# File lib/sequel/adapters/shared/postgres.rb, line 372 def primary_key(table, opts={}) quoted_table = quote_schema_table(table) Sequel.synchronize{return @primary_keys[quoted_table] if @primary_keys.has_key?(quoted_table)} sql = "#{SELECT_PK_SQL} AND pg_class.oid = #{literal(regclass_oid(table, opts))}" value = fetch(sql).single_value Sequel.synchronize{@primary_keys[quoted_table] = value} end
module Sequel::Postgres::DatabaseMethods
Methods shared by Database instances that connect to PostgreSQL.
Constants
- DATABASE_ERROR_REGEXPS
- EXCLUDE_SCHEMAS
- EXCLUSION_CONSTRAINT_SQL_STATE
- FOREIGN_KEY_LIST_ON_DELETE_MAP
- POSTGRES_DEFAULT_RE
- PREPARED_ARG_PLACEHOLDER
- RE_CURRVAL_ERROR
- SELECT_CUSTOM_SEQUENCE_SQL
SQL fragment for custom sequences (ones not created by serial primary key), Returning the schema and literal form of the sequence name, by parsing the column defaults table.
- SELECT_PK_SQL
SQL fragment for determining primary key column for the given table. Only returns the first primary key if the table has a composite primary key.
- SELECT_SERIAL_SEQUENCE_SQL
SQL fragment for getting sequence associated with table's primary key, assuming it was a serial primary key column.
- SYSTEM_TABLE_REGEXP
- UNLOGGED
- VALID_CLIENT_MIN_MESSAGES
Attributes
A hash of conversion procs, keyed by type integer (oid) and having callable values for the conversion proc for that type.
Public Instance Methods
Commit an existing prepared transaction with the given transaction identifier string.
# File lib/sequel/adapters/shared/postgres.rb, line 158 def commit_prepared_transaction(transaction_id) run("COMMIT PREPARED #{literal(transaction_id)}") end
Creates the function in the database. Arguments:
-
name : name of the function to create
-
definition : string definition of the function, or object file for a dynamically loaded C function.
-
opts : options hash:
-
:args : function arguments, can be either a symbol or string specifying a type or an array of 1-3 elements:
-
element 1 : argument data type
-
element 2 : argument name
-
element 3 : argument mode (e.g. in, out, inout)
-
-
:behavior : Should be IMMUTABLE, STABLE, or VOLATILE. PostgreSQL assumes VOLATILE by default.
-
:cost : The estimated cost of the function, used by the query planner.
-
:language : The language the function uses. SQL is the default.
-
:link_symbol : For a dynamically loaded see function, the function's link symbol if different from the definition argument.
-
:returns : The data type returned by the function. If you are using OUT or INOUT argument modes, this is ignored. Otherwise, if this is not specified, void is used by default to specify the function is not supposed to return a value.
-
:rows : The estimated number of rows the function will return. Only use if the function returns SETOF something.
-
:security_definer : Makes the privileges of the function the same as the privileges of the user who defined the function instead of the privileges of the user who runs the function. There are security implications when doing this, see the PostgreSQL documentation.
-
:set : Configuration variables to set while the function is being run, can be a hash or an array of two pairs. search_path is often used here if :security_definer is used.
-
:strict : Makes the function return NULL when any argument is NULL.
-
# File lib/sequel/adapters/shared/postgres.rb, line 182 def create_function(name, definition, opts={}) self << create_function_sql(name, definition, opts) end
Create the procedural language in the database. Arguments:
-
name : Name of the procedural language (e.g. plpgsql)
-
opts : options hash:
-
:handler : The name of a previously registered function used as a call handler for this language.
-
:replace: Replace the installed language if it already exists (on PostgreSQL 9.0+).
-
:trusted : Marks the language being created as trusted, allowing unprivileged users to create functions using this language.
-
:validator : The name of previously registered function used as a validator of functions defined in this language.
-
# File lib/sequel/adapters/shared/postgres.rb, line 193 def create_language(name, opts={}) self << create_language_sql(name, opts) end
Create a schema in the database. Arguments:
-
name : Name of the schema (e.g. admin)
# File lib/sequel/adapters/shared/postgres.rb, line 199 def create_schema(name) self << create_schema_sql(name) end
Create a trigger in the database. Arguments:
-
table : the table on which this trigger operates
-
name : the name of this trigger
-
function : the function to call for this trigger, which should return type trigger.
-
opts : options hash:
-
:after : Calls the trigger after execution instead of before.
-
:args : An argument or array of arguments to pass to the function.
-
:each_row : Calls the trigger for each row instead of for each statement.
-
:events : Can be :insert, :update, :delete, or an array of any of those. Calls the trigger whenever that type of statement is used. By default, the trigger is called for insert, update, or delete.
-
# File lib/sequel/adapters/shared/postgres.rb, line 213 def create_trigger(table, name, function, opts={}) self << create_trigger_sql(table, name, function, opts) end
PostgreSQL uses the :postgres database type.
# File lib/sequel/adapters/shared/postgres.rb, line 218 def database_type :postgres end
Use PostgreSQL's DO syntax to execute an anonymous code block. The code should be the literal code string to use in the underlying procedural language. Options:
- :language
-
The procedural language the code is written in. The PostgreSQL default is plpgsql. Can be specified as a string or a symbol.
# File lib/sequel/adapters/shared/postgres.rb, line 227 def do(code, opts={}) language = opts[:language] run "DO #{"LANGUAGE #{literal(language.to_s)} " if language}#{literal(code)}" end
Drops the function from the database. Arguments:
-
name : name of the function to drop
-
opts : options hash:
-
:args : The arguments for the function. See create_function_sql.
-
:cascade : Drop other objects depending on this function.
-
:if_exists : Don't raise an error if the function doesn't exist.
-
# File lib/sequel/adapters/shared/postgres.rb, line 238 def drop_function(name, opts={}) self << drop_function_sql(name, opts) end
Drops a procedural language from the database. Arguments:
-
name : name of the procedural language to drop
-
opts : options hash:
-
:cascade : Drop other objects depending on this function.
-
:if_exists : Don't raise an error if the function doesn't exist.
-
# File lib/sequel/adapters/shared/postgres.rb, line 247 def drop_language(name, opts={}) self << drop_language_sql(name, opts) end
Drops a schema from the database. Arguments:
-
name : name of the schema to drop
-
opts : options hash:
-
:cascade : Drop all objects in this schema.
-
:if_exists : Don't raise an error if the schema doesn't exist.
-
# File lib/sequel/adapters/shared/postgres.rb, line 256 def drop_schema(name, opts={}) self << drop_schema_sql(name, opts) end
Drops a trigger from the database. Arguments:
-
table : table from which to drop the trigger
-
name : name of the trigger to drop
-
opts : options hash:
-
:cascade : Drop other objects depending on this function.
-
:if_exists : Don't raise an error if the function doesn't exist.
-
# File lib/sequel/adapters/shared/postgres.rb, line 266 def drop_trigger(table, name, opts={}) self << drop_trigger_sql(table, name, opts) end
Return full foreign key information using the pg system tables, including :name, :on_delete, :on_update, and :deferrable entries in the hashes.
# File lib/sequel/adapters/shared/postgres.rb, line 272 def foreign_key_list(table, opts={}) m = output_identifier_meth schema, _ = opts.fetch(:schema, schema_and_table(table)) range = 0...32 base_ds = metadata_dataset. from(:pg_constraint___co). join(:pg_class___cl, :oid=>:conrelid). where(:cl__relkind=>'r', :co__contype=>'f', :cl__oid=>regclass_oid(table)) # We split the parsing into two separate queries, which are merged manually later. # This is because PostgreSQL stores both the referencing and referenced columns in # arrays, and I don't know a simple way to not create a cross product, as PostgreSQL # doesn't appear to have a function that takes an array and element and gives you # the index of that element in the array. ds = base_ds. join(:pg_attribute___att, :attrelid=>:oid, :attnum=>SQL::Function.new(:ANY, :co__conkey)). order(:co__conname, SQL::CaseExpression.new(range.map{|x| [SQL::Subscript.new(:co__conkey, [x]), x]}, 32, :att__attnum)). select(:co__conname___name, :att__attname___column, :co__confupdtype___on_update, :co__confdeltype___on_delete, SQL::BooleanExpression.new(:AND, :co__condeferrable, :co__condeferred).as(:deferrable)) ref_ds = base_ds. join(:pg_class___cl2, :oid=>:co__confrelid). join(:pg_attribute___att2, :attrelid=>:oid, :attnum=>SQL::Function.new(:ANY, :co__confkey)). order(:co__conname, SQL::CaseExpression.new(range.map{|x| [SQL::Subscript.new(:co__conkey, [x]), x]}, 32, :att2__attnum)). select(:co__conname___name, :cl2__relname___table, :att2__attname___refcolumn) # If a schema is given, we only search in that schema, and the returned :table # entry is schema qualified as well. if schema ref_ds = ref_ds.join(:pg_namespace___nsp2, :oid=>:cl2__relnamespace). select_more(:nsp2__nspname___schema) end h = {} fklod_map = FOREIGN_KEY_LIST_ON_DELETE_MAP ds.each do |row| if r = h[row[:name]] r[:columns] << m.call(row[:column]) else h[row[:name]] = {:name=>m.call(row[:name]), :columns=>[m.call(row[:column])], :on_update=>fklod_map[row[:on_update]], :on_delete=>fklod_map[row[:on_delete]], :deferrable=>row[:deferrable]} end end ref_ds.each do |row| r = h[row[:name]] r[:table] ||= schema ? SQL::QualifiedIdentifier.new(m.call(row[:schema]), m.call(row[:table])) : m.call(row[:table]) r[:key] ||= [] r[:key] << m.call(row[:refcolumn]) end h.values end
Use the pg_* system tables to determine indexes on a table
# File lib/sequel/adapters/shared/postgres.rb, line 326 def indexes(table, opts={}) m = output_identifier_meth range = 0...32 attnums = server_version >= 80100 ? SQL::Function.new(:ANY, :ind__indkey) : range.map{|x| SQL::Subscript.new(:ind__indkey, [x])} ds = metadata_dataset. from(:pg_class___tab). join(:pg_index___ind, :indrelid=>:oid). join(:pg_class___indc, :oid=>:indexrelid). join(:pg_attribute___att, :attrelid=>:tab__oid, :attnum=>attnums). left_join(:pg_constraint___con, :conname=>:indc__relname). filter(:indc__relkind=>'i', :ind__indisprimary=>false, :indexprs=>nil, :indpred=>nil, :indisvalid=>true, :tab__oid=>regclass_oid(table, opts)). order(:indc__relname, SQL::CaseExpression.new(range.map{|x| [SQL::Subscript.new(:ind__indkey, [x]), x]}, 32, :att__attnum)). select(:indc__relname___name, :ind__indisunique___unique, :att__attname___column, :con__condeferrable___deferrable) ds.filter!(:indisready=>true, :indcheckxmin=>false) if server_version >= 80300 indexes = {} ds.each do |r| i = indexes[m.call(r[:name])] ||= {:columns=>[], :unique=>r[:unique], :deferrable=>r[:deferrable]} i[:columns] << m.call(r[:column]) end indexes end
Dataset containing all current database locks
# File lib/sequel/adapters/shared/postgres.rb, line 351 def locks dataset.from(:pg_class).join(:pg_locks, :relation=>:relfilenode).select(:pg_class__relname, Sequel::SQL::ColumnAll.new(:pg_locks)) end
Notifies the given channel. See the PostgreSQL NOTIFY documentation. Options:
- :payload
-
The payload string to use for the NOTIFY statement. Only supported in PostgreSQL 9.0+.
- :server
-
The server to which to send the NOTIFY statement, if the sharding support is being used.
# File lib/sequel/adapters/shared/postgres.rb, line 361 def notify(channel, opts={}) sql = "NOTIFY " dataset.send(:identifier_append, sql, channel) if payload = opts[:payload] sql << ", " dataset.literal_append(sql, payload.to_s) end execute_ddl(sql, opts) end
Return primary key for the given table.
Return the sequence providing the default for the primary key for the given table.
# File lib/sequel/adapters/shared/postgres.rb, line 381 def primary_key_sequence(table, opts={}) quoted_table = quote_schema_table(table) Sequel.synchronize{return @primary_key_sequences[quoted_table] if @primary_key_sequences.has_key?(quoted_table)} sql = "#{SELECT_SERIAL_SEQUENCE_SQL} AND t.oid = #{literal(regclass_oid(table, opts))}" if pks = fetch(sql).single_record value = literal(SQL::QualifiedIdentifier.new(pks[:schema], pks[:sequence])) Sequel.synchronize{@primary_key_sequences[quoted_table] = value} else sql = "#{SELECT_CUSTOM_SEQUENCE_SQL} AND t.oid = #{literal(regclass_oid(table, opts))}" if pks = fetch(sql).single_record value = literal(SQL::QualifiedIdentifier.new(pks[:schema], LiteralString.new(pks[:sequence]))) Sequel.synchronize{@primary_key_sequences[quoted_table] = value} end end end
Reset the database's conversion procs, requires a server query if there any named types.
# File lib/sequel/adapters/shared/postgres.rb, line 399 def reset_conversion_procs @conversion_procs = get_conversion_procs end
Reset the primary key sequence for the given table, basing it on the maximum current value of the table's primary key.
# File lib/sequel/adapters/shared/postgres.rb, line 405 def reset_primary_key_sequence(table) return unless seq = primary_key_sequence(table) pk = SQL::Identifier.new(primary_key(table)) db = self seq_ds = db.from(LiteralString.new(seq)) s, t = schema_and_table(table) table = Sequel.qualify(s, t) if s get{setval(seq, db[table].select{coalesce(max(pk)+seq_ds.select{:increment_by}, seq_ds.select(:min_value))}, false)} end
Rollback an existing prepared transaction with the given transaction identifier string.
# File lib/sequel/adapters/shared/postgres.rb, line 417 def rollback_prepared_transaction(transaction_id) run("ROLLBACK PREPARED #{literal(transaction_id)}") end
PostgreSQL uses SERIAL psuedo-type instead of AUTOINCREMENT for managing incrementing primary keys.
# File lib/sequel/adapters/shared/postgres.rb, line 423 def serial_primary_key_options {:primary_key => true, :serial => true, :type=>Integer} end
The version of the PostgreSQL server, used for determining capability.
# File lib/sequel/adapters/shared/postgres.rb, line 428 def server_version(server=nil) return @server_version if @server_version @server_version = synchronize(server) do |conn| (conn.server_version rescue nil) if conn.respond_to?(:server_version) end unless @server_version @server_version = if m = /PostgreSQL (\d+)\.(\d+)(?:(?:rc\d+)|\.(\d+))?/.match(fetch('SELECT version()').single_value) (m[1].to_i * 10000) + (m[2].to_i * 100) + m[3].to_i else 0 end end warn 'Sequel no longer supports PostgreSQL <8.2, some things may not work' if @server_version < 80200 @server_version end
PostgreSQL supports CREATE TABLE IF NOT EXISTS on 9.1+
# File lib/sequel/adapters/shared/postgres.rb, line 445 def supports_create_table_if_not_exists? server_version >= 90100 end
PostgreSQL 9.0+ supports some types of deferrable constraints beyond foreign key constraints.
# File lib/sequel/adapters/shared/postgres.rb, line 450 def supports_deferrable_constraints? server_version >= 90000 end
PostgreSQL supports deferrable foreign key constraints.
# File lib/sequel/adapters/shared/postgres.rb, line 455 def supports_deferrable_foreign_key_constraints? true end
PostgreSQL supports DROP TABLE IF EXISTS
# File lib/sequel/adapters/shared/postgres.rb, line 460 def supports_drop_table_if_exists? true end
PostgreSQL supports prepared transactions (two-phase commit) if max_prepared_transactions is greater than 0.
# File lib/sequel/adapters/shared/postgres.rb, line 466 def supports_prepared_transactions? return @supports_prepared_transactions if defined?(@supports_prepared_transactions) @supports_prepared_transactions = self['SHOW max_prepared_transactions'].get.to_i > 0 end
PostgreSQL supports savepoints
# File lib/sequel/adapters/shared/postgres.rb, line 472 def supports_savepoints? true end
PostgreSQL supports transaction isolation levels
# File lib/sequel/adapters/shared/postgres.rb, line 477 def supports_transaction_isolation_levels? true end
PostgreSQL supports transaction DDL statements.
# File lib/sequel/adapters/shared/postgres.rb, line 482 def supports_transactional_ddl? true end
Array of symbols specifying table names in the current database. The dataset used is yielded to the block if one is provided, otherwise, an array of symbols of table names is returned.
Options:
- :qualify
-
Return the tables as Sequel::SQL::QualifiedIdentifier instances, using the schema the table is located in as the qualifier.
- :schema
-
The schema to search
- :server
-
The server to use
# File lib/sequel/adapters/shared/postgres.rb, line 495 def tables(opts={}, &block) pg_class_relname('r', opts, &block) end
Check whether the given type name string/symbol (e.g. :hstore) is supported by the database.
# File lib/sequel/adapters/shared/postgres.rb, line 501 def type_supported?(type) @supported_types ||= {} @supported_types.fetch(type){@supported_types[type] = (from(:pg_type).filter(:typtype=>'b', :typname=>type.to_s).count > 0)} end
Array of symbols specifying view names in the current database.
Options:
- :qualify
-
Return the views as Sequel::SQL::QualifiedIdentifier instances, using the schema the view is located in as the qualifier.
- :schema
-
The schema to search
- :server
-
The server to use
# File lib/sequel/adapters/shared/postgres.rb, line 513 def views(opts={}) pg_class_relname('v', opts) end
Private Instance Methods
Do a type name-to-oid lookup using the database and update the procs with the related proc if the database supports the type.
# File lib/sequel/adapters/shared/postgres.rb, line 521 def add_named_conversion_procs(procs, named_procs) unless (named_procs).empty? convert_named_procs_to_procs(named_procs).each do |oid, pr| procs[oid] ||= pr end end end
Use a PostgreSQL-specific alter table generator
# File lib/sequel/adapters/shared/postgres.rb, line 530 def alter_table_generator_class Postgres::AlterTableGenerator end
Handle :using option for set_column_type op, and the :validate_constraint op.
# File lib/sequel/adapters/shared/postgres.rb, line 535 def alter_table_op_sql(table, op) case op[:op] when :set_column_type s = super if using = op[:using] using = Sequel::LiteralString.new(using) if using.is_a?(String) s << ' USING ' s << literal(using) end s when :validate_constraint "VALIDATE CONSTRAINT #{quote_identifier(op[:name])}" else super end end
If the :synchronous option is given and non-nil, set synchronous_commit appropriately. Valid values for the :synchronous option are true, :on, false, :off, :local, and :remote_write.
# File lib/sequel/adapters/shared/postgres.rb, line 555 def begin_new_transaction(conn, opts) super if opts.has_key?(:synchronous) case sync = opts[:synchronous] when true sync = :on when false sync = :off when nil return end log_connection_execute(conn, "SET LOCAL synchronous_commit = #{sync}") end end
Handle PostgreSQL specific default format.
# File lib/sequel/adapters/shared/postgres.rb, line 572 def column_schema_normalize_default(default, type) if m = POSTGRES_DEFAULT_RE.match(default) default = m[1] || m[2] end super(default, type) end
PostgreSQL can't combine rename_column operations, and it can combine the custom validate_constraint operation.
# File lib/sequel/adapters/shared/postgres.rb, line 591 def combinable_alter_table_op?(op) (super || op[:op] == :validate_constraint) && op[:op] != :rename_column end
If the :prepare option is given and we aren't in a savepoint, prepare the transaction for a two-phase commit.
# File lib/sequel/adapters/shared/postgres.rb, line 581 def commit_transaction(conn, opts={}) if (s = opts[:prepare]) && _trans(conn)[:savepoint_level] <= 1 log_connection_execute(conn, "PREPARE TRANSACTION #{literal(s)}") else super end end
The SQL queries to execute when starting a new connection.
# File lib/sequel/adapters/shared/postgres.rb, line 597 def connection_configuration_sqls sqls = [] sqls << "SET standard_conforming_strings = ON" if typecast_value_boolean(@opts.fetch(:force_standard_strings, Postgres.force_standard_strings)) if (cmm = @opts.fetch(:client_min_messages, Postgres.client_min_messages)) && !cmm.to_s.empty? cmm = cmm.to_s.upcase.strip unless VALID_CLIENT_MIN_MESSAGES.include?(cmm) Sequel::Deprecation.deprecate("Using an unsupported client_min_messages setting will raise an Error in Sequel 4.") end sqls << "SET client_min_messages = '#{cmm.to_s.upcase}'" end if search_path = @opts[:search_path] case search_path when String search_path = search_path.split(",").map{|s| s.strip} when Array # nil else raise Error, "unrecognized value for :search_path option: #{search_path.inspect}" end sqls << "SET search_path = #{search_path.map{|s| "\"#{s.gsub('"', '""')}\""}.join(',')}" end sqls end
Handle exclusion constraints.
# File lib/sequel/adapters/shared/postgres.rb, line 626 def constraint_definition_sql(constraint) case constraint[:type] when :exclude elements = constraint[:elements].map{|c, op| "#{literal(c)} WITH #{op}"}.join(', ') "#{"CONSTRAINT #{quote_identifier(constraint[:name])} " if constraint[:name]}EXCLUDE USING #{constraint[:using]||'gist'} (#{elements})#{" WHERE #{filter_expr(constraint[:where])}" if constraint[:where]}" when :foreign_key sql = super if constraint[:not_valid] sql << " NOT VALID" end sql else super end end
Convert the hash of named conversion procs into a hash a oid conversion procs.
# File lib/sequel/adapters/shared/postgres.rb, line 643 def convert_named_procs_to_procs(named_procs) h = {} from(:pg_type).where(:typtype=>'b', :typname=>named_procs.keys.map{|t| t.to_s}).select_map([:oid, :typname]).each do |oid, name| h[oid.to_i] = named_procs[name.untaint.to_sym] end h end
Copy the conversion procs related to the given oids from PG_TYPES into the conversion procs for this instance.
# File lib/sequel/adapters/shared/postgres.rb, line 653 def copy_conversion_procs(oids) procs = conversion_procs oids.each do |oid| procs[oid] = PG_TYPES[oid] end end
SQL for doing fast table insert from stdin.
# File lib/sequel/adapters/shared/postgres.rb, line 685 def copy_into_sql(table, opts) sql = "COPY #{literal(table)}" if cols = opts[:columns] sql << literal(Array(cols)) end sql << " FROM STDIN" if opts[:options] || opts[:format] sql << " (" sql << "FORMAT #{opts[:format]}" if opts[:format] sql << "#{', ' if opts[:format]}#{opts[:options]}" if opts[:options] sql << ')' end sql end
SQL for doing fast table output to stdout.
# File lib/sequel/adapters/shared/postgres.rb, line 701 def copy_table_sql(table, opts) if table.is_a?(String) table else if opts[:options] || opts[:format] options = " (" options << "FORMAT #{opts[:format]}" if opts[:format] options << "#{', ' if opts[:format]}#{opts[:options]}" if opts[:options] options << ')' end table = if table.is_a?(::Sequel::Dataset) "(#{table.sql})" else literal(table) end "COPY #{table} TO STDOUT#{options}" end end
SQL statement to create database function.
# File lib/sequel/adapters/shared/postgres.rb, line 721 def create_function_sql(name, definition, opts={}) args = opts[:args] if !opts[:args].is_a?(Array) || !opts[:args].any?{|a| Array(a).length == 3 and %w'OUT INOUT'.include?(a[2].to_s)} returns = opts[:returns] || 'void' end language = opts[:language] || 'SQL' <<-END CREATE#{' OR REPLACE' if opts[:replace]} FUNCTION #{name}#{sql_function_args(args)} #{"RETURNS #{returns}" if returns} LANGUAGE #{language} #{opts[:behavior].to_s.upcase if opts[:behavior]} #{'STRICT' if opts[:strict]} #{'SECURITY DEFINER' if opts[:security_definer]} #{"COST #{opts[:cost]}" if opts[:cost]} #{"ROWS #{opts[:rows]}" if opts[:rows]} #{opts[:set].map{|k,v| " SET #{k} = #{v}"}.join("\n") if opts[:set]} AS #{literal(definition.to_s)}#{", #{literal(opts[:link_symbol].to_s)}" if opts[:link_symbol]} END end
SQL for creating a procedural language.
# File lib/sequel/adapters/shared/postgres.rb, line 742 def create_language_sql(name, opts={}) "CREATE#{' OR REPLACE' if opts[:replace] && server_version >= 90000}#{' TRUSTED' if opts[:trusted]} LANGUAGE #{name}#{" HANDLER #{opts[:handler]}" if opts[:handler]}#{" VALIDATOR #{opts[:validator]}" if opts[:validator]}" end
SQL for creating a schema.
# File lib/sequel/adapters/shared/postgres.rb, line 747 def create_schema_sql(name) "CREATE SCHEMA #{quote_identifier(name)}" end
Use a PostgreSQL-specific create table generator
# File lib/sequel/adapters/shared/postgres.rb, line 763 def create_table_generator_class Postgres::CreateTableGenerator end
DDL statement for creating a table with the given name, columns, and options
# File lib/sequel/adapters/shared/postgres.rb, line 752 def create_table_prefix_sql(name, options) temp_or_unlogged_sql = if options[:temp] raise(Error, "can't provide both :temp and :unlogged to create_table") if options[:unlogged] temporary_table_sql elsif options[:unlogged] UNLOGGED end "CREATE #{temp_or_unlogged_sql}TABLE#{' IF NOT EXISTS' if options[:if_not_exists]} #{options[:temp] ? quote_identifier(name) : quote_schema_table(name)}" end
SQL for creating a database trigger.
# File lib/sequel/adapters/shared/postgres.rb, line 768 def create_trigger_sql(table, name, function, opts={}) events = opts[:events] ? Array(opts[:events]) : [:insert, :update, :delete] whence = opts[:after] ? 'AFTER' : 'BEFORE' "CREATE TRIGGER #{name} #{whence} #{events.map{|e| e.to_s.upcase}.join(' OR ')} ON #{quote_schema_table(table)}#{' FOR EACH ROW' if opts[:each_row]} EXECUTE PROCEDURE #{function}(#{Array(opts[:args]).map{|a| literal(a)}.join(', ')})" end
DDL fragment for initial part of CREATE VIEW statement
# File lib/sequel/adapters/shared/postgres.rb, line 775 def create_view_prefix_sql(name, options) "CREATE #{'OR REPLACE 'if options[:replace]}#{'TEMPORARY 'if options[:temp]}VIEW #{quote_schema_table(name)}" end
The errors that the main adapters can raise, depends on the adapter being used
# File lib/sequel/adapters/shared/postgres.rb, line 780 def database_error_classes CONVERTED_EXCEPTIONS end
# File lib/sequel/adapters/shared/postgres.rb, line 680 def database_error_regexps DATABASE_ERROR_REGEXPS end
# File lib/sequel/adapters/shared/postgres.rb, line 661 def database_specific_error_class_from_sqlstate(sqlstate) if sqlstate == EXCLUSION_CONSTRAINT_SQL_STATE ExclusionConstraintViolation else super end end
SQL for dropping a function from the database.
# File lib/sequel/adapters/shared/postgres.rb, line 785 def drop_function_sql(name, opts={}) "DROP FUNCTION#{' IF EXISTS' if opts[:if_exists]} #{name}#{sql_function_args(opts[:args])}#{' CASCADE' if opts[:cascade]}" end
Support :if_exists, :cascade, and :concurrently options.
# File lib/sequel/adapters/shared/postgres.rb, line 790 def drop_index_sql(table, op) "DROP INDEX#{' CONCURRENTLY' if op[:concurrently]}#{' IF EXISTS' if op[:if_exists]} #{quote_identifier(op[:name] || default_index_name(table, op[:columns]))}#{' CASCADE' if op[:cascade]}" end
SQL for dropping a procedural language from the database.
# File lib/sequel/adapters/shared/postgres.rb, line 795 def drop_language_sql(name, opts={}) "DROP LANGUAGE#{' IF EXISTS' if opts[:if_exists]} #{name}#{' CASCADE' if opts[:cascade]}" end
SQL for dropping a schema from the database.
# File lib/sequel/adapters/shared/postgres.rb, line 800 def drop_schema_sql(name, opts={}) "DROP SCHEMA#{' IF EXISTS' if opts[:if_exists]} #{quote_identifier(name)}#{' CASCADE' if opts[:cascade]}" end
SQL for dropping a trigger from the database.
# File lib/sequel/adapters/shared/postgres.rb, line 805 def drop_trigger_sql(table, name, opts={}) "DROP TRIGGER#{' IF EXISTS' if opts[:if_exists]} #{name} ON #{quote_schema_table(table)}#{' CASCADE' if opts[:cascade]}" end
If opts includes a :schema option, or a default schema is used, restrict the dataset to that schema. Otherwise, just exclude the default PostgreSQL schemas except for public.
# File lib/sequel/adapters/shared/postgres.rb, line 811 def filter_schema(ds, opts) if schema = opts[:schema] || _default_schema ds.filter(:pg_namespace__nspname=>schema.to_s) else ds.exclude(:pg_namespace__nspname=>EXCLUDE_SCHEMAS) end end
Return a hash with oid keys and callable values, used for converting types.
# File lib/sequel/adapters/shared/postgres.rb, line 820 def get_conversion_procs procs = PG_TYPES.dup procs[1184] = procs[1114] = method(:to_application_timestamp) add_named_conversion_procs(procs, PG_NAMED_TYPES) procs end
PostgreSQL folds unquoted identifiers to lowercase, so it shouldn't need to upcase identifiers on input.
# File lib/sequel/adapters/shared/postgres.rb, line 828 def identifier_input_method_default nil end
PostgreSQL folds unquoted identifiers to lowercase, so it shouldn't need to upcase identifiers on output.
# File lib/sequel/adapters/shared/postgres.rb, line 833 def identifier_output_method_default nil end
PostgreSQL specific index SQL.
# File lib/sequel/adapters/shared/postgres.rb, line 838 def index_definition_sql(table_name, index) cols = index[:columns] index_name = index[:name] || default_index_name(table_name, cols) expr = if o = index[:opclass] "(#{Array(cols).map{|c| "#{literal(c)} #{o}"}.join(', ')})" else literal(Array(cols)) end unique = "UNIQUE " if index[:unique] index_type = index[:type] filter = index[:where] || index[:filter] filter = " WHERE #{filter_expr(filter)}" if filter case index_type when :full_text expr = "(to_tsvector(#{literal(index[:language] || 'simple')}::regconfig, #{literal(dataset.send(:full_text_string_join, cols))}))" index_type = :gin when :spatial index_type = :gist end "CREATE #{unique}INDEX#{' CONCURRENTLY' if index[:concurrently]} #{quote_identifier(index_name)} ON #{quote_schema_table(table_name)} #{"USING #{index_type} " if index_type}#{expr}#{filter}" end
Setup datastructures shared by all postgres adapters.
# File lib/sequel/adapters/shared/postgres.rb, line 861 def initialize_postgres_adapter @primary_keys = {} @primary_key_sequences = {} @conversion_procs = PG_TYPES.dup reset_conversion_procs end
Backbone of the tables and views support.
# File lib/sequel/adapters/shared/postgres.rb, line 869 def pg_class_relname(type, opts) ds = metadata_dataset.from(:pg_class).filter(:relkind=>type).select(:relname).exclude(SQL::StringExpression.like(:relname, SYSTEM_TABLE_REGEXP)).server(opts[:server]).join(:pg_namespace, :oid=>:relnamespace) ds = filter_schema(ds, opts) m = output_identifier_meth if block_given? yield(ds) elsif opts[:qualify] ds.select_append(:pg_namespace__nspname).map{|r| Sequel.qualify(m.call(r[:nspname]), m.call(r[:relname]))} else ds.map{|r| m.call(r[:relname])} end end
Use a dollar sign instead of question mark for the argument placeholder.
# File lib/sequel/adapters/shared/postgres.rb, line 884 def prepared_arg_placeholder PREPARED_ARG_PLACEHOLDER end
Return an expression the oid for the table expr. Used by the metadata parsing code to disambiguate unqualified tables.
# File lib/sequel/adapters/shared/postgres.rb, line 890 def regclass_oid(expr, opts={}) if expr.is_a?(String) && !expr.is_a?(LiteralString) expr = Sequel.identifier(expr) end sch, table = schema_and_table(expr) sch ||= opts[:schema] if sch expr = Sequel.qualify(sch, table) end expr = if ds = opts[:dataset] ds.literal(expr) else literal(expr) end Sequel.cast(expr.to_s,:regclass).cast(:oid) end
Remove the cached entries for primary keys and sequences when a table is changed.
# File lib/sequel/adapters/shared/postgres.rb, line 912 def remove_cached_schema(table) tab = quote_schema_table(table) Sequel.synchronize do @primary_keys.delete(tab) @primary_key_sequences.delete(tab) end super end
SQL DDL statement for renaming a table. PostgreSQL doesn't allow you to change a table's schema in a rename table operation, so speciying a new schema in new_name will not have an effect.
# File lib/sequel/adapters/shared/postgres.rb, line 923 def rename_table_sql(name, new_name) "ALTER TABLE #{quote_schema_table(name)} RENAME TO #{quote_identifier(schema_and_table(new_name).last)}" end
PostgreSQL's autoincrementing primary keys are of type integer or bigint using a nextval function call as a default.
# File lib/sequel/adapters/shared/postgres.rb, line 929 def schema_autoincrementing_primary_key?(schema) super && schema[:default] =~ /\Anextval/io end
Recognize PostgreSQL interval type.
# File lib/sequel/adapters/shared/postgres.rb, line 934 def schema_column_type(db_type) case db_type when /\Ainterval\z/io :interval else super end end
The dataset used for parsing table schemas, using the pg_* system catalogs.
# File lib/sequel/adapters/shared/postgres.rb, line 944 def schema_parse_table(table_name, opts) m = output_identifier_meth(opts[:dataset]) ds = metadata_dataset.select(:pg_attribute__attname___name, SQL::Cast.new(:pg_attribute__atttypid, :integer).as(:oid), SQL::Cast.new(:basetype__oid, :integer).as(:base_oid), SQL::Function.new(:format_type, :basetype__oid, :pg_type__typtypmod).as(:db_base_type), SQL::Function.new(:format_type, :pg_type__oid, :pg_attribute__atttypmod).as(:db_type), SQL::Function.new(:pg_get_expr, :pg_attrdef__adbin, :pg_class__oid).as(:default), SQL::BooleanExpression.new(:NOT, :pg_attribute__attnotnull).as(:allow_null), SQL::Function.new(:COALESCE, SQL::BooleanExpression.from_value_pairs(:pg_attribute__attnum => SQL::Function.new(:ANY, :pg_index__indkey)), false).as(:primary_key)). from(:pg_class). join(:pg_attribute, :attrelid=>:oid). join(:pg_type, :oid=>:atttypid). left_outer_join(:pg_type___basetype, :oid=>:typbasetype). left_outer_join(:pg_attrdef, :adrelid=>:pg_class__oid, :adnum=>:pg_attribute__attnum). left_outer_join(:pg_index, :indrelid=>:pg_class__oid, :indisprimary=>true). filter(:pg_attribute__attisdropped=>false). filter{|o| o.pg_attribute__attnum > 0}. filter(:pg_class__oid=>regclass_oid(table_name, opts)). order(:pg_attribute__attnum) ds.map do |row| row[:default] = nil if blank_object?(row[:default]) if row[:base_oid] row[:domain_oid] = row[:oid] row[:oid] = row.delete(:base_oid) row[:db_domain_type] = row[:db_type] row[:db_type] = row.delete(:db_base_type) else row.delete(:base_oid) row.delete(:db_base_type) end row[:type] = schema_column_type(row[:db_type]) [m.call(row.delete(:name)), row] end end
Set the transaction isolation level on the given connection
# File lib/sequel/adapters/shared/postgres.rb, line 981 def set_transaction_isolation(conn, opts) level = opts.fetch(:isolation, transaction_isolation_level) read_only = opts[:read_only] deferrable = opts[:deferrable] if level || !read_only.nil? || !deferrable.nil? sql = "SET TRANSACTION" sql << " ISOLATION LEVEL #{Sequel::Database::TRANSACTION_ISOLATION_LEVELS[level]}" if level sql << " READ #{read_only ? 'ONLY' : 'WRITE'}" unless read_only.nil? sql << " #{'NOT ' unless deferrable}DEFERRABLE" unless deferrable.nil? log_connection_execute(conn, sql) end end
Turns an array of argument specifiers into an SQL fragment used for function arguments. See create_function_sql.
# File lib/sequel/adapters/shared/postgres.rb, line 995 def sql_function_args(args) "(#{Array(args).map{|a| Array(a).reverse.join(' ')}.join(', ')})" end
PostgreSQL can combine multiple alter table ops into a single query.
# File lib/sequel/adapters/shared/postgres.rb, line 1000 def supports_combining_alter_table_ops? true end
PostgreSQL supports CREATE OR REPLACE VIEW.
# File lib/sequel/adapters/shared/postgres.rb, line 1005 def supports_create_or_replace_view? true end
Handle bigserial type if :serial option is present
# File lib/sequel/adapters/shared/postgres.rb, line 1010 def type_literal_generic_bignum(column) column[:serial] ? :bigserial : super end
PostgreSQL uses the bytea data type for blobs
# File lib/sequel/adapters/shared/postgres.rb, line 1015 def type_literal_generic_file(column) :bytea end
Handle serial type if :serial option is present
# File lib/sequel/adapters/shared/postgres.rb, line 1020 def type_literal_generic_integer(column) column[:serial] ? :serial : super end
PostgreSQL prefers the text datatype. If a fixed size is requested, the char type is used. If the text type is specifically disallowed or there is a size specified, use the varchar type. Otherwise use the type type.
# File lib/sequel/adapters/shared/postgres.rb, line 1028 def type_literal_generic_string(column) if column[:fixed] "char(#{column[:size]||255})" elsif column[:text] == false or column[:size] "varchar(#{column[:size]||255})" else :text end end