module Sequel::SequelMethods

  1. lib/sequel/core.rb
  2. lib/sequel/timezones.rb
  3. show all

Sequel doesn’t pay much attention to timezones by default, but you can set it to handle timezones if you want. There are three separate timezone settings:

All three timezones have getter and setter methods. You can set all three timezones to the same value at once via Sequel.default_timezone=.

The only timezone values that are supported by default are :utc (convert to UTC), :local (convert to local time), and nil (don’t convert). If you need to convert to a specific timezone, or need the timezones being used to change based on the environment (e.g. current user), you need to use the named_timezones extension (and use DateTime as the datetime_class). Sequel also ships with a thread_local_timezones extensions which allows each thread to have its own timezone values for each of the timezones.

Attributes

application_timezone [R]

The timezone you want the application to use. This is the timezone that incoming times from the database and typecasting are converted to.

convert_two_digit_years [R]

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

The setter method is deprecated and will be removed in Sequel 6. The reader method will be deprecated in Sequel 6.0 and removed in Sequel 6.1.

database_timezone [R]

The timezone for storage in the database. This is the timezone to which Sequel will convert timestamps before literalizing them for storage in the database. It is also the timezone that Sequel will assume database timestamp values are already in (if they don’t include an offset).

datetime_class [R]

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

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).

The setter method is deprecated and will be removed in Sequel 6. The reader method will be deprecated in Sequel 6.0 and removed in Sequel 6.1.

single_threaded [RW]

Set whether Sequel is being used in single threaded mode. By default, Sequel uses a thread-safe connection pool, which isn’t as fast as the single threaded connection pool, and also has some additional thread safety checks. If your program will only have one thread, and speed is a priority, you should set this to true:

Sequel.single_threaded = true
typecast_timezone [R]

The timezone that incoming data that Sequel needs to typecast is assumed to be already in (if they don’t include an offset).

Public Instance methods

application_to_database_timestamp(v)

Convert the given Time/DateTime object into the database timezone, used when literalizing objects in an SQL string.

[show source]
   # File lib/sequel/timezones.rb
50 def application_to_database_timestamp(v)
51   convert_output_timestamp(v, Sequel.database_timezone)
52 end
array_or_set_join(obj, arg)

Join the array or set.

This method is deprecated and will be removed in Sequel 6.1.

[show source]
    # File lib/sequel/core.rb
200 def array_or_set_join(obj, arg) # SEQUEL6.1: Remove
201   obj.join(arg)
202 end
condition_specifier?(obj)

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
[show source]
    # File lib/sequel/core.rb
102 def condition_specifier?(obj)
103   case obj
104   when Hash
105     true
106   when Array
107     !obj.empty? && !obj.is_a?(SQL::ValueList) && obj.all?{|i| i.is_a?(Array) && (i.length == 2)}
108   else
109     false
110   end
111 end
connect(*args, &block)

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)

You can also pass a single options hash:

DB = Sequel.connect(adapter: 'sqlite', database: './blog.db')

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}

If a block is not given, a reference to this database will be held in Sequel::DATABASES until it is removed manually. This is by design, and used by Sequel::Model to pick the default database. It is recommended to pass a block if you do not want the resulting Database object to remain in memory until the process terminates, or use the keep_reference: false Database option.

For details, see the “Connecting to a Database” guide. To set up a primary/replica or sharded database connection, see the “Primary/Replica Database Configurations and Sharding” guide.

[show source]
    # File lib/sequel/core.rb
142 def connect(*args, &block)
143   Database.connect(*args, &block)
144 end
convert_exception_class(exception, klass)

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.

[show source]
    # File lib/sequel/core.rb
155 def convert_exception_class(exception, klass)
156   return exception if exception.is_a?(klass)
157   e = klass.new("#{exception.class}: #{exception.message}")
158   e.wrapped_exception = exception
159   e.set_backtrace(exception.backtrace)
160   e
161 end
convert_output_timestamp(v, output_timezone)

Converts the object to the given output_timezone.

[show source]
   # File lib/sequel/timezones.rb
55 def convert_output_timestamp(v, output_timezone)
56   if output_timezone
57     if v.is_a?(DateTime)
58       case output_timezone
59       when :utc
60         v.new_offset(0)
61       when :local
62         v.new_offset(local_offset_for_datetime(v))
63       else
64         convert_output_datetime_other(v, output_timezone)
65       end
66     else
67       case output_timezone
68       when :utc
69         v.getutc
70       when :local
71         v.getlocal
72       else
73         convert_output_time_other(v, output_timezone)
74       end
75     end
76   else
77     v
78   end
79 end
convert_timestamp(v, input_timezone)

Converts the given object from the given input timezone to the application_timezone using convert_input_timestamp and convert_output_timestamp.

[show source]
   # File lib/sequel/timezones.rb
84 def convert_timestamp(v, input_timezone)
85   if v.is_a?(Date) && !v.is_a?(DateTime)
86     # Dates handled specially as they are assumed to already be in the application_timezone
87     if datetime_class == DateTime
88       DateTime.civil(v.year, v.month, v.day, 0, 0, 0, application_timezone == :local ? Rational(Time.local(v.year, v.month, v.day).utc_offset, 86400) : 0)
89     else
90       Time.public_send(application_timezone == :utc ? :utc : :local, v.year, v.month, v.day)
91     end
92   else
93     convert_output_timestamp(convert_input_timestamp(v, input_timezone), application_timezone)
94   end
95 rescue InvalidValue
96   raise
97 rescue => e
98   raise convert_exception_class(e, InvalidValue)
99 end
convert_two_digit_years=(v)
[show source]
   # File lib/sequel/core.rb
56 def convert_two_digit_years=(v)
57   Sequel::Deprecation.deprecate("Sequel.convert_two_digit_years= is deprecated and will be removed in Sequel 6.")
58   @convert_two_digit_years = v
59 end
core_extensions?()

Assume the core extensions are not loaded by default, if the core_extensions extension is loaded, this will be overridden.

[show source]
    # File lib/sequel/core.rb
148 def core_extensions?
149   false
150 end
current()

The current concurrency primitive, Thread.current by default.

[show source]
    # File lib/sequel/core.rb
164 def current
165   Thread.current
166 end
database_to_application_timestamp(v)

Convert the given object into an object of Sequel.datetime_class in the application_timezone. Used when converting datetime/timestamp columns returned by the database.

[show source]
    # File lib/sequel/timezones.rb
104 def database_to_application_timestamp(v)
105   convert_timestamp(v, Sequel.database_timezone)
106 end
datetime_class=(v)
[show source]
   # File lib/sequel/core.rb
75 def datetime_class=(v)
76   Sequel::Deprecation.deprecate("Sequel.datetime_class= is deprecated and will be removed in Sequel 6.")
77   @datetime_class = v
78 end
default_timezone=(tz)

Sets the database, application, and typecasting timezones to the given timezone.

[show source]
    # File lib/sequel/timezones.rb
109 def default_timezone=(tz)
110   self.database_timezone = tz
111   self.application_timezone = tz
112   self.typecast_timezone = tz
113 end
elapsed_seconds_since(timer)

The elapsed seconds since the given timer object was created. The timer object should have been created via Sequel.start_timer.

This method is deprecated and will be removed in Sequel 6.1 (or potentially in 6.0 if Ruby 2.1 support is dropped before 6.0).

[show source]
    # File lib/sequel/core.rb
418 def elapsed_seconds_since(timer) # SEQUEL6.1: Remove
419   start_timer - timer
420 end
extension(*extensions)

Load all Sequel extensions given. Extensions are just files that exist under sequel/extensions in the load path, and are just required.

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(:blank)
Sequel.extension(:core_extensions, :named_timezones)
[show source]
    # File lib/sequel/core.rb
176 def extension(*extensions)
177   extensions.each do |e|
178     e = e.to_s
179 
180     if %r{..[/\\]} =~ e
181       raise Error, "cannot use extension with ../ for security reasons"
182     end
183 
184     Kernel.require("sequel/extensions/#{e}")
185   end
186 end
json_parser_error_class()

The exception class raised if there is an error parsing JSON. This can be overridden to use an alternative json implementation.

This method is deprecated and will be removed in Sequel 6.1.

[show source]
    # File lib/sequel/core.rb
192 def json_parser_error_class # SEQUEL6.1: Remove
193   JSON::ParserError
194 end
object_to_json(obj, *args, &block)

Convert given object to json and return the result. This can be overridden to use an alternative json implementation.

This method is deprecated and will be removed in Sequel 6.1.

[show source]
    # File lib/sequel/core.rb
231 def object_to_json(obj, *args, &block) # SEQUEL6.1: Remove
232   obj.to_json(*args, &block)
233 end
parse_json(json)

Parse the string as JSON and return the result. This can be overridden to use an alternative json implementation.

This method is deprecated and will be removed in Sequel 6.1.

[show source]
    # File lib/sequel/core.rb
239 def parse_json(json) # SEQUEL6.1: Remove
240   if JSON::VERSION >= '3'
241     JSON.parse(json)
242   else
243     JSON.parse(json, :create_additions=>false)
244   end
245 end
recursive_map(array, converter)

Convert each item in the array to the correct type, handling multi-dimensional arrays. For each element in the array or subarrays, call the converter, unless the value is nil.

[show source]
    # File lib/sequel/core.rb
261 def recursive_map(array, converter)
262   array.map do |i|
263     if i.is_a?(Array)
264       recursive_map(i, converter)
265     elsif !i.nil?
266       converter.call(i)
267     end
268   end
269 end
require(files, subdir=nil)

For backwards compatibility only. require_relative should be used instead.

[show source]
    # File lib/sequel/core.rb
272 def require(files, subdir=nil)
273   # SEQUEL6: Remove
274   # Use Kernel.require_relative to work around JRuby 9.0 bug
275   # simplecov:disable
276   Array(files).each{|f| Kernel.require_relative "#{"#{subdir}/" if subdir}#{f}"}
277   # simplecov:enable
278   Sequel::Deprecation.deprecate("Sequel.require is deprecated and will be removed in Sequel 6.")
279 end
set_temp_name(mod)

Create a new module using the block, and set the temporary name on it using the given a containing module and name.

[show source]
    # File lib/sequel/core.rb
215 def set_temp_name(mod)
216   mod.set_temporary_name(yield)
217   mod
218 end
split_symbol(sym)

Splits the symbol into three parts, if symbol splitting is enabled (not the default). Each part will either be a string or nil. If symbol splitting is disabled, returns an array with the first and third parts being nil, and the second part behind a string version of the symbol.

For columns, these parts are the table, column, and alias. For tables, these parts are the schema, table, and alias.

[show source]
    # File lib/sequel/core.rb
288 def split_symbol(sym)
289   # SEQUEL6.1: Remove
290   unless v = Sequel.synchronize{SPLIT_SYMBOL_CACHE_[sym]}
291     if split_symbols?
292       v = case s = sym.to_s
293       when /\A((?:(?!__).)+)__((?:(?!___).)+)___(.+)\z/
294         [$1.freeze, $2.freeze, $3.freeze].freeze
295       when /\A((?:(?!___).)+)___(.+)\z/
296         [nil, $1.freeze, $2.freeze].freeze
297       when /\A((?:(?!__).)+)__(.+)\z/
298         [$1.freeze, $2.freeze, nil].freeze
299       else
300         [nil, s.freeze, nil].freeze
301       end
302     else
303       v = [nil,sym.to_s.freeze,nil].freeze
304     end
305     Sequel.synchronize{SPLIT_SYMBOL_CACHE_[sym] = v}
306   end
307   v
308 end
split_symbols=(v)

Setting this to true enables Sequel’s historical behavior of splitting symbols on double or triple underscores:

:table__column         # table.column
:column___alias        # column AS alias
:table__column___alias # table.column AS alias

It is only recommended to turn this on for backwards compatibility until such symbols have been converted to use newer Sequel APIs such as:

Sequel[:table][:column]            # table.column
Sequel[:column].as(:alias)         # column AS alias
Sequel[:table][:column].as(:alias) # table.column AS alias

Sequel::Database instances do their own caching of literalized symbols, and changing this setting does not affect those caches. It is recommended that if you want to change this setting, you do so directly after requiring Sequel, before creating any Sequel::Database instances.

Disabling symbol splitting will also disable the handling of double underscores in virtual row methods, causing such methods to yield regular identifiers instead of qualified identifiers:

# Sequel.split_symbols = true
Sequel.expr{table__column}  # table.column
Sequel.expr{table[:column]} # table.column

# Sequel.split_symbols = false
Sequel.expr{table__column}  # table__column
Sequel.expr{table[:column]} # table.column
[show source]
    # File lib/sequel/core.rb
340 def split_symbols=(v)
341   Sequel::Deprecation.deprecate("Sequel.split_symbols= is deprecated and will be removed in Sequel 6.")
342   Sequel.synchronize{SPLIT_SYMBOL_CACHE_.clear}
343   @split_symbols = v
344 end
split_symbols?()

Whether Sequel currently splits symbols into qualified/aliased identifiers.

[show source]
    # File lib/sequel/core.rb
347 def split_symbols?
348   # SEQUEL6.1: Remove
349   @split_symbols
350 end
start_timer()

A timer object that can be passed to Sequel.elapsed_seconds_since to return the number of seconds elapsed.

This method is deprecated and will be removed in Sequel 6.1 (or potentially in 6.0 if Ruby 2.1 support is dropped before 6.0).

[show source]
    # File lib/sequel/core.rb
402 def start_timer # SEQUEL6.1: Remove
403   Process.clock_gettime(Process::CLOCK_MONOTONIC)
404 end
string_to_date(string)

Converts the given string into a Date object.

Sequel.string_to_date('2010-09-10') # Date.civil(2010, 09, 10)
[show source]
    # File lib/sequel/core.rb
355 def string_to_date(string)
356   Date.parse(string, Sequel.convert_two_digit_years)
357 rescue => e
358   raise convert_exception_class(e, InvalidValue)
359 end
string_to_datetime(string)

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)

This method is deprecated and will be removed in Sequel 6.1.

[show source]
    # File lib/sequel/core.rb
367 def string_to_datetime(string) # SEQUEL6.1: Remove
368   if datetime_class == DateTime
369     DateTime.parse(string, convert_two_digit_years)
370   else
371     datetime_class.parse(string)
372   end
373 rescue => e
374   raise convert_exception_class(e, InvalidValue)
375 end
string_to_time(string)

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'
[show source]
    # File lib/sequel/core.rb
381 def string_to_time(string)
382   SQLTime.parse(string)
383 rescue => e
384   raise convert_exception_class(e, InvalidValue)
385 end
synchronize(&block)

Unless in single threaded mode, protects access to any mutable global data structure in Sequel. Uses a non-reentrant mutex, so calling code should be careful. In general, this should only be used around the minimal possible code such as Hash#[], Hash#[]=, Hash#delete, Array#<<, and Array#delete.

[show source]
    # File lib/sequel/core.rb
392 def synchronize(&block)
393   @single_threaded ? yield : @data_mutex.synchronize(&block)
394 end
synchronize_with(mutex)

If a mutex is given, synchronize access using it. If nil is given, just yield to the block. This is designed for cases where a mutex may or may not be provided.

[show source]
    # File lib/sequel/core.rb
250 def synchronize_with(mutex)
251   if mutex
252     mutex.synchronize{yield}
253   else
254     yield
255   end
256 end
transaction(dbs, opts=OPTS, &block)

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).

[show source]
    # File lib/sequel/core.rb
444 def transaction(dbs, opts=OPTS, &block)
445   unless opts[:rollback]
446     rescue_rollback = true
447     opts = Hash[opts].merge!(:rollback=>:reraise)
448   end
449   pr = dbs.reverse.inject(block){|bl, db| proc{db.transaction(opts, &bl)}}
450   if rescue_rollback
451     begin
452       pr.call
453     rescue Sequel::Rollback
454       nil
455     end
456   else
457     pr.call
458   end
459 end
typecast_to_application_timestamp(v)

Convert the given object into an object of Sequel.datetime_class in the application_timezone. Used when typecasting values when assigning them to model datetime attributes.

[show source]
    # File lib/sequel/timezones.rb
118 def typecast_to_application_timestamp(v)
119   convert_timestamp(v, Sequel.typecast_timezone)
120 end
virtual_row(&block)

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

Sequel.virtual_row{a} # Sequel::SQL::Identifier.new(:a)
Sequel.virtual_row{|o| o.a} # Sequel::SQL::Function.new(:a)
[show source]
    # File lib/sequel/core.rb
468 def virtual_row(&block)
469   vr = VIRTUAL_ROW
470   case block.arity
471   when -1, 0
472     vr.instance_exec(&block)
473   else
474     yield(vr)
475   end  
476 end