A Database object represents a virtual connection to a database. The Database class is meant to be subclassed by database adapters in order to provide the functionality needed for executing queries.
Returns a dataset for the database. If the first argument is a string, the method acts as an alias for Database#fetch, returning a dataset for arbitrary SQL, with or without placeholders:
DB['SELECT * FROM items'].all DB['SELECT * FROM items WHERE name = ?', my_name].all
Otherwise, acts as an alias for Database#from, setting the primary table for the dataset:
DB[:items].sql #=> "SELECT * FROM items"
# File lib/sequel/database/dataset.rb, line 19
19: def [](*args)
20: (String === args.first) ? fetch(*args) : from(*args)
21: end
Fetches records for an arbitrary SQL statement. If a block is given, it is used to iterate over the records:
DB.fetch('SELECT * FROM items'){|r| p r}
The fetch method returns a dataset instance:
DB.fetch('SELECT * FROM items').all
fetch can also perform parameterized queries for protection against SQL injection:
DB.fetch('SELECT * FROM items WHERE name = ?', my_name).all
# File lib/sequel/database/dataset.rb, line 44
44: def fetch(sql, *args, &block)
45: ds = dataset.with_sql(sql, *args)
46: ds.each(&block) if block
47: ds
48: end
Returns a new dataset with the from method invoked. If a block is given, it is used as a filter on the dataset.
DB.from(:items) # SELECT * FROM items
DB.from(:items){id > 2} # SELECT * FROM items WHERE (id > 2)
# File lib/sequel/database/dataset.rb, line 55
55: def from(*args, &block)
56: ds = dataset.from(*args)
57: block ? ds.filter(&block) : ds
58: end
Returns a new dataset with the select method invoked.
DB.select(1) # SELECT 1
DB.select{server_version{}} # SELECT server_version()
DB.select(:id).from(:items) # SELECT id FROM items
# File lib/sequel/database/dataset.rb, line 65
65: def select(*args, &block)
66: dataset.select(*args, &block)
67: end
| AUTOINCREMENT | = | 'AUTOINCREMENT'.freeze |
| CASCADE | = | 'CASCADE'.freeze |
| COMMA_SEPARATOR | = | ', '.freeze |
| NO_ACTION | = | 'NO ACTION'.freeze |
| NOT_NULL | = | ' NOT NULL'.freeze |
| NULL | = | ' NULL'.freeze |
| PRIMARY_KEY | = | ' PRIMARY KEY'.freeze |
| RESTRICT | = | 'RESTRICT'.freeze |
| SET_DEFAULT | = | 'SET DEFAULT'.freeze |
| SET_NULL | = | 'SET NULL'.freeze |
| TEMPORARY | = | 'TEMPORARY '.freeze |
| UNDERSCORE | = | '_'.freeze |
| UNIQUE | = | ' UNIQUE'.freeze |
| UNSIGNED | = | ' UNSIGNED'.freeze |
Adds a column to the specified table. This method expects a column name, a datatype and optionally a hash with additional constraints and options:
DB.add_column :items, :name, :text, :unique => true, :null => false DB.add_column :items, :category, :text, :default => 'ruby'
See alter_table.
# File lib/sequel/database/schema_methods.rb, line 30
30: def add_column(table, *args)
31: alter_table(table) {add_column(*args)}
32: end
Adds an index to a table for the given columns:
DB.add_index :posts, :title DB.add_index :posts, [:author, :title], :unique => true
Options:
See alter_table.
# File lib/sequel/database/schema_methods.rb, line 43
43: def add_index(table, columns, options={})
44: e = options[:ignore_errors]
45: begin
46: alter_table(table){add_index(columns, options)}
47: rescue DatabaseError
48: raise unless e
49: end
50: end
Alters the given table with the specified block. Example:
DB.alter_table :items do
add_column :category, :text, :default => 'ruby'
drop_column :category
rename_column :cntr, :counter
set_column_type :value, :float
set_column_default :value, :float
add_index [:group, :category]
drop_index [:group, :category]
end
Note that add_column accepts all the options available for column definitions using create_table, and add_index accepts all the options available for index definition.
See Schema::AlterTableGenerator and the "Migrations and Schema Modification" guide.
# File lib/sequel/database/schema_methods.rb, line 69
69: def alter_table(name, generator=nil, &block)
70: generator ||= Schema::AlterTableGenerator.new(self, &block)
71: alter_table_sql_list(name, generator.operations).flatten.each {|sql| execute_ddl(sql)}
72: remove_cached_schema(name)
73: nil
74: end
Creates a view, replacing it if it already exists:
DB.create_or_replace_view(:cheap_items, "SELECT * FROM items WHERE price < 100") DB.create_or_replace_view(:ruby_items, DB[:items].filter(:category => 'ruby'))
# File lib/sequel/database/schema_methods.rb, line 118
118: def create_or_replace_view(name, source)
119: source = source.sql if source.is_a?(Dataset)
120: execute_ddl("CREATE OR REPLACE VIEW #{quote_schema_table(name)} AS #{source}")
121: remove_cached_schema(name)
122: nil
123: end
Creates a table with the columns given in the provided block:
DB.create_table :posts do
primary_key :id
column :title, :text
String :content
index :title
end
Options:
| :temp : | Create the table as a temporary table. |
| :ignore_index_errors : | Ignore any errors when creating indexes. |
See Schema::Generator and the "Migrations and Schema Modification" guide.
# File lib/sequel/database/schema_methods.rb, line 90
90: def create_table(name, options={}, &block)
91: remove_cached_schema(name)
92: options = {:generator=>options} if options.is_a?(Schema::Generator)
93: generator = options[:generator] || Schema::Generator.new(self, &block)
94: create_table_from_generator(name, generator, options)
95: create_table_indexes_from_generator(name, generator, options)
96: nil
97: end
Forcibly creates a table, attempting to drop it unconditionally (and catching any errors), then creating it.
DB.create_table!(:a){Integer :a}
# DROP TABLE a
# CREATE TABLE a (a integer)
# File lib/sequel/database/schema_methods.rb, line 104
104: def create_table!(name, options={}, &block)
105: drop_table(name) rescue nil
106: create_table(name, options, &block)
107: end
Creates the table unless the table already exists
# File lib/sequel/database/schema_methods.rb, line 110
110: def create_table?(name, options={}, &block)
111: create_table(name, options, &block) unless table_exists?(name)
112: end
Creates a view based on a dataset or an SQL string:
DB.create_view(:cheap_items, "SELECT * FROM items WHERE price < 100") DB.create_view(:ruby_items, DB[:items].filter(:category => 'ruby'))
# File lib/sequel/database/schema_methods.rb, line 129
129: def create_view(name, source)
130: source = source.sql if source.is_a?(Dataset)
131: execute_ddl("CREATE VIEW #{quote_schema_table(name)} AS #{source}")
132: end
Removes a column from the specified table:
DB.drop_column :items, :category
See alter_table.
# File lib/sequel/database/schema_methods.rb, line 139
139: def drop_column(table, *args)
140: alter_table(table) {drop_column(*args)}
141: end
Removes an index for the given table and column/s:
DB.drop_index :posts, :title DB.drop_index :posts, [:author, :title]
See alter_table.
# File lib/sequel/database/schema_methods.rb, line 149
149: def drop_index(table, columns, options={})
150: alter_table(table){drop_index(columns, options)}
151: end
Drops one or more views corresponding to the given names:
DB.drop_view(:cheap_items)
# File lib/sequel/database/schema_methods.rb, line 167
167: def drop_view(*names)
168: names.each do |n|
169: execute_ddl("DROP VIEW #{quote_schema_table(n)}")
170: remove_cached_schema(n)
171: end
172: nil
173: end
Renames a column in the specified table. This method expects the current column name and the new column name:
DB.rename_column :items, :cntr, :counter
See alter_table.
# File lib/sequel/database/schema_methods.rb, line 192
192: def rename_column(table, *args)
193: alter_table(table) {rename_column(*args)}
194: end
Renames a table:
DB.tables #=> [:items] DB.rename_table :items, :old_items DB.tables #=> [:old_items]
# File lib/sequel/database/schema_methods.rb, line 180
180: def rename_table(name, new_name)
181: execute_ddl(rename_table_sql(name, new_name))
182: remove_cached_schema(name)
183: nil
184: end
Sets the default value for the given column in the given table:
DB.set_column_default :items, :category, 'perl!'
See alter_table.
# File lib/sequel/database/schema_methods.rb, line 201
201: def set_column_default(table, *args)
202: alter_table(table) {set_column_default(*args)}
203: end
Set the data type for the given column in the given table:
DB.set_column_type :items, :price, :float
See alter_table.
# File lib/sequel/database/schema_methods.rb, line 210
210: def set_column_type(table, *args)
211: alter_table(table) {set_column_type(*args)}
212: end
This methods affect relating to the logging of executed SQL.
Log a message at level info to all loggers.
# File lib/sequel/database/logging.rb, line 16
16: def log_info(message, args=nil)
17: log_each(:info, args ? "#{message}; #{args.inspect}" : message)
18: end
Yield to the block, logging any errors at error level to all loggers, and all other queries with the duration at warn or info level.
# File lib/sequel/database/logging.rb, line 22
22: def log_yield(sql, args=nil)
23: return yield if @loggers.empty?
24: sql = "#{sql}; #{args.inspect}" if args
25: start = Time.now
26: begin
27: yield
28: rescue => e
29: log_each(:error, "#{e.class}: #{e.message.strip}: #{sql}")
30: raise
31: ensure
32: log_duration(Time.now - start, sql) unless e
33: end
34: end
This methods involve the Database‘s connection pool.
| ADAPTERS | = | %w'ado amalgalite db2 dbi do firebird informix jdbc mysql mysql2 odbc openbase oracle postgres sqlite swift'.collect{|x| x.to_sym} | Array of supported database adapters |
The Database subclass for the given adapter scheme. Raises Sequel::AdapterNotFound if the adapter could not be loaded.
# File lib/sequel/database/connecting.rb, line 17
17: def self.adapter_class(scheme)
18: scheme = scheme.to_s.gsub('-', '_').to_sym
19:
20: unless klass = ADAPTER_MAP[scheme]
21: # attempt to load the adapter file
22: begin
23: Sequel.tsk_require "sequel/adapters/#{scheme}"
24: rescue LoadError => e
25: raise Sequel.convert_exception_class(e, AdapterNotFound)
26: end
27:
28: # make sure we actually loaded the adapter
29: unless klass = ADAPTER_MAP[scheme]
30: raise AdapterNotFound, "Could not load #{scheme} adapter: adapter class not registered in ADAPTER_MAP"
31: end
32: end
33: klass
34: end
Connects to a database. See Sequel.connect.
# File lib/sequel/database/connecting.rb, line 42
42: def self.connect(conn_string, opts = {})
43: case conn_string
44: when String
45: if match = /\A(jdbc|do):/o.match(conn_string)
46: c = adapter_class(match[1].to_sym)
47: opts = {:uri=>conn_string}.merge(opts)
48: else
49: uri = URI.parse(conn_string)
50: scheme = uri.scheme
51: scheme = :dbi if scheme =~ /\Adbi-/
52: c = adapter_class(scheme)
53: uri_options = c.send(:uri_to_options, uri)
54: uri.query.split('&').collect{|s| s.split('=')}.each{|k,v| uri_options[k.to_sym] = v if k && !k.empty?} unless uri.query.to_s.strip.empty?
55: uri_options.entries.each{|k,v| uri_options[k] = URI.unescape(v) if v.is_a?(String)}
56: opts = uri_options.merge(opts)
57: opts[:adapter] = scheme
58: end
59: when Hash
60: opts = conn_string.merge(opts)
61: c = adapter_class(opts[:adapter] || opts['adapter'])
62: else
63: raise Error, "Sequel::Database.connect takes either a Hash or a String, given: #{conn_string.inspect}"
64: end
65: # process opts a bit
66: opts = opts.inject({}) do |m, (k,v)|
67: k = :user if k.to_s == 'username'
68: m[k.to_sym] = v
69: m
70: end
71: begin
72: db = c.new(opts)
73: db.test_connection if opts[:test] && db.send(:typecast_value_boolean, opts[:test])
74: result = yield(db) if block_given?
75: ensure
76: if block_given?
77: db.disconnect if db
78: ::Sequel::DATABASES.delete(db)
79: end
80: end
81: block_given? ? result : db
82: end
Returns the scheme symbol for this instance‘s class, which reflects which adapter is being used. In some cases, this can be the same as the database_type (for native adapters), in others (i.e. adapters with subadapters), it will be different.
Sequel.connect('jdbc:postgres://...').adapter_scheme # => :jdbc
# File lib/sequel/database/connecting.rb, line 118
118: def adapter_scheme
119: self.class.adapter_scheme
120: end
Dynamically add new servers or modify server options at runtime. Also adds new servers to the connection pool. Intended for use with master/slave or shard configurations where it is useful to add new server hosts at runtime.
servers argument should be a hash with server name symbol keys and hash or proc values. If a servers key is already in use, it‘s value is overridden with the value provided.
DB.add_servers(:f=>{:host=>"hash_host_f"})
# File lib/sequel/database/connecting.rb, line 131
131: def add_servers(servers)
132: @opts[:servers] = @opts[:servers] ? @opts[:servers].merge(servers) : servers
133: @pool.add_servers(servers.keys)
134: end
Connects to the database. This method should be overridden by descendants.
# File lib/sequel/database/connecting.rb, line 137
137: def connect(server)
138: raise NotImplemented, "#connect should be overridden by adapters"
139: end
The database type for this database object, the same as the adapter scheme by default. Should be overridden in adapters (especially shared adapters) to be the correct type, so that even if two separate Database objects are using different adapters you can tell that they are using the same database type. Even better, you can tell that two Database objects that are using the same adapter are connecting to different database types (think JDBC or DataObjects).
Sequel.connect('jdbc:postgres://...').database_type # => :postgres
# File lib/sequel/database/connecting.rb, line 150
150: def database_type
151: adapter_scheme
152: end
Disconnects all available connections from the connection pool. Any connections currently in use will not be disconnected. Options:
Example:
DB.disconnect # All servers DB.disconnect(:servers=>:server1) # Single server DB.disconnect(:servers=>[:server1, :server2]) # Multiple servers
# File lib/sequel/database/connecting.rb, line 164
164: def disconnect(opts = {})
165: pool.disconnect(opts)
166: end
Yield a new Database instance for every server in the connection pool. Intended for use in sharded environments where there is a need to make schema modifications (DDL queries) on each shard.
DB.each_server{|db| db.create_table(:users){primary_key :id; String :name}}
# File lib/sequel/database/connecting.rb, line 173
173: def each_server(&block)
174: servers.each{|s| self.class.connect(server_opts(s), &block)}
175: end
Dynamically remove existing servers from the connection pool. Intended for use with master/slave or shard configurations where it is useful to remove existing server hosts at runtime.
servers should be symbols or arrays of symbols. If a nonexistent server is specified, it is ignored. If no servers have been specified for this database, no changes are made. If you attempt to remove the :default server, an error will be raised.
DB.remove_servers(:f1, :f2)
# File lib/sequel/database/connecting.rb, line 187
187: def remove_servers(*servers)
188: if @opts[:servers] && !@opts[:servers].empty?
189: servs = @opts[:servers].dup
190: servers.flatten!
191: servers.each{|s| servs.delete(s)}
192: @opts[:servers] = servs
193: @pool.remove_servers(servers)
194: end
195: end
Returns true if the database is using a single-threaded connection pool.
# File lib/sequel/database/connecting.rb, line 206
206: def single_threaded?
207: @single_threaded
208: end
Acquires a database connection, yielding it to the passed block. This is useful if you want to make sure the same connection is used for all database queries in the block. It is also useful if you want to gain direct access to the underlying connection object if you need to do something Sequel does not natively support.
If a server option is given, acquires a connection for that specific server, instead of the :default server.
DB.synchronize do |conn|
...
end
# File lib/sequel/database/connecting.rb, line 223
223: def synchronize(server=nil, &block)
224: @pool.hold(server || :default, &block)
225: end
Attempts to acquire a database connection. Returns true if successful. Will probably raise an Error if unsuccessful. If a server argument is given, attempts to acquire a database connection to the given server/shard.
# File lib/sequel/database/connecting.rb, line 231
231: def test_connection(server=nil)
232: synchronize(server){|conn|}
233: true
234: end
These methods don‘t fit neatly into another category.
| opts | [R] | The options hash for this database |
Constructs a new instance of a database connection with the specified options hash.
Accepts the following options:
| :default_schema : | The default schema to use, should generally be nil |
| :disconnection_proc : | A proc used to disconnect the connection |
| :identifier_input_method : | A string method symbol to call on identifiers going into the database |
| :identifier_output_method : | A string method symbol to call on identifiers coming from the database |
| :logger : | A specific logger to use |
| :loggers : | An array of loggers to use |
| :quote_identifiers : | Whether to quote identifiers |
| :servers : | A hash specifying a server/shard specific options, keyed by shard symbol |
| :single_threaded : | Whether to use a single-threaded connection pool |
All options given are also passed to the connection pool. If a block is given, it is used as the connection_proc for the ConnectionPool.
# File lib/sequel/database/misc.rb, line 38
38: def initialize(opts = {}, &block)
39: @opts ||= opts
40: @opts = connection_pool_default_options.merge(@opts)
41: @loggers = Array(@opts[:logger]) + Array(@opts[:loggers])
42: self.log_warn_duration = @opts[:log_warn_duration]
43: @opts[:disconnection_proc] ||= proc{|conn| disconnect_connection(conn)}
44: block ||= proc{|server| connect(server)}
45: @opts[:servers] = {} if @opts[:servers].is_a?(String)
46:
47: @opts[:single_threaded] = @single_threaded = typecast_value_boolean(@opts.fetch(:single_threaded, @@single_threaded))
48: @schemas = {}
49: @default_schema = @opts.fetch(:default_schema, default_schema_default)
50: @prepared_statements = {}
51: @transactions = []
52: @identifier_input_method = nil
53: @identifier_output_method = nil
54: @quote_identifiers = nil
55: @pool = ConnectionPool.get_pool(@opts, &block)
56:
57: ::Sequel::DATABASES.push(self)
58: end
Returns a string representation of the database object including the class name and the connection URI (or the opts if the URI cannot be constructed).
# File lib/sequel/database/misc.rb, line 71
71: def inspect
72: "#<#{self.class}: #{(uri rescue opts).inspect}>"
73: end
Default serial primary key options, used by the table creation code.
# File lib/sequel/database/misc.rb, line 86
86: def serial_primary_key_options
87: {:primary_key => true, :type => Integer, :auto_increment => true}
88: end
Whether the database and adapter support prepared transactions (two-phase commit), false by default.
# File lib/sequel/database/misc.rb, line 92
92: def supports_prepared_transactions?
93: false
94: end
Whether the database and adapter support savepoints, false by default.
# File lib/sequel/database/misc.rb, line 97
97: def supports_savepoints?
98: false
99: end
Whether the database and adapter support transaction isolation levels, false by default.
# File lib/sequel/database/misc.rb, line 102
102: def supports_transaction_isolation_levels?
103: false
104: end
Typecast the value to the given column_type. Calls typecast_value_#{column_type} if the method exists, otherwise returns the value. This method should raise Sequel::InvalidValue if assigned value is invalid.
# File lib/sequel/database/misc.rb, line 111
111: def typecast_value(column_type, value)
112: return nil if value.nil?
113: meth = "typecast_value_#{column_type}"
114: begin
115: respond_to?(meth, true) ? send(meth, value) : value
116: rescue ArgumentError, TypeError => e
117: raise Sequel.convert_exception_class(e, InvalidValue)
118: end
119: end
Returns the URI identifying the database, which may not be the same as the URI used when connecting. This method can raise an error if the database used options instead of a connection string, and will not include uri parameters.
Sequel.connect('postgres://localhost/db?user=billg').url
# => "postgres://billg@localhost/db"
# File lib/sequel/database/misc.rb, line 129
129: def uri
130: uri = URI::Generic.new(
131: adapter_scheme.to_s,
132: nil,
133: @opts[:host],
134: @opts[:port],
135: nil,
136: "/#{@opts[:database]}",
137: nil,
138: nil,
139: nil
140: )
141: uri.user = @opts[:user]
142: uri.password = @opts[:password] if uri.user
143: uri.to_s
144: end
This methods change the default behavior of this database‘s datasets.
| default_schema | [RW] | The default schema to use, generally should be nil. |
The method to call on identifiers going into the database
# File lib/sequel/database/dataset_defaults.rb, line 49
49: def identifier_input_method
50: case @identifier_input_method
51: when nil
52: @identifier_input_method = @opts.fetch(:identifier_input_method, (@@identifier_input_method.nil? ? identifier_input_method_default : @@identifier_input_method))
53: @identifier_input_method == "" ? nil : @identifier_input_method
54: when ""
55: nil
56: else
57: @identifier_input_method
58: end
59: end
Set the method to call on identifiers going into the database:
DB[:items] # SELECT * FROM items DB.identifier_input_method = :upcase DB[:items] # SELECT * FROM ITEMS
# File lib/sequel/database/dataset_defaults.rb, line 66
66: def identifier_input_method=(v)
67: reset_schema_utility_dataset
68: @identifier_input_method = v || ""
69: end
The method to call on identifiers coming from the database
# File lib/sequel/database/dataset_defaults.rb, line 72
72: def identifier_output_method
73: case @identifier_output_method
74: when nil
75: @identifier_output_method = @opts.fetch(:identifier_output_method, (@@identifier_output_method.nil? ? identifier_output_method_default : @@identifier_output_method))
76: @identifier_output_method == "" ? nil : @identifier_output_method
77: when ""
78: nil
79: else
80: @identifier_output_method
81: end
82: end
Set the method to call on identifiers coming from the database:
DB[:items].first # {:id=>1, :name=>'foo'}
DB.identifier_output_method = :upcase
DB[:items].first # {:ID=>1, :NAME=>'foo'}
# File lib/sequel/database/dataset_defaults.rb, line 89
89: def identifier_output_method=(v)
90: reset_schema_utility_dataset
91: @identifier_output_method = v || ""
92: end
Set whether to quote identifiers (columns and tables) for this database:
DB[:items] # SELECT * FROM items DB.quote_identifiers = true DB[:items] # SELECT * FROM "items"
# File lib/sequel/database/dataset_defaults.rb, line 99
99: def quote_identifiers=(v)
100: reset_schema_utility_dataset
101: @quote_identifiers = v
102: end
Returns true if the database quotes identifiers.
# File lib/sequel/database/dataset_defaults.rb, line 105
105: def quote_identifiers?
106: return @quote_identifiers unless @quote_identifiers.nil?
107: @quote_identifiers = @opts.fetch(:quote_identifiers, (@@quote_identifiers.nil? ? quote_identifiers_default : @@quote_identifiers))
108: end
| SQL_BEGIN | = | 'BEGIN'.freeze |
| SQL_COMMIT | = | 'COMMIT'.freeze |
| SQL_RELEASE_SAVEPOINT | = | 'RELEASE SAVEPOINT autopoint_%d'.freeze |
| SQL_ROLLBACK | = | 'ROLLBACK'.freeze |
| SQL_ROLLBACK_TO_SAVEPOINT | = | 'ROLLBACK TO SAVEPOINT autopoint_%d'.freeze |
| SQL_SAVEPOINT | = | 'SAVEPOINT autopoint_%d'.freeze |
| TRANSACTION_BEGIN | = | 'Transaction.begin'.freeze |
| TRANSACTION_COMMIT | = | 'Transaction.commit'.freeze |
| TRANSACTION_ROLLBACK | = | 'Transaction.rollback'.freeze |
| TRANSACTION_ISOLATION_LEVELS | = | {:uncommitted=>'READ UNCOMMITTED'.freeze, :committed=>'READ COMMITTED'.freeze, :repeatable=>'REPEATABLE READ'.freeze, :serializable=>'SERIALIZABLE'.freeze} |
| POSTGRES_DEFAULT_RE | = | /\A(?:B?('.*')::[^']+|\((-?\d+(?:\.\d+)?)\))\z/ |
| MSSQL_DEFAULT_RE | = | /\A(?:\(N?('.*')\)|\(\((-?\d+(?:\.\d+)?)\)\))\z/ |
| MYSQL_TIMESTAMP_RE | = | /\ACURRENT_(?:DATE|TIMESTAMP)?\z/ |
| STRING_DEFAULT_RE | = | /\A'(.*)'\z/ |
| convert_types | [RW] | Whether to convert some Java types to ruby types when retrieving rows. True by default, can be set to false to roughly double performance when fetching rows. |
| database_type | [R] | The type of database we are connecting to |
| driver | [R] | The Java database driver we are using |
| prepared_statements | [R] | The prepared statement object hash for this database, keyed by name symbol |
| swift_class | [RW] | The Swift adapter class being used by this database. Connections in this database‘s connection pool will be instances of this class. |
| transaction_isolation_level | [RW] | The default transaction isolation level for this database, used for all future transactions. For MSSQL, this should be set to something if you ever plan to use the :isolation option to Database#transaction, as on MSSQL if affects all future transactions on the same connection. |
Call the DATABASE_SETUP proc directly after initialization, so the object always uses sub adapter specific code. Also, raise an error immediately if the connection doesn‘t have a uri, since JDBC requires one.
# File lib/sequel/adapters/jdbc.rb, line 109
109: def initialize(opts)
110: super
111: @convert_types = typecast_value_boolean(@opts.fetch(:convert_types, true))
112: raise(Error, "No connection string specified") unless uri
113:
114: resolved_uri = jndi? ? get_uri_from_jndi : uri
115:
116: if match = /\Ajdbc:([^:]+)/.match(resolved_uri) and prok = DATABASE_SETUP[match[1].to_sym]
117: @driver = prok.call(self)
118: end
119: end
Call the DATABASE_SETUP proc directly after initialization, so the object always uses sub adapter specific code. Also, raise an error immediately if the connection doesn‘t have a db_type specified, since one is required to include the correct subadapter.
# File lib/sequel/adapters/swift.rb, line 39
39: def initialize(opts)
40: super
41: if db_type = opts[:db_type] and !db_type.to_s.empty?
42: if prok = DATABASE_SETUP[db_type.to_s.to_sym]
43: prok.call(self)
44: else
45: raise(Error, "No :db_type option specified")
46: end
47: else
48: raise(Error, ":db_type option not valid, should be postgres or mysql")
49: end
50: end
Call the DATABASE_SETUP proc directly after initialization, so the object always uses sub adapter specific code. Also, raise an error immediately if the connection doesn‘t have a uri, since DataObjects requires one.
# File lib/sequel/adapters/do.rb, line 45
45: def initialize(opts)
46: super
47: raise(Error, "No connection string specified") unless uri
48: if prok = DATABASE_SETUP[subadapter.to_sym]
49: prok.call(self)
50: end
51: end
Call the prepared statement with the given name with the given hash of arguments.
DB[:items].filter(:id=>1).prepare(:first, :sa) DB.call(:sa) # SELECT * FROM items WHERE id = 1
# File lib/sequel/database/query.rb, line 50
50: def call(ps_name, hash={})
51: prepared_statements[ps_name].call(hash)
52: end
Execute the given stored procedure with the give name. If a block is given, the stored procedure should return rows.
# File lib/sequel/adapters/jdbc.rb, line 123
123: def call_sproc(name, opts = {})
124: args = opts[:args] || []
125: sql = "{call #{name}(#{args.map{'?'}.join(',')})}"
126: synchronize(opts[:server]) do |conn|
127: cps = conn.prepareCall(sql)
128:
129: i = 0
130: args.each{|arg| set_ps_arg(cps, arg, i+=1)}
131:
132: begin
133: if block_given?
134: yield log_yield(sql){cps.executeQuery}
135: else
136: case opts[:type]
137: when :insert
138: log_yield(sql){cps.executeUpdate}
139: last_insert_id(conn, opts)
140: else
141: log_yield(sql){cps.executeUpdate}
142: end
143: end
144: rescue NativeException, JavaSQL::SQLException => e
145: raise_error(e)
146: ensure
147: cps.close
148: end
149: end
150: end
Create an instance of swift_class for the given options.
# File lib/sequel/adapters/swift.rb, line 53
53: def connect(server)
54: setup_connection(swift_class.new(server_opts(server)))
55: end
Setup a DataObjects::Connection to the database.
# File lib/sequel/adapters/do.rb, line 54
54: def connect(server)
55: setup_connection(::DataObjects::Connection.new(uri(server_opts(server))))
56: end
Connect to the database using JavaSQL::DriverManager.getConnection.
# File lib/sequel/adapters/jdbc.rb, line 153
153: def connect(server)
154: opts = server_opts(server)
155: conn = if jndi?
156: get_connection_from_jndi
157: else
158: args = [uri(opts)]
159: args.concat([opts[:user], opts[:password]]) if opts[:user] && opts[:password]
160: begin
161: JavaSQL::DriverManager.getConnection(*args)
162: rescue => e
163: raise e unless driver
164: # If the DriverManager can't get the connection - use the connect
165: # method of the driver. (This happens under Tomcat for instance)
166: props = java.util.Properties.new
167: if opts && opts[:user] && opts[:password]
168: props.setProperty("user", opts[:user])
169: props.setProperty("password", opts[:password])
170: end
171: driver.new.connect(args[0], props) rescue (raise e)
172: end
173: end
174: setup_connection(conn)
175: end
Return a Sequel::Swift::Dataset object for this database.
# File lib/sequel/adapters/swift.rb, line 58
58: def dataset(opts = nil)
59: Swift::Dataset.new(self, opts)
60: end
Return a Sequel::DataObjects::Dataset object for this database.
# File lib/sequel/adapters/do.rb, line 59
59: def dataset(opts = nil)
60: DataObjects::Dataset.new(self, opts)
61: end
Return instances of JDBC::Dataset with the given opts.
# File lib/sequel/adapters/jdbc.rb, line 178
178: def dataset(opts = nil)
179: JDBC::Dataset.new(self, opts)
180: end
Dump indexes for all tables as a migration. This complements the :indexes=>false option to dump_schema_migration. Options:
# File lib/sequel/extensions/schema_dumper.rb, line 13
13: def dump_indexes_migration(options={})
14: ts = tables(options)
15: "Sequel.migration do\n up do\n\#{ts.sort_by{|t| t.to_s}.map{|t| dump_table_indexes(t, :add_index, options)}.reject{|x| x == ''}.join(\"\\n\\n\").gsub(/^/o, ' ')}\n end\n \n down do\n\#{ts.sort_by{|t| t.to_s}.map{|t| dump_table_indexes(t, :drop_index, options)}.reject{|x| x == ''}.join(\"\\n\\n\").gsub(/^/o, ' ')}\n end\nend\n"
16: end
Return a string that contains a Sequel::Migration subclass that when run would recreate the database structure. Options:
# File lib/sequel/extensions/schema_dumper.rb, line 38
38: def dump_schema_migration(options={})
39: ts = tables(options)
40: "Sequel.migration do\n up do\n\#{ts.sort_by{|t| t.to_s}.map{|t| dump_table_schema(t, options)}.join(\"\\n\\n\").gsub(/^/o, ' ')}\n end\n \n down do\n drop_table(\#{ts.sort_by{|t| t.to_s}.inspect[1...-1]})\n end\nend\n"
41: end
Return a string with a create table block that will recreate the given table‘s schema. Takes the same options as dump_schema_migration.
# File lib/sequel/extensions/schema_dumper.rb, line 56
56: def dump_table_schema(table, options={})
57: table = table.value.to_s if table.is_a?(SQL::Identifier)
58: raise(Error, "must provide table as a Symbol, String, or Sequel::SQL::Identifier") unless [String, Symbol].any?{|c| table.is_a?(c)}
59: s = schema(table).dup
60: pks = s.find_all{|x| x.last[:primary_key] == true}.map{|x| x.first}
61: options = options.merge(:single_pk=>true) if pks.length == 1
62: m = method(:column_schema_to_generator_opts)
63: im = method(:index_to_generator_opts)
64: begin
65: indexes = indexes(table).sort_by{|k,v| k.to_s} if options[:indexes] != false
66: rescue Sequel::NotImplemented
67: nil
68: end
69: gen = Schema::Generator.new(self) do
70: s.each{|name, info| send(*m.call(name, info, options))}
71: primary_key(pks) if !@primary_key && pks.length > 0
72: indexes.each{|iname, iopts| send(:index, iopts[:columns], im.call(table, iname, iopts))} if indexes
73: end
74: commands = [gen.dump_columns, gen.dump_constraints, gen.dump_indexes].reject{|x| x == ''}.join("\n\n")
75: "create_table(#{table.inspect}#{', :ignore_index_errors=>true' if !options[:same_db] && options[:indexes] != false && indexes && !indexes.empty?}) do\n#{commands.gsub(/^/o, ' ')}\nend"
76: end
Execute the given SQL, yielding a Swift::Result if a block is given.
# File lib/sequel/adapters/swift.rb, line 63
63: def execute(sql, opts={})
64: synchronize(opts[:server]) do |conn|
65: begin
66: res = nil
67: log_yield(sql){res = conn.prepare(sql).execute}
68: yield res if block_given?
69: nil
70: rescue SwiftError => e
71: raise_error(e)
72: ensure
73: res.finish if res
74: end
75: end
76: end
Execute the given SQL. If a block is given, the DataObjects::Reader created is yielded to it. A block should not be provided unless a a SELECT statement is being used (or something else that returns rows). Otherwise, the return value is the insert id if opts[:type] is :insert, or the number of affected rows, otherwise.
# File lib/sequel/adapters/do.rb, line 68
68: def execute(sql, opts={})
69: synchronize(opts[:server]) do |conn|
70: begin
71: command = conn.create_command(sql)
72: res = log_yield(sql){block_given? ? command.execute_reader : command.execute_non_query}
73: rescue ::DataObjects::Error => e
74: raise_error(e)
75: end
76: if block_given?
77: begin
78: yield(res)
79: ensure
80: res.close if res
81: end
82: elsif opts[:type] == :insert
83: res.insert_id
84: else
85: res.affected_rows
86: end
87: end
88: end
Execute the given SQL. If a block is given, if should be a SELECT statement or something else that returns rows.
# File lib/sequel/adapters/jdbc.rb, line 184
184: def execute(sql, opts={}, &block)
185: return call_sproc(sql, opts, &block) if opts[:sproc]
186: return execute_prepared_statement(sql, opts, &block) if [Symbol, Dataset].any?{|c| sql.is_a?(c)}
187: synchronize(opts[:server]) do |conn|
188: statement(conn) do |stmt|
189: if block_given?
190: yield log_yield(sql){stmt.executeQuery(sql)}
191: else
192: case opts[:type]
193: when :ddl
194: log_yield(sql){stmt.execute(sql)}
195: when :insert
196: log_yield(sql) do
197: if requires_return_generated_keys?
198: stmt.executeUpdate(sql, JavaSQL::Statement.RETURN_GENERATED_KEYS)
199: else
200: stmt.executeUpdate(sql)
201: end
202: end
203: last_insert_id(conn, opts.merge(:stmt=>stmt))
204: else
205: log_yield(sql){stmt.executeUpdate(sql)}
206: end
207: end
208: end
209: end
210: end
Executes the given SQL on the database. This method should be overridden in descendants. This method should not be called directly by user code.
# File lib/sequel/database/query.rb, line 56
56: def execute(sql, opts={})
57: raise NotImplemented, "#execute should be overridden by adapters"
58: end
Method that should be used when submitting any DDL (Data Definition Language) SQL, such as create_table. By default, calls execute_dui. This method should not be called directly by user code.
# File lib/sequel/database/query.rb, line 63
63: def execute_ddl(sql, opts={}, &block)
64: execute_dui(sql, opts, &block)
65: end
Execute the SQL on the this database, returning the number of affected rows.
# File lib/sequel/adapters/swift.rb, line 80
80: def execute_dui(sql, opts={})
81: synchronize(opts[:server]) do |conn|
82: begin
83: log_yield(sql){conn.execute(sql)}
84: rescue SwiftError => e
85: raise_error(e)
86: end
87: end
88: end
Method that should be used when issuing a INSERT statement. By default, calls execute_dui. This method should not be called directly by user code.
# File lib/sequel/database/query.rb, line 77
77: def execute_insert(sql, opts={}, &block)
78: execute_dui(sql, opts, &block)
79: end
Execute the SQL on this database, returning the primary key of the table being inserted to.
# File lib/sequel/adapters/swift.rb, line 92
92: def execute_insert(sql, opts={})
93: synchronize(opts[:server]) do |conn|
94: begin
95: log_yield(sql){conn.prepare(sql).execute.insert_id}
96: rescue SwiftError => e
97: raise_error(e)
98: end
99: end
100: end
Use the JDBC metadata to get the index information for the table.
# File lib/sequel/adapters/jdbc.rb, line 226
226: def indexes(table, opts={})
227: m = output_identifier_meth
228: im = input_identifier_meth
229: schema, table = schema_and_table(table)
230: schema ||= opts[:schema]
231: schema = im.call(schema) if schema
232: table = im.call(table)
233: indexes = {}
234: metadata(:getIndexInfo, nil, schema, table, false, true) do |r|
235: next unless name = r[:column_name]
236: next if respond_to?(:primary_key_index_re, true) and r[:index_name] =~ primary_key_index_re
237: i = indexes[m.call(r[:index_name])] ||= {:columns=>[], :unique=>[false, 0].include?(r[:non_unique])}
238: i[:columns] << m.call(name)
239: end
240: indexes
241: end
Return a hash containing index information. Hash keys are index name symbols. Values are subhashes with two keys, :columns and :unique. The value of :columns is an array of symbols of column names. The value of :unique is true or false depending on if the index is unique.
Should not include the primary key index, functional indexes, or partial indexes.
DB.indexes(:artists)
# => {:artists_name_ukey=>{:columns=>[:name], :unique=>true}}
# File lib/sequel/database/query.rb, line 99
99: def indexes(table, opts={})
100: raise NotImplemented, "#indexes should be overridden by adapters"
101: end
Whether or not JNDI is being used for this connection.
# File lib/sequel/adapters/jdbc.rb, line 262
262: def jndi?
263: !!(uri =~ JNDI_URI_REGEXP)
264: end
Parse the schema from the database. Returns the schema for the given table as an array with all members being arrays of length 2, the first member being the column name, and the second member being a hash of column information. Available options are:
| :reload : | Ignore any cached results, and get fresh information from the database. |
| :schema : | An explicit schema to use. It may also be implicitly provided via the table name. |
If schema parsing is supported by the database, the column information should at least contain the following columns:
| :allow_null : | Whether NULL is an allowed value for the column. |
| :db_type : | The database type for the column, as a database specific string. |
| :default : | The database default for the column, as a database specific string. |
| :primary_key : | Whether the columns is a primary key column. If this column is not present, it means that primary key information is unavailable, not that the column is not a primary key. |
| :ruby_default : | The database default for the column, as a ruby object. In many cases, complex database defaults cannot be parsed into ruby objects. |
| :type : | A symbol specifying the type, such as :integer or :string. |
Example:
DB.schema(:artists)
# [[:id,
# {:type=>:integer,
# :primary_key=>true,
# :default=>"nextval('artist_id_seq'::regclass)",
# :ruby_default=>nil,
# :db_type=>"integer",
# :allow_null=>false}],
# [:name,
# {:type=>:string,
# :primary_key=>false,
# :default=>nil,
# :ruby_default=>nil,
# :db_type=>"text",
# :allow_null=>false}]]
# File lib/sequel/database/query.rb, line 152
152: def schema(table, opts={})
153: raise(Error, 'schema parsing is not implemented on this database') unless respond_to?(:schema_parse_table, true)
154:
155: sch, table_name = schema_and_table(table)
156: quoted_name = quote_schema_table(table)
157: opts = opts.merge(:schema=>sch) if sch && !opts.include?(:schema)
158:
159: @schemas.delete(quoted_name) if opts[:reload]
160: return @schemas[quoted_name] if @schemas[quoted_name]
161:
162: cols = schema_parse_table(table_name, opts)
163: raise(Error, 'schema parsing returned no columns, table probably doesn\'t exist') if cols.nil? || cols.empty?
164: cols.each{|_,c| c[:ruby_default] = column_schema_to_ruby_default(c[:default], c[:type])}
165: @schemas[quoted_name] = cols
166: end
Return the subadapter type for this database, i.e. sqlite3 for do:sqlite3::memory:.
# File lib/sequel/adapters/do.rb, line 104
104: def subadapter
105: uri.split(":").first
106: end
Starts a database transaction. When a database transaction is used, either all statements are successful or none of the statements are successful. Note that MySQL MyISAM tabels do not support transactions.
The following options are respected:
| :isolation : | The transaction isolation level to use for this transaction, should be :uncommitted, :committed, :repeatable, or :serializable, used if given and the database/adapter supports customizable transaction isolation levels. |
| :prepare : | A string to use as the transaction identifier for a prepared transaction (two-phase commit), if the database/adapter supports prepared transactions. |
| :server : | The server to use for the transaction. |
| :savepoint : | Whether to create a new savepoint for this transaction, only respected if the database/adapter supports savepoints. By default Sequel will reuse an existing transaction, so if you want to use a savepoint you must use this option. |
# File lib/sequel/database/query.rb, line 206
206: def transaction(opts={}, &block)
207: synchronize(opts[:server]) do |conn|
208: return yield(conn) if already_in_transaction?(conn, opts)
209: _transaction(conn, opts, &block)
210: end
211: end
Return the DataObjects URI for the Sequel URI, removing the do: prefix.
# File lib/sequel/adapters/do.rb, line 110
110: def uri(opts={})
111: opts = @opts.merge(opts)
112: (opts[:uri] || opts[:url]).sub(/\Ado:/, '')
113: end
The uri for this connection. You can specify the uri using the :uri, :url, or :database options. You don‘t need to worry about this if you use Sequel.connect with the JDBC connectrion strings.
# File lib/sequel/adapters/jdbc.rb, line 255
255: def uri(opts={})
256: opts = @opts.merge(opts)
257: ur = opts[:uri] || opts[:url] || opts[:database]
258: ur =~ /^\Ajdbc:/ ? ur : "jdbc:#{ur}"
259: end
These methods all return instances of this database‘s dataset class.