.quote_identifiers=(value) ⇒ Object

Set whether to quote identifiers for all databases by default. By default, Sequel quotes identifiers in all SQL strings, so to turn that off:

Sequel.quote_identifiers = false



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# File 'lib/sequel/core.rb', line 204

def self.quote_identifiers=(value)
  Database.quote_identifiers = value
end

.require(files, subdir = nil) ⇒ Object

Require all given files which should be in the same or a subdirectory of this file. If a subdir is given, assume all files are in that subdir. This is used to ensure that the files loaded are from the same version of Sequel as this file.



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# File 'lib/sequel/core.rb', line 212

def self.require(files, subdir=nil)
  Array(files).each{|f| super("#{File.dirname(__FILE__).untaint}/#{"#{subdir}/" if subdir}#{f}")}
end

.single_threaded=(value) ⇒ Object

Set whether to set the single threaded mode for all databases by default. By default, Sequel uses a thread-safe connection pool, which isn’t as fast as the single threaded connection pool. If your program will only have one thread, and speed is a priority, you may want to set this to true:

Sequel.single_threaded = true



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# File 'lib/sequel/core.rb', line 222

def self.single_threaded=(value)
  Database.single_threaded = value
end

.string_to_date(string) ⇒ Object

Converts the given string into a Date object.

Sequel.string_to_date('2010-09-10') # Date.civil(2010, 09, 10)



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# File 'lib/sequel/core.rb', line 229

def self.string_to_date(string)
  begin
    Date.parse(string, Sequel.convert_two_digit_years)
  rescue => e
    raise convert_exception_class(e, InvalidValue)
  end
end

.string_to_datetime(string) ⇒ Object

Converts the given string into a Time or DateTime object, depending on the value of Sequel.datetime_class.

Sequel.string_to_datetime('2010-09-10 10:20:30') # Time.local(2010, 09, 10, 10, 20, 30)



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# File 'lib/sequel/core.rb', line 241

def self.string_to_datetime(string)
  begin
    if datetime_class == DateTime
      DateTime.parse(string, convert_two_digit_years)
    else
      datetime_class.parse(string)
    end
  rescue => e
    raise convert_exception_class(e, InvalidValue)
  end
end

.string_to_time(string) ⇒ Object

Converts the given string into a Sequel::SQLTime object.

v = Sequel.string_to_time('10:20:30') # Sequel::SQLTime.parse('10:20:30')
DB.literal(v) # => '10:20:30'



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# File 'lib/sequel/core.rb', line 257

def self.string_to_time(string)
  begin
    SQLTime.parse(string)
  rescue => e
    raise convert_exception_class(e, InvalidValue)
  end
end

.transaction(dbs, opts = {}, &block) ⇒ Object

Uses a transaction on all given databases with the given options. This:

Sequel.transaction([DB1, DB2, DB3]){...}

is equivalent to:

DB1.transaction do
  DB2.transaction do
    DB3.transaction do
      ...
    end
  end
end

except that if Sequel::Rollback is raised by the block, the transaction is rolled back on all databases instead of just the last one.

Note that this method cannot guarantee that all databases will commit or rollback. For example, if DB3 commits but attempting to commit on DB2 fails (maybe because foreign key checks are deferred), there is no way to uncommit the changes on DB3. For that kind of support, you need to have two-phase commit/prepared transactions (which Sequel supports on some databases).



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# File 'lib/sequel/core.rb', line 288

def self.transaction(dbs, opts={}, &block)
  unless opts[:rollback]
    rescue_rollback = true
    opts = opts.merge(:rollback=>:reraise)
  end
  pr = dbs.reverse.inject(block){|bl, db| proc{db.transaction(opts, &bl)}}
  if rescue_rollback
    begin
      pr.call
    rescue Sequel::Rollback => e
      nil
    end
  else
    pr.call
  end
end

.ts_require(*args) ⇒ Object

Same as Sequel.require, but wrapped in a mutex in order to be thread safe.



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# File 'lib/sequel/core.rb', line 306

def self.ts_require(*args)
  check_requiring_thread{require(*args)}
end

.tsk_require(*args) ⇒ Object

Same as Kernel.require, but wrapped in a mutex in order to be thread safe.



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# File 'lib/sequel/core.rb', line 311

def self.tsk_require(*args)
  check_requiring_thread{k_require(*args)}
end

.version ⇒ Object

The version of Sequel you are using, as a string (e.g. “2.11.0”)



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# File 'lib/sequel/version.rb', line 15

def self.version
  VERSION
end

.virtual_row(&block) ⇒ Object

If the supplied block takes a single argument, yield a new SQL::VirtualRow instance to the block argument. Otherwise, evaluate the block in the context of a new SQL::VirtualRow instance.

Sequel.virtual_row{a} # Sequel::SQL::Identifier.new(:a)
Sequel.virtual_row{|o| o.a{}} # Sequel::SQL::Function.new(:a)



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# File 'lib/sequel/core.rb', line 322

def self.virtual_row(&block)
  vr = SQL::VirtualRow.new
  case block.arity
  when -1, 0
    vr.instance_eval(&block)
  else
    block.call(vr)
  end  
end