frozen-string-literal: true
ADAPTER_MAP | = | {} | Hash of adapters that have been used. The key is the adapter scheme symbol, and the value is the Database subclass. | |
SHARED_ADAPTER_MAP | = | {} | Hash of shared adapters that have been registered. The key is the adapter scheme symbol, and the value is the Sequel module containing the shared adapter. | |
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 use the :keep_reference Database option or a block when connecting) or they will not get garbage collected. | |
MYSQL_TYPES | = | {} | Hash with integer keys and callable values for converting MySQL types. | |
CONVERSION_PROCS | = | {} | ||
VIRTUAL_ROW | = | new | ||
OPTS | = | {}.freeze | Frozen hash used as the default options hash for most options. | |
SPLIT_SYMBOL_CACHE | = | {} | ||
AdapterNotFound | = | Class.new(Error) | Error raised when the adapter requested doesn‘t exist or can‘t be loaded. | |
DatabaseError | = | Class.new(Error) | Generic error raised by the database adapters, indicating a problem originating from the database server. Usually raised because incorrect SQL syntax is used. | |
DatabaseConnectionError | = | Class.new(DatabaseError) | Error raised when the Sequel is unable to connect to the database with the connection parameters it was given. | |
DatabaseDisconnectError | = | Class.new(DatabaseError) | Error raised by adapters when they determine that the connection to the database has been lost. Instructs the connection pool code to remove that connection from the pool so that other connections can be acquired automatically. | |
ConstraintViolation | = | Class.new(DatabaseError) | Generic error raised when Sequel determines a database constraint has been violated. | |
CheckConstraintViolation | = | Class.new(ConstraintViolation) | Error raised when Sequel determines a database check constraint has been violated. | |
ForeignKeyConstraintViolation | = | Class.new(ConstraintViolation) | Error raised when Sequel determines a database foreign key constraint has been violated. | |
NotNullConstraintViolation | = | Class.new(ConstraintViolation) | Error raised when Sequel determines a database NOT NULL constraint has been violated. | |
UniqueConstraintViolation | = | Class.new(ConstraintViolation) | Error raised when Sequel determines a database unique constraint has been violated. | |
SerializationFailure | = | Class.new(DatabaseError) | Error raised when Sequel determines a serialization failure/deadlock in the database. | |
DatabaseLockTimeout | = | Class.new(DatabaseError) | Error raised when Sequel determines the database could not acquire a necessary lock before timing out. Use of Dataset#nowait can often cause this exception when retrieving rows. | |
InvalidOperation | = | Class.new(Error) | Error raised on an invalid operation, such as trying to update or delete a joined or grouped dataset when the database does not support that. | |
InvalidValue | = | Class.new(Error) | Error raised when attempting an invalid type conversion. | |
PoolTimeout | = | Class.new(Error) | Error raised when the connection pool cannot acquire a database connection before the timeout. | |
Rollback | = | Class.new(Error) | Error that you should raise to signal a rollback of the current transaction. The transaction block will catch this exception, rollback the current transaction, and won‘t reraise it (unless a reraise is requested). | |
MAJOR | = | 5 | The major version of Sequel. Only bumped for major changes. | |
MINOR | = | 9 | 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('.').freeze | The version of Sequel you are using, as a string (e.g. "2.11.0") | |
VERSION_NUMBER | = | MAJOR*10000 + MINOR*10 + TINY | The version of Sequel you are using, as a number (2.11.0 -> 20110) | |
DEFAULT_INFLECTIONS_PROC | = | proc do plural(/$/, 's') | Proc that is instance_execed to create the default inflections for both the model inflector and the inflector extension. | |
NoExistingObject | = | Class.new(Error) | Exception class raised when require_modification is set and an UPDATE or DELETE statement to modify the dataset doesn‘t modify a single row. | |
UndefinedAssociation | = | Class.new(Error) | Raised when an undefined association is used when eager loading. | |
MassAssignmentRestriction | = | Class.new(Error) | Raised when a mass assignment method is called in strict mode with either a restricted column or a column without a setter method. |
expr | -> | [] |
Allow nicer syntax for creating Sequel
expressions:
Sequel[1] # => Sequel::SQL::NumericExpression: 1 Sequel["a"] # => Sequel::SQL::StringExpression: 'a' Sequel[:a] # => Sequel::SQL::Identifier: "a" Sequel[a: 1] # => Sequel::SQL::BooleanExpression: ("a" = 1) |
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 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). |
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 |
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 72 72: def self.condition_specifier?(obj) 73: case obj 74: when Hash 75: true 76: when Array 77: !obj.empty? && !obj.is_a?(SQL::ValueList) && obj.all?{|i| i.is_a?(Array) && (i.length == 2)} 78: else 79: false 80: end 81: 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)
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 master/slave or sharded database connection, see the "Master/Slave Databases and Sharding" guide.
# File lib/sequel/core.rb, line 115 115: def self.connect(*args, &block) 116: Database.connect(*args, &block) 117: 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 128 128: def self.convert_exception_class(exception, klass) 129: return exception if exception.is_a?(klass) 130: e = klass.new("#{exception.class}: #{exception.message}") 131: e.wrapped_exception = exception 132: e.set_backtrace(exception.backtrace) 133: e 134: end
The elapsed seconds since the given timer object was created. The timer object should have been created via Sequel.start_timer.
# File lib/sequel/core.rb, line 322 322: def self.elapsed_seconds_since(timer) 323: start_timer - timer 324: end
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)
# File lib/sequel/core.rb, line 144 144: def self.extension(*extensions) 145: extensions.each{|e| Kernel.require "sequel/extensions/#{e}"} 146: end
Yield the Inflections module if a block is given, and return the Inflections module.
# File lib/sequel/model/inflections.rb, line 6 6: def self.inflections 7: yield Inflections if block_given? 8: Inflections 9: end
The exception classed raised if there is an error parsing JSON. This can be overridden to use an alternative json implementation.
# File lib/sequel/core.rb, line 150 150: def self.json_parser_error_class 151: JSON::ParserError 152: 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 288 288: def self.migration(&block) 289: MigrationDSL.create(&block) 290: end
# File lib/sequel/adapters/shared/postgres.rb, line 84 84: def self.mock_adapter_setup(db) 85: db.instance_exec do 86: @server_version = 90500 87: initialize_postgres_adapter 88: extend(MockAdapterDatabaseMethods) 89: end 90: end
Convert given object to json and return the result. This can be overridden to use an alternative json implementation.
# File lib/sequel/core.rb, line 156 156: def self.object_to_json(obj, *args, &block) 157: obj.to_json(*args, &block) 158: end
Parse the string as JSON and return the result. This can be overridden to use an alternative json implementation.
# File lib/sequel/core.rb, line 162 162: def self.parse_json(json) 163: JSON.parse(json, :create_additions=>false) 164: end
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.
# File lib/sequel/core.rb, line 169 169: def self.recursive_map(array, converter) 170: array.map do |i| 171: if i.is_a?(Array) 172: recursive_map(i, converter) 173: elsif !i.nil? 174: converter.call(i) 175: end 176: end 177: end
For backwards compatibility only. require_relative should be used instead.
# File lib/sequel/core.rb, line 180 180: def self.require(files, subdir=nil) 181: # Use Kernel.require_relative to work around JRuby 9.0 bug 182: Array(files).each{|f| Kernel.require_relative "#{"#{subdir}/" if subdir}#{f}"} 183: end
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 beind 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.
# File lib/sequel/core.rb, line 194 194: def self.split_symbol(sym) 195: unless v = Sequel.synchronize{SPLIT_SYMBOL_CACHE[sym]} 196: if split_symbols? 197: v = case s = sym.to_s 198: when /\A((?:(?!__).)+)__((?:(?!___).)+)___(.+)\z/ 199: [$1.freeze, $2.freeze, $3.freeze].freeze 200: when /\A((?:(?!___).)+)___(.+)\z/ 201: [nil, $1.freeze, $2.freeze].freeze 202: when /\A((?:(?!__).)+)__(.+)\z/ 203: [$1.freeze, $2.freeze, nil].freeze 204: else 205: [nil, s.freeze, nil].freeze 206: end 207: else 208: v = [nil,sym.to_s.freeze,nil].freeze 209: end 210: Sequel.synchronize{SPLIT_SYMBOL_CACHE[sym] = v} 211: end 212: v 213: end
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 identifers 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
# File lib/sequel/core.rb, line 245 245: def self.split_symbols=(v) 246: Sequel.synchronize{SPLIT_SYMBOL_CACHE.clear} 247: @split_symbols = v 248: end
A timer object that can be passed to Sequel.elapsed_seconds_since to return the number of seconds elapsed.
# File lib/sequel/core.rb, line 309 309: def self.start_timer 310: Process.clock_gettime(Process::CLOCK_MONOTONIC) 311: 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 258 258: def self.string_to_date(string) 259: begin 260: Date.parse(string, Sequel.convert_two_digit_years) 261: rescue => e 262: raise convert_exception_class(e, InvalidValue) 263: end 264: 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 270 270: def self.string_to_datetime(string) 271: begin 272: if datetime_class == DateTime 273: DateTime.parse(string, convert_two_digit_years) 274: else 275: datetime_class.parse(string) 276: end 277: rescue => e 278: raise convert_exception_class(e, InvalidValue) 279: end 280: end
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'
# File lib/sequel/core.rb, line 286 286: def self.string_to_time(string) 287: begin 288: SQLTime.parse(string) 289: rescue => e 290: raise convert_exception_class(e, InvalidValue) 291: end 292: end
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.
# File lib/sequel/core.rb, line 302 302: def self.synchronize(&block) 303: @single_threaded ? yield : @data_mutex.synchronize(&block) 304: end
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).
# File lib/sequel/core.rb, line 348 348: def self.transaction(dbs, opts=OPTS, &block) 349: unless opts[:rollback] 350: rescue_rollback = true 351: opts = Hash[opts].merge!(:rollback=>:reraise) 352: end 353: pr = dbs.reverse.inject(block){|bl, db| proc{db.transaction(opts, &bl)}} 354: if rescue_rollback 355: begin 356: pr.call 357: rescue Sequel::Rollback 358: nil 359: end 360: else 361: pr.call 362: end 363: end
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)
# File lib/sequel/core.rb, line 372 372: def self.virtual_row(&block) 373: vr = VIRTUAL_ROW 374: case block.arity 375: when -1, 0 376: vr.instance_exec(&block) 377: else 378: block.call(vr) 379: end 380: end
# File lib/sequel/adapters/jdbc.rb, line 725 725: def fetch_rows(sql, &block) 726: execute(sql){|result| process_result_set(result, &block)} 727: self 728: end
Set whether to convert Java types to ruby types in the returned dataset.
# File lib/sequel/adapters/jdbc.rb, line 736 736: def with_convert_types(v) 737: clone(:convert_types=>v) 738: end