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
SELECT_SERIAL_SEQUENCE | = | proc do |schema, table| <<-end_sql SELECT '"' || name.nspname || '".' || seq.relname || '' FROM pg_class seq, pg_attribute attr, pg_depend dep, pg_namespace name, pg_constraint cons WHERE seq.oid = dep.objid AND seq.relnamespace = name.oid AND seq.relkind = 'S' AND attr.attrelid = dep.refobjid AND attr.attnum = dep.refobjsubid AND attr.attrelid = cons.conrelid AND attr.attnum = cons.conkey[1] AND cons.contype = 'p' #{"AND name.nspname = '#{schema}'" if schema} AND seq.relname = '#{table}' end_sql | ||
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. | |
DEFAULT_INFLECTIONS_PROC | = | proc do plural(/$/, 's') | Proc that is instance evaled to create the default inflections for both the model inflector and the inflector extension. | |
LOCAL_DATETIME_OFFSET_SECS | = | Time.now.utc_offset | The offset of the current time zone from UTC, in seconds. | |
LOCAL_DATETIME_OFFSET | = | respond_to?(:Rational, true) ? Rational(LOCAL_DATETIME_OFFSET_SECS, 60*60*24) : LOCAL_DATETIME_OFFSET_SECS/60/60/24.0 | The offset of the current time zone from UTC, as a fraction of a day. | |
MAJOR | = | 3 | The major version of Sequel. Only bumped for major changes. | |
MINOR | = | 13 | The minor version of Sequel. Bumped for every non-patch level release, generally around once a month. | |
TINY | = | 0 | The tiny version of Sequel. Usually 0, only bumped for bugfix releases that fix regressions from previous versions. | |
VERSION | = | [MAJOR, MINOR, TINY].join('.') | The version of Sequel you are using, as a string (e.g. "2.11.0") |
convert_two_digit_years | [RW] |
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 |
datetime_class | [RW] |
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 |
virtual_row_instance_eval | [RW] | For backwards compatibility, has no effect. |
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. |
Symbol : | 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
# File lib/sequel/model.rb, line 37 37: def self.Model(source) 38: Model::ANONYMOUS_MODEL_CLASSES[source] ||= if source.is_a?(Database) 39: c = Class.new(Model) 40: c.db = source 41: c 42: else 43: Class.new(Model).set_dataset(source) 44: end 45: end
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
# File lib/sequel/core.rb, line 81 81: def self.condition_specifier?(obj) 82: case obj 83: when Hash 84: true 85: when Array 86: !obj.empty? && !obj.is_a?(SQL::ValueList) && obj.all?{|i| (Array === i) && (i.length == 2)} 87: else 88: false 89: end 90: end
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.
# File lib/sequel/core.rb, line 110 110: def self.connect(*args, &block) 111: Database.connect(*args, &block) 112: end
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.
# File lib/sequel/core.rb, line 117 117: def self.convert_exception_class(exception, klass) 118: return exception if exception.is_a?(klass) 119: e = klass.new("#{exception.class}: #{exception.message}") 120: e.wrapped_exception = exception 121: e.set_backtrace(exception.backtrace) 122: e 123: end
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)
# File lib/sequel/core.rb, line 135 135: def self.extension(*extensions) 136: extensions.each{|e| tsk_require "sequel/extensions/#{e}"} 137: end
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.
# File lib/sequel/core.rb, line 150 150: def self.identifier_input_method=(value) 151: Database.identifier_input_method = value 152: end
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.
# File lib/sequel/core.rb, line 166 166: def self.identifier_output_method=(value) 167: Database.identifier_output_method = value 168: end
Yield the Inflections module if a block is given, and return the Inflections module.
# File lib/sequel/model/inflections.rb, line 4 4: def self.inflections 5: yield Inflections if block_given? 6: Inflections 7: end
Allowing loading the necessary JDBC support via a gem, which works for PostgreSQL, MySQL, and SQLite.
# File lib/sequel/adapters/jdbc.rb, line 81 81: def self.load_gem(name) 82: begin 83: Sequel.tsk_require "jdbc/#{name}" 84: rescue LoadError 85: # jdbc gem not used, hopefully the user has the .jar in their CLASSPATH 86: end 87: end
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.
# File lib/sequel/extensions/migration.rb, line 124 124: def self.migration(&block) 125: MigrationDSL.create(&block) 126: end
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.
# File lib/sequel/core.rb, line 182 182: def self.require(files, subdir=nil) 183: Array(files).each{|f| super("#{File.dirname(__FILE__)}/#{"#{subdir}/" if subdir}#{f}")} 184: end
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
# File lib/sequel/core.rb, line 192 192: def self.single_threaded=(value) 193: Database.single_threaded = value 194: end
Converts the given string into a Date object.
Sequel.string_to_date('2010-09-10') # Date.civil(2010, 09, 10)
# File lib/sequel/core.rb, line 199 199: def self.string_to_date(string) 200: begin 201: Date.parse(string, Sequel.convert_two_digit_years) 202: rescue => e 203: raise convert_exception_class(e, InvalidValue) 204: end 205: end
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)
# File lib/sequel/core.rb, line 211 211: def self.string_to_datetime(string) 212: begin 213: if datetime_class == DateTime 214: DateTime.parse(string, convert_two_digit_years) 215: else 216: datetime_class.parse(string) 217: end 218: rescue => e 219: raise convert_exception_class(e, InvalidValue) 220: end 221: end
Converts the given string into a Time object.
Sequel.string_to_datetime('10:20:30') # Time.parse('10:20:30')
# File lib/sequel/core.rb, line 226 226: def self.string_to_time(string) 227: begin 228: Time.parse(string) 229: rescue => e 230: raise convert_exception_class(e, InvalidValue) 231: end 232: end
Same as Sequel.require, but wrapped in a mutex in order to be thread safe.
# File lib/sequel/core.rb, line 235 235: def self.ts_require(*args) 236: check_requiring_thread{require(*args)} 237: end
Same as Kernel.require, but wrapped in a mutex in order to be thread safe.
# File lib/sequel/core.rb, line 240 240: def self.tsk_require(*args) 241: check_requiring_thread{k_require(*args)} 242: end
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)
# File lib/sequel/core.rb, line 251 251: def self.virtual_row(&block) 252: vr = SQL::VirtualRow.new 253: case block.arity 254: when -1, 0 255: vr.instance_eval(&block) 256: else 257: block.call(vr) 258: end 259: end