Class: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
- Inherits:
-
AbstractAdapter
- Object
- AbstractAdapter
- ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
- Defined in:
- lib/active_record/connection_adapters/postgresql_adapter.rb
Overview
The PostgreSQL adapter works both with the native C (ruby.scripting.ca/postgres/) and the pure Ruby (available both as gem and from rubyforge.org/frs/?group_id=234&release_id=1944) drivers.
Options:
-
:host
– Defaults to localhost -
:port
– Defaults to 5432 -
:username
– Defaults to nothing -
:password
– Defaults to nothing -
:database
– The name of the database. No default, must be provided. -
:schema_search_path
– An optional schema search path for the connection given as a string of comma-separated schema names. This is backward-compatible with the :schema_order option. -
:encoding
– An optional client encoding that is used in a SET client_encoding TO <encoding> call on the connection. -
:min_messages
– An optional client min messages that is used in a SET client_min_messages TO <min_messages> call on the connection. -
:allow_concurrency
– If true, use async query methods so Ruby threads don’t deadlock; otherwise, use blocking query methods.
Instance Method Summary collapse
-
#active? ⇒ Boolean
Is this connection alive and ready for queries?.
-
#adapter_name ⇒ Object
Returns ‘PostgreSQL’ as adapter name for identification purposes.
-
#add_column(table_name, column_name, type, options = {}) ⇒ Object
Adds a column to a table.
-
#add_order_by_for_association_limiting!(sql, options) ⇒ Object
Returns an ORDER BY clause for the passed order option.
-
#begin_db_transaction ⇒ Object
Begins a transaction.
-
#change_column(table_name, column_name, type, options = {}) ⇒ Object
Changes the column of a table.
-
#change_column_default(table_name, column_name, default) ⇒ Object
Changes the default value of a table column.
- #change_column_null(table_name, column_name, null, default = nil) ⇒ Object
-
#client_min_messages ⇒ Object
Returns the current client message level.
-
#client_min_messages=(level) ⇒ Object
Set the client message level.
-
#columns(table_name, name = nil) ⇒ Object
Returns the list of all column definitions for a table.
-
#commit_db_transaction ⇒ Object
Commits a transaction.
-
#default_sequence_name(table_name, pk = nil) ⇒ Object
Returns the sequence name for a table’s primary key or some other specified key.
-
#disable_referential_integrity(&block) ⇒ Object
REFERENTIAL INTEGRITY ====================================.
-
#disconnect! ⇒ Object
Close the connection.
-
#distinct(columns, order_by) ⇒ Object
Returns a SELECT DISTINCT clause for a given set of columns and a given ORDER BY clause.
-
#execute(sql, name = nil) ⇒ Object
Executes an SQL statement, returning a PGresult object on success or raising a PGError exception otherwise.
-
#indexes(table_name, name = nil) ⇒ Object
Returns the list of all indexes for a table.
-
#initialize(connection, logger, connection_parameters, config) ⇒ PostgreSQLAdapter
constructor
Initializes and connects a PostgreSQL adapter.
-
#insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) ⇒ Object
Executes an INSERT query and returns the new record’s ID.
-
#native_database_types ⇒ Object
:nodoc:.
-
#pk_and_sequence_for(table) ⇒ Object
Returns a table’s primary key and belonging sequence.
-
#query(sql, name = nil) ⇒ Object
Queries the database and returns the results in an Array or nil otherwise.
-
#quote(value, column = nil) ⇒ Object
Quotes PostgreSQL-specific data types for SQL input.
-
#quote_column_name(name) ⇒ Object
Quotes column names for use in SQL queries.
-
#quote_string(s) ⇒ Object
Quotes strings for use in SQL input in the postgres driver for better performance.
-
#quoted_date(value) ⇒ Object
Quote date/time values for use in SQL input.
-
#reconnect! ⇒ Object
Close then reopen the connection.
-
#remove_index(table_name, options = {}) ⇒ Object
Drops an index from a table.
-
#rename_column(table_name, column_name, new_column_name) ⇒ Object
Renames a column in a table.
-
#rename_table(name, new_name) ⇒ Object
Renames a table.
-
#reset_pk_sequence!(table, pk = nil, sequence = nil) ⇒ Object
Resets the sequence of a table’s primary key to the maximum value.
-
#rollback_db_transaction ⇒ Object
Aborts a transaction.
-
#schema_search_path ⇒ Object
Returns the active schema search path.
-
#schema_search_path=(schema_csv) ⇒ Object
Sets the schema search path to a string of comma-separated schema names.
-
#select_rows(sql, name = nil) ⇒ Object
Executes a SELECT query and returns an array of rows.
-
#supports_migrations? ⇒ Boolean
Does PostgreSQL support migrations?.
-
#supports_standard_conforming_strings? ⇒ Boolean
Does PostgreSQL support standard conforming strings?.
-
#table_alias_length ⇒ Object
Returns the configured supported identifier length supported by PostgreSQL, or report the default of 63 on PostgreSQL 7.x.
-
#tables(name = nil) ⇒ Object
Returns the list of all tables in the schema search path or a specified schema.
-
#type_to_sql(type, limit = nil, precision = nil, scale = nil) ⇒ Object
Maps logical Rails types to PostgreSQL-specific data types.
-
#update_sql(sql, name = nil) ⇒ Object
Executes an UPDATE query and returns the number of affected tuples.
Methods inherited from AbstractAdapter
#log_info, #prefetch_primary_key?, #quote_table_name, #raw_connection, #requires_reloading?, #reset_runtime, #supports_count_distinct?, #verify!
Methods included from QueryCache
Methods included from Quoting
#quote_table_name, #quoted_false, #quoted_string_prefix, #quoted_true
Methods included from DatabaseStatements
#add_limit!, #add_limit_offset!, #add_lock!, #delete, #empty_insert_statement, #insert_fixture, #reset_sequence!, #select_all, #select_one, #select_value, #select_values, #transaction, #update
Methods included from SchemaStatements
#add_column_options!, #add_index, #create_table, #drop_table, #dump_schema_information, #index_name, #initialize_schema_information, #remove_column, #structure_dump, #table_alias_for
Constructor Details
#initialize(connection, logger, connection_parameters, config) ⇒ PostgreSQLAdapter
Initializes and connects a PostgreSQL adapter.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 233 def initialize(connection, logger, connection_parameters, config) super(connection, logger) @connection_parameters, @config = connection_parameters, config connect end |
Instance Method Details
#active? ⇒ Boolean
Is this connection alive and ready for queries?
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 241 def active? if @connection.respond_to?(:status) @connection.status == PGconn::CONNECTION_OK else # We're asking the driver, not ActiveRecord, so use @connection.query instead of #query @connection.query 'SELECT 1' true end # postgres-pr raises a NoMethodError when querying if no connection is available. rescue PGError, NoMethodError false end |
#adapter_name ⇒ Object
Returns ‘PostgreSQL’ as adapter name for identification purposes.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 228 def adapter_name 'PostgreSQL' end |
#add_column(table_name, column_name, type, options = {}) ⇒ Object
Adds a column to a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 589 def add_column(table_name, column_name, type, = {}) default = [:default] notnull = [:null] == false # Add the column. execute("ALTER TABLE #{table_name} ADD COLUMN #{quote_column_name(column_name)} #{type_to_sql(type, [:limit])}") change_column_default(table_name, column_name, default) if () change_column_null(table_name, column_name, false, default) if notnull end |
#add_order_by_for_association_limiting!(sql, options) ⇒ Object
Returns an ORDER BY clause for the passed order option.
PostgreSQL does not allow arbitrary ordering when using DISTINCT ON, so we work around this by wrapping the sql as a sub-select and ordering in that query.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 679 def add_order_by_for_association_limiting!(sql, ) #:nodoc: return sql if [:order].blank? order = [:order].split(',').collect { |s| s.strip }.reject(&:blank?) order.map! { |s| 'DESC' if s =~ /\bdesc$/i } order = order.zip((0...order.size).to_a).map { |s,i| "id_list.alias_#{i} #{s}" }.join(', ') sql.replace "SELECT * FROM (#{sql}) AS id_list ORDER BY #{order}" end |
#begin_db_transaction ⇒ Object
Begins a transaction.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 422 def begin_db_transaction execute "BEGIN" end |
#change_column(table_name, column_name, type, options = {}) ⇒ Object
Changes the column of a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 601 def change_column(table_name, column_name, type, = {}) begin execute "ALTER TABLE #{table_name} ALTER COLUMN #{quote_column_name(column_name)} TYPE #{type_to_sql(type, [:limit], [:precision], [:scale])}" rescue ActiveRecord::StatementInvalid # This is PostgreSQL 7.x, so we have to use a more arcane way of doing it. begin_db_transaction tmp_column_name = "#{column_name}_ar_tmp" add_column(table_name, tmp_column_name, type, ) execute "UPDATE #{table_name} SET #{quote_column_name(tmp_column_name)} = CAST(#{quote_column_name(column_name)} AS #{type_to_sql(type, [:limit], [:precision], [:scale])})" remove_column(table_name, column_name) rename_column(table_name, tmp_column_name, column_name) commit_db_transaction end change_column_default(table_name, column_name, [:default]) if () change_column_null(table_name, column_name, [:null], [:default]) if .key?(:null) end |
#change_column_default(table_name, column_name, default) ⇒ Object
Changes the default value of a table column.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 620 def change_column_default(table_name, column_name, default) execute "ALTER TABLE #{table_name} ALTER COLUMN #{quote_column_name(column_name)} SET DEFAULT #{quote(default)}" end |
#change_column_null(table_name, column_name, null, default = nil) ⇒ Object
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 624 def change_column_null(table_name, column_name, null, default = nil) unless null || default.nil? execute("UPDATE #{table_name} SET #{quote_column_name(column_name)}=#{quote(default)} WHERE #{quote_column_name(column_name)} IS NULL") end execute("ALTER TABLE #{table_name} ALTER #{quote_column_name(column_name)} #{null ? 'DROP' : 'SET'} NOT NULL") end |
#client_min_messages ⇒ Object
Returns the current client message level.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 508 def query('SHOW client_min_messages')[0][0] end |
#client_min_messages=(level) ⇒ Object
Set the client message level.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 513 def (level) execute("SET client_min_messages TO '#{level}'") end |
#columns(table_name, name = nil) ⇒ Object
Returns the list of all column definitions for a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 483 def columns(table_name, name = nil) # Limit, precision, and scale are all handled by the superclass. column_definitions(table_name).collect do |name, type, default, notnull| PostgreSQLColumn.new(name, default, type, notnull == 'f') end end |
#commit_db_transaction ⇒ Object
Commits a transaction.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 427 def commit_db_transaction execute "COMMIT" end |
#default_sequence_name(table_name, pk = nil) ⇒ Object
Returns the sequence name for a table’s primary key or some other specified key.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 518 def default_sequence_name(table_name, pk = nil) #:nodoc: default_pk, default_seq = pk_and_sequence_for(table_name) default_seq || "#{table_name}_#{pk || default_pk || 'id'}_seq" end |
#disable_referential_integrity(&block) ⇒ Object
REFERENTIAL INTEGRITY ====================================
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 372 def disable_referential_integrity(&block) #:nodoc: execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} DISABLE TRIGGER ALL" }.join(";")) yield ensure execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} ENABLE TRIGGER ALL" }.join(";")) end |
#disconnect! ⇒ Object
Close the connection.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 266 def disconnect! @connection.close rescue nil end |
#distinct(columns, order_by) ⇒ Object
Returns a SELECT DISTINCT clause for a given set of columns and a given ORDER BY clause.
PostgreSQL requires the ORDER BY columns in the select list for distinct queries, and requires that the ORDER BY include the distinct column.
distinct("posts.id", "posts.created_at desc")
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 660 def distinct(columns, order_by) #:nodoc: return "DISTINCT #{columns}" if order_by.blank? # Construct a clean list of column names from the ORDER BY clause, removing # any ASC/DESC modifiers order_columns = order_by.split(',').collect { |s| s.split.first } order_columns.delete_if &:blank? order_columns = order_columns.zip((0...order_columns.size).to_a).map { |s,i| "#{s} AS alias_#{i}" } # Return a DISTINCT ON() clause that's distinct on the columns we want but includes # all the required columns for the ORDER BY to work properly. sql = "DISTINCT ON (#{columns}) #{columns}, " sql << order_columns * ', ' end |
#execute(sql, name = nil) ⇒ Object
Executes an SQL statement, returning a PGresult object on success or raising a PGError exception otherwise.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 406 def execute(sql, name = nil) log(sql, name) do if @async @connection.async_exec(sql) else @connection.exec(sql) end end end |
#indexes(table_name, name = nil) ⇒ Object
Returns the list of all indexes for a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 449 def indexes(table_name, name = nil) result = query(<<-SQL, name) SELECT i.relname, d.indisunique, a.attname FROM pg_class t, pg_class i, pg_index d, pg_attribute a WHERE i.relkind = 'i' AND d.indexrelid = i.oid AND d.indisprimary = 'f' AND t.oid = d.indrelid AND t.relname = '#{table_name}' AND a.attrelid = t.oid AND ( d.indkey[0]=a.attnum OR d.indkey[1]=a.attnum OR d.indkey[2]=a.attnum OR d.indkey[3]=a.attnum OR d.indkey[4]=a.attnum OR d.indkey[5]=a.attnum OR d.indkey[6]=a.attnum OR d.indkey[7]=a.attnum OR d.indkey[8]=a.attnum OR d.indkey[9]=a.attnum ) ORDER BY i.relname SQL current_index = nil indexes = [] result.each do |row| if current_index != row[0] indexes << IndexDefinition.new(table_name, row[0], row[1] == "t", []) current_index = row[0] end indexes.last.columns << row[2] end indexes end |
#insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) ⇒ Object
Executes an INSERT query and returns the new record’s ID
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 388 def insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) table = sql.split(" ", 4)[2] super || last_insert_id(table, sequence_name || default_sequence_name(table, pk)) end |
#native_database_types ⇒ Object
:nodoc:
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 270 def native_database_types #:nodoc: { :primary_key => "serial primary key", :string => { :name => "character varying", :limit => 255 }, :text => { :name => "text" }, :integer => { :name => "integer" }, :float => { :name => "float" }, :decimal => { :name => "decimal" }, :datetime => { :name => "timestamp" }, :timestamp => { :name => "timestamp" }, :time => { :name => "time" }, :date => { :name => "date" }, :binary => { :name => "bytea" }, :boolean => { :name => "boolean" } } end |
#pk_and_sequence_for(table) ⇒ Object
Returns a table’s primary key and belonging sequence.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 542 def pk_and_sequence_for(table) #:nodoc: # First try looking for a sequence with a dependency on the # given table's primary key. result = query(<<-end_sql, 'PK and serial sequence')[0] SELECT attr.attname, seq.relname FROM pg_class seq, pg_attribute attr, pg_depend dep, pg_namespace name, pg_constraint cons WHERE seq.oid = dep.objid AND seq.relkind = 'S' AND attr.attrelid = dep.refobjid AND attr.attnum = dep.refobjsubid AND attr.attrelid = cons.conrelid AND attr.attnum = cons.conkey[1] AND cons.contype = 'p' AND dep.refobjid = '#{table}'::regclass end_sql if result.nil? or result.empty? # If that fails, try parsing the primary key's default value. # Support the 7.x and 8.0 nextval('foo'::text) as well as # the 8.1+ nextval('foo'::regclass). result = query(<<-end_sql, 'PK and custom sequence')[0] SELECT attr.attname, split_part(def.adsrc, '''', 2) FROM pg_class t JOIN pg_attribute attr ON (t.oid = attrelid) JOIN pg_attrdef def ON (adrelid = attrelid AND adnum = attnum) JOIN pg_constraint cons ON (conrelid = adrelid AND adnum = conkey[1]) WHERE t.oid = '#{table}'::regclass AND cons.contype = 'p' AND def.adsrc ~* 'nextval' end_sql end # [primary_key, sequence] [result.first, result.last] rescue nil end |
#query(sql, name = nil) ⇒ Object
Queries the database and returns the results in an Array or nil otherwise.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 394 def query(sql, name = nil) #:nodoc: log(sql, name) do if @async @connection.async_query(sql) else @connection.query(sql) end end end |
#quote(value, column = nil) ⇒ Object
Quotes PostgreSQL-specific data types for SQL input.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 317 def quote(value, column = nil) #:nodoc: if value.kind_of?(String) && column && column.type == :binary "#{quoted_string_prefix}'#{column.class.string_to_binary(value)}'" elsif value.kind_of?(String) && column && column.sql_type =~ /^xml$/ "xml '#{quote_string(value)}'" elsif value.kind_of?(Numeric) && column && column.sql_type =~ /^money$/ # Not truly string input, so doesn't require (or allow) escape string syntax. "'#{value.to_s}'" elsif value.kind_of?(String) && column && column.sql_type =~ /^bit/ case value when /^[01]*$/ "B'#{value}'" # Bit-string notation when /^[0-9A-F]*$/i "X'#{value}'" # Hexadecimal notation end else super end end |
#quote_column_name(name) ⇒ Object
Quotes column names for use in SQL queries.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 356 def quote_column_name(name) #:nodoc: %("#{name}") end |
#quote_string(s) ⇒ Object
Quotes strings for use in SQL input in the postgres driver for better performance.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 338 def quote_string(s) #:nodoc: if PGconn.respond_to?(:escape) self.class.instance_eval do define_method(:quote_string) do |s| PGconn.escape(s) end end else # There are some incorrectly compiled postgres drivers out there # that don't define PGconn.escape. self.class.instance_eval do undef_method(:quote_string) end end quote_string(s) end |
#quoted_date(value) ⇒ Object
Quote date/time values for use in SQL input. Includes microseconds if the value is a Time responding to usec.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 362 def quoted_date(value) #:nodoc: if value.acts_like?(:time) && value.respond_to?(:usec) "#{super}.#{sprintf("%06d", value.usec)}" else super end end |
#reconnect! ⇒ Object
Close then reopen the connection.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 255 def reconnect! if @connection.respond_to?(:reset) @connection.reset configure_connection else disconnect! connect end end |
#remove_index(table_name, options = {}) ⇒ Object
Drops an index from a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 637 def remove_index(table_name, = {}) execute "DROP INDEX #{index_name(table_name, )}" end |
#rename_column(table_name, column_name, new_column_name) ⇒ Object
Renames a column in a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 632 def rename_column(table_name, column_name, new_column_name) execute "ALTER TABLE #{table_name} RENAME COLUMN #{quote_column_name(column_name)} TO #{quote_column_name(new_column_name)}" end |
#rename_table(name, new_name) ⇒ Object
Renames a table.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 584 def rename_table(name, new_name) execute "ALTER TABLE #{name} RENAME TO #{new_name}" end |
#reset_pk_sequence!(table, pk = nil, sequence = nil) ⇒ Object
Resets the sequence of a table’s primary key to the maximum value.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 524 def reset_pk_sequence!(table, pk = nil, sequence = nil) #:nodoc: unless pk and sequence default_pk, default_sequence = pk_and_sequence_for(table) pk ||= default_pk sequence ||= default_sequence end if pk if sequence select_value <<-end_sql, 'Reset sequence' SELECT setval('#{sequence}', (SELECT COALESCE(MAX(#{pk})+(SELECT increment_by FROM #{sequence}), (SELECT min_value FROM #{sequence})) FROM #{table}), false) end_sql else @logger.warn "#{table} has primary key #{pk} with no default sequence" if @logger end end end |
#rollback_db_transaction ⇒ Object
Aborts a transaction.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 432 def rollback_db_transaction execute "ROLLBACK" end |
#schema_search_path ⇒ Object
Returns the active schema search path.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 503 def schema_search_path @schema_search_path ||= query('SHOW search_path')[0][0] end |
#schema_search_path=(schema_csv) ⇒ Object
Sets the schema search path to a string of comma-separated schema names. Names beginning with $ have to be quoted (e.g. $user => ‘$user’). See: www.postgresql.org/docs/current/static/ddl-schemas.html
This should be not be called manually but set in database.yml.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 495 def schema_search_path=(schema_csv) if schema_csv execute "SET search_path TO #{schema_csv}" @schema_search_path = schema_csv end end |
#select_rows(sql, name = nil) ⇒ Object
Executes a SELECT query and returns an array of rows. Each row is an array of field values.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 383 def select_rows(sql, name = nil) select_raw(sql, name).last end |
#supports_migrations? ⇒ Boolean
Does PostgreSQL support migrations?
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 288 def supports_migrations? true end |
#supports_standard_conforming_strings? ⇒ Boolean
Does PostgreSQL support standard conforming strings?
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 293 def supports_standard_conforming_strings? # Temporarily set the client message level above error to prevent unintentional # error messages in the logs when working on a PostgreSQL database server that # does not support standard conforming strings. = self. = 'panic' # postgres-pr does not raise an exception when client_min_messages is set higher # than error and "SHOW standard_conforming_strings" fails, but returns an empty # PGresult instead. has_support = execute('SHOW standard_conforming_strings')[0][0] rescue false self. = has_support end |
#table_alias_length ⇒ Object
Returns the configured supported identifier length supported by PostgreSQL, or report the default of 63 on PostgreSQL 7.x.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 310 def table_alias_length @table_alias_length ||= (postgresql_version >= 80000 ? query('SHOW max_identifier_length')[0][0].to_i : 63) end |
#tables(name = nil) ⇒ Object
Returns the list of all tables in the schema search path or a specified schema.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 439 def tables(name = nil) schemas = schema_search_path.split(/,/).map { |p| quote(p) }.join(',') query(<<-SQL, name).map { |row| row[0] } SELECT tablename FROM pg_tables WHERE schemaname IN (#{schemas}) SQL end |
#type_to_sql(type, limit = nil, precision = nil, scale = nil) ⇒ Object
Maps logical Rails types to PostgreSQL-specific data types.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 642 def type_to_sql(type, limit = nil, precision = nil, scale = nil) return super unless type.to_s == 'integer' if limit.nil? || limit == 4 'integer' elsif limit < 4 'smallint' else 'bigint' end end |
#update_sql(sql, name = nil) ⇒ Object
Executes an UPDATE query and returns the number of affected tuples.
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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 417 def update_sql(sql, name = nil) super.cmdtuples end |