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.
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 |
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 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
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
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
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
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
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
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
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
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
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
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
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 44 44: def add_index(table, columns, options={}) 45: e = options[:ignore_errors] 46: begin 47: alter_table(table){add_index(columns, options)} 48: rescue DatabaseError 49: raise unless e 50: end 51: 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 70 70: def alter_table(name, generator=nil, &block) 71: generator ||= Schema::AlterTableGenerator.new(self, &block) 72: alter_table_sql_list(name, generator.operations).flatten.each {|sql| execute_ddl(sql)} 73: remove_cached_schema(name) 74: nil 75: 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 115 115: def create_or_replace_view(name, source) 116: source = source.sql if source.is_a?(Dataset) 117: execute_ddl("CREATE OR REPLACE VIEW #{quote_schema_table(name)} AS #{source}") 118: remove_cached_schema(name) 119: nil 120: 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:
See Schema::Generator and the "Migrations and Schema Modification" guide.
# File lib/sequel/database/schema_methods.rb, line 91 91: def create_table(name, options={}, &block) 92: remove_cached_schema(name) 93: options = {:generator=>options} if options.is_a?(Schema::Generator) 94: generator = options[:generator] || Schema::Generator.new(self, &block) 95: create_table_from_generator(name, generator, options) 96: create_table_indexes_from_generator(name, generator, options) 97: nil 98: end
Forcibly creates a table, attempting to drop it unconditionally (and catching any errors), then creating it.
# File lib/sequel/database/schema_methods.rb, line 101 101: def create_table!(name, options={}, &block) 102: drop_table(name) rescue nil 103: create_table(name, options, &block) 104: end
Creates the table unless the table already exists
# File lib/sequel/database/schema_methods.rb, line 107 107: def create_table?(name, options={}, &block) 108: create_table(name, options, &block) unless table_exists?(name) 109: 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 126 126: def create_view(name, source) 127: source = source.sql if source.is_a?(Dataset) 128: execute_ddl("CREATE VIEW #{quote_schema_table(name)} AS #{source}") 129: end
Removes a column from the specified table:
DB.drop_column :items, :category
See alter_table.
# File lib/sequel/database/schema_methods.rb, line 136 136: def drop_column(table, *args) 137: alter_table(table) {drop_column(*args)} 138: 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 146 146: def drop_index(table, columns, options={}) 147: alter_table(table){drop_index(columns, options)} 148: end
Drops one or more views corresponding to the given names:
DB.drop_view(:cheap_items)
# File lib/sequel/database/schema_methods.rb, line 164 164: def drop_view(*names) 165: names.each do |n| 166: execute_ddl("DROP VIEW #{quote_schema_table(n)}") 167: remove_cached_schema(n) 168: end 169: nil 170: 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 189 189: def rename_column(table, *args) 190: alter_table(table) {rename_column(*args)} 191: 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 177 177: def rename_table(name, new_name) 178: execute_ddl(rename_table_sql(name, new_name)) 179: remove_cached_schema(name) 180: nil 181: 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 198 198: def set_column_default(table, *args) 199: alter_table(table) {set_column_default(*args)} 200: 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 207 207: def set_column_type(table, *args) 208: alter_table(table) {set_column_type(*args)} 209: end
These methods all return instances of this database‘s dataset class.
Returns a dataset from the database. If the first argument is a string, the method acts as an alias for Database#fetch, returning a dataset for arbitrary SQL:
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 18 18: def [](*args) 19: (String === args.first) ? fetch(*args) : from(*args) 20: 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 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 40 40: def fetch(sql, *args, &block) 41: ds = dataset.with_sql(sql, *args) 42: ds.each(&block) if block 43: ds 44: 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
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 |
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/ |
prepared_statements | [R] | The prepared statement objects for this database, keyed by name |
Call the prepared statement with the given name with the given hash of arguments.
# File lib/sequel/database/query.rb, line 35 35: def call(ps_name, hash={}) 36: prepared_statements[ps_name].call(hash) 37: 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 41 41: def execute(sql, opts={}) 42: raise NotImplemented, "#execute should be overridden by adapters" 43: end
Method that should be used when submitting any DDL (Data Definition Language) SQL. By default, calls execute_dui. This method should not be called directly by user code.
# File lib/sequel/database/query.rb, line 48 48: def execute_ddl(sql, opts={}, &block) 49: execute_dui(sql, opts, &block) 50: 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 62 62: def execute_insert(sql, opts={}, &block) 63: execute_dui(sql, opts, &block) 64: 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.
# File lib/sequel/database/query.rb, line 83 83: def indexes(table, opts={}) 84: raise NotImplemented, "#indexes should be overridden by adapters" 85: 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:
# File lib/sequel/database/query.rb, line 107 107: def schema(table, opts={}) 108: raise(Error, 'schema parsing is not implemented on this database') unless respond_to?(:schema_parse_table, true) 109: 110: sch, table_name = schema_and_table(table) 111: quoted_name = quote_schema_table(table) 112: opts = opts.merge(:schema=>sch) if sch && !opts.include?(:schema) 113: 114: @schemas.delete(quoted_name) if opts[:reload] 115: return @schemas[quoted_name] if @schemas[quoted_name] 116: 117: cols = schema_parse_table(table_name, opts) 118: raise(Error, 'schema parsing returned no columns, table probably doesn\'t exist') if cols.nil? || cols.empty? 119: cols.each{|_,c| c[:ruby_default] = column_schema_to_ruby_default(c[:default], c[:type])} 120: @schemas[quoted_name] = cols 121: 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:
# File lib/sequel/database/query.rb, line 150 150: def transaction(opts={}, &block) 151: synchronize(opts[:server]) do |conn| 152: return yield(conn) if already_in_transaction?(conn, opts) 153: _transaction(conn, &block) 154: end 155: 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
The method to call on identifiers coming from the database
# File lib/sequel/database/dataset_defaults.rb, line 68 68: def identifier_output_method 69: case @identifier_output_method 70: when nil 71: @identifier_output_method = @opts.fetch(:identifier_output_method, (@@identifier_output_method.nil? ? identifier_output_method_default : @@identifier_output_method)) 72: @identifier_output_method == "" ? nil : @identifier_output_method 73: when "" 74: nil 75: else 76: @identifier_output_method 77: end 78: end
Returns true if the database quotes identifiers.
# File lib/sequel/database/dataset_defaults.rb, line 93 93: def quote_identifiers? 94: return @quote_identifiers unless @quote_identifiers.nil? 95: @quote_identifiers = @opts.fetch(:quote_identifiers, (@@quote_identifiers.nil? ? quote_identifiers_default : @@quote_identifiers)) 96: end
This methods involve the Database‘s connection pool.
ADAPTERS | = | %w'ado amalgalite db2 dbi do firebird informix jdbc mysql odbc openbase oracle postgres sqlite'.collect{|x| x.to_sym} | Array of supported database adapters |
pool | [R] | The connection pool for this database |
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" 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: end 58: when Hash 59: opts = conn_string.merge(opts) 60: c = adapter_class(opts[:adapter] || opts['adapter']) 61: else 62: raise Error, "Sequel::Database.connect takes either a Hash or a String, given: #{conn_string.inspect}" 63: end 64: # process opts a bit 65: opts = opts.inject({}) do |m, kv| k, v = *kv 66: k = :user if k.to_s == 'username' 67: m[k.to_sym] = v 68: m 69: end 70: begin 71: db = c.new(opts) 72: db.test_connection if opts[:test] && db.send(:typecast_value_boolean, opts[:test]) 73: result = yield(db) if block_given? 74: ensure 75: if block_given? 76: db.disconnect if db 77: ::Sequel::DATABASES.delete(db) 78: end 79: end 80: block_given? ? result : db 81: 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 119 119: def add_servers(servers) 120: @opts[:servers] = @opts[:servers] ? @opts[:servers].merge(servers) : servers 121: @pool.add_servers(servers.keys) 122: end
Connects to the database. This method should be overridden by descendants.
# File lib/sequel/database/connecting.rb, line 125 125: def connect(server) 126: raise NotImplemented, "#connect should be overridden by adapters" 127: 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).
# File lib/sequel/database/connecting.rb, line 136 136: def database_type 137: self.class.adapter_scheme 138: end
Disconnects all available connections from the connection pool. Any connections currently in use will not be disconnected. Options:
# File lib/sequel/database/connecting.rb, line 144 144: def disconnect(opts = {}) 145: pool.disconnect(opts) 146: end
Yield a new database object 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 153 153: def each_server(&block) 154: servers.each{|s| self.class.connect(server_opts(s), &block)} 155: 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 167 167: def remove_servers(*servers) 168: if @opts[:servers] && !@opts[:servers].empty? 169: servs = @opts[:servers].dup 170: servers.flatten! 171: servers.each{|s| servs.delete(s)} 172: @opts[:servers] = servs 173: @pool.remove_servers(servers) 174: end 175: end
Returns true if the database is using a single-threaded connection pool.
# File lib/sequel/database/connecting.rb, line 183 183: def single_threaded? 184: @single_threaded 185: end
Acquires a database connection, yielding it to the passed block.
# File lib/sequel/database/connecting.rb, line 188 188: def synchronize(server=nil, &block) 189: @pool.hold(server || :default, &block) 190: end
These methods don‘t fit neatly into another category.
opts | [R] | The options for this database |
Constructs a new instance of a database connection with the specified options hash.
Sequel::Database is an abstract class that is not useful by itself.
Takes the following options:
All options given are also passed to the ConnectionPool. 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
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
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 68 68: def inspect 69: "#<#{self.class}: #{(uri rescue opts).inspect}>" 70: end
Default serial primary key options.
# File lib/sequel/database/misc.rb, line 78 78: def serial_primary_key_options 79: {:primary_key => true, :type => Integer, :auto_increment => true} 80: end
Whether the database and adapter support savepoints, false by default
# File lib/sequel/database/misc.rb, line 83 83: def supports_savepoints? 84: false 85: 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 92 92: def typecast_value(column_type, value) 93: return nil if value.nil? 94: meth = "typecast_value_#{column_type}" 95: begin 96: respond_to?(meth, true) ? send(meth, value) : value 97: rescue ArgumentError, TypeError => e 98: raise Sequel.convert_exception_class(e, InvalidValue) 99: end 100: end
Returns the URI identifying the database. This method can raise an error if the database used options instead of a connection string.
# File lib/sequel/database/misc.rb, line 105 105: def uri 106: uri = URI::Generic.new( 107: self.class.adapter_scheme.to_s, 108: nil, 109: @opts[:host], 110: @opts[:port], 111: nil, 112: "/#{@opts[:database]}", 113: nil, 114: nil, 115: nil 116: ) 117: uri.user = @opts[:user] 118: uri.password = @opts[:password] if uri.user 119: uri.to_s 120: end
These methods execute code on the database that modifies the database‘s schema.