Diffstat (limited to 'vendor/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb') (more/less context) (ignore whitespace changes)
| -rw-r--r-- | vendor/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb | 847 |
1 files changed, 0 insertions, 847 deletions
diff --git a/vendor/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/vendor/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb deleted file mode 100644 index d5c6ca6..0000000 --- a/vendor/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb +++ b/dev/null @@ -1,847 +0,0 @@ -require 'active_record/connection_adapters/abstract_adapter' - -module ActiveRecord - class Base - # Establishes a connection to the database that's used by all Active Record objects - def self.postgresql_connection(config) # :nodoc: - require_library_or_gem 'postgres' unless self.class.const_defined?(:PGconn) - - config = config.symbolize_keys - host = config[:host] - port = config[:port] || 5432 - username = config[:username].to_s - password = config[:password].to_s - - if config.has_key?(:database) - database = config[:database] - else - raise ArgumentError, "No database specified. Missing argument: database." - end - - # The postgres drivers don't allow the creation of an unconnected PGconn object, - # so just pass a nil connection object for the time being. - ConnectionAdapters::PostgreSQLAdapter.new(nil, logger, [host, port, nil, nil, database, username, password], config) - end - end - - module ConnectionAdapters - # PostgreSQL-specific extensions to column definitions in a table. - class PostgreSQLColumn < Column #:nodoc: - # Instantiates a new PostgreSQL column definition in a table. - def initialize(name, default, sql_type = nil, null = true) - super(name, self.class.extract_value_from_default(default), sql_type, null) - end - - private - # Extracts the scale from PostgreSQL-specific data types. - def extract_scale(sql_type) - # Money type has a fixed scale of 2. - sql_type =~ /^money/ ? 2 : super - end - - # Extracts the precision from PostgreSQL-specific data types. - def extract_precision(sql_type) - # Actual code is defined dynamically in PostgreSQLAdapter.connect - # depending on the server specifics - super - end - - # Escapes binary strings for bytea input to the database. - def self.string_to_binary(value) - if PGconn.respond_to?(:escape_bytea) - self.class.module_eval do - define_method(:string_to_binary) do |value| - PGconn.escape_bytea(value) if value - end - end - else - self.class.module_eval do - define_method(:string_to_binary) do |value| - if value - result = '' - value.each_byte { |c| result << sprintf('\\\\%03o', c) } - result - end - end - end - end - self.class.string_to_binary(value) - end - - # Unescapes bytea output from a database to the binary string it represents. - def self.binary_to_string(value) - # In each case, check if the value actually is escaped PostgreSQL bytea output - # or an unescaped Active Record attribute that was just written. - if PGconn.respond_to?(:unescape_bytea) - self.class.module_eval do - define_method(:binary_to_string) do |value| - if value =~ /\\\d{3}/ - PGconn.unescape_bytea(value) - else - value - end - end - end - else - self.class.module_eval do - define_method(:binary_to_string) do |value| - if value =~ /\\\d{3}/ - result = '' - i, max = 0, value.size - while i < max - char = value[i] - if char == ?\\ - if value[i+1] == ?\\ - char = ?\\ - i += 1 - else - char = value[i+1..i+3].oct - i += 3 - end - end - result << char - i += 1 - end - result - else - value - end - end - end - end - self.class.binary_to_string(value) - end - - # Maps PostgreSQL-specific data types to logical Rails types. - def simplified_type(field_type) - case field_type - # Numeric and monetary types - when /^(?:real|double precision)$/ - :float - # Monetary types - when /^money$/ - :decimal - # Character types - when /^(?:character varying|bpchar)(?:\(\d+\))?$/ - :string - # Binary data types - when /^bytea$/ - :binary - # Date/time types - when /^timestamp with(?:out)? time zone$/ - :datetime - when /^interval$/ - :string - # Geometric types - when /^(?:point|line|lseg|box|"?path"?|polygon|circle)$/ - :string - # Network address types - when /^(?:cidr|inet|macaddr)$/ - :string - # Bit strings - when /^bit(?: varying)?(?:\(\d+\))?$/ - :string - # XML type - when /^xml$/ - :string - # Arrays - when /^\D+\[\]$/ - :string - # Object identifier types - when /^oid$/ - :integer - # Pass through all types that are not specific to PostgreSQL. - else - super - end - end - - # Extracts the value from a PostgreSQL column default definition. - def self.extract_value_from_default(default) - case default - # Numeric types - when /\A-?\d+(\.\d*)?\z/ - default - # Character types - when /\A'(.*)'::(?:character varying|bpchar|text)\z/m - $1 - # Character types (8.1 formatting) - when /\AE'(.*)'::(?:character varying|bpchar|text)\z/m - $1.gsub(/\\(\d\d\d)/) { $1.oct.chr } - # Binary data types - when /\A'(.*)'::bytea\z/m - $1 - # Date/time types - when /\A'(.+)'::(?:time(?:stamp)? with(?:out)? time zone|date)\z/ - $1 - when /\A'(.*)'::interval\z/ - $1 - # Boolean type - when 'true' - true - when 'false' - false - # Geometric types - when /\A'(.*)'::(?:point|line|lseg|box|"?path"?|polygon|circle)\z/ - $1 - # Network address types - when /\A'(.*)'::(?:cidr|inet|macaddr)\z/ - $1 - # Bit string types - when /\AB'(.*)'::"?bit(?: varying)?"?\z/ - $1 - # XML type - when /\A'(.*)'::xml\z/m - $1 - # Arrays - when /\A'(.*)'::"?\D+"?\[\]\z/ - $1 - # Object identifier types - when /\A-?\d+\z/ - $1 - else - # Anything else is blank, some user type, or some function - # and we can't know the value of that, so return nil. - nil - end - end - end - end - - module ConnectionAdapters - # The PostgreSQL adapter works both with the native C (http://ruby.scripting.ca/postgres/) and the pure - # Ruby (available both as gem and from http://rubyforge.org/frs/?group_id=234&release_id=1944) drivers. - # - # Options: - # - # * <tt>:host</tt> -- Defaults to localhost - # * <tt>:port</tt> -- Defaults to 5432 - # * <tt>:username</tt> -- Defaults to nothing - # * <tt>:password</tt> -- Defaults to nothing - # * <tt>:database</tt> -- The name of the database. No default, must be provided. - # * <tt>:schema_search_path</tt> -- 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. - # * <tt>:encoding</tt> -- An optional client encoding that is used in a SET client_encoding TO <encoding> call on the connection. - # * <tt>:min_messages</tt> -- An optional client min messages that is used in a SET client_min_messages TO <min_messages> call on the connection. - # * <tt>:allow_concurrency</tt> -- If true, use async query methods so Ruby threads don't deadlock; otherwise, use blocking query methods. - class PostgreSQLAdapter < AbstractAdapter - # Returns 'PostgreSQL' as adapter name for identification purposes. - def adapter_name - 'PostgreSQL' - end - - # Initializes and connects a PostgreSQL adapter. - def initialize(connection, logger, connection_parameters, config) - super(connection, logger) - @connection_parameters, @config = connection_parameters, config - - connect - end - - # Is this connection alive and ready for queries? - 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 - - # Close then reopen the connection. - def reconnect! - if @connection.respond_to?(:reset) - @connection.reset - configure_connection - else - disconnect! - connect - end - end - - # Close the connection. - def disconnect! - @connection.close rescue nil - end - - 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 - - # Does PostgreSQL support migrations? - def supports_migrations? - true - end - - # Does PostgreSQL support standard conforming strings? - 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. - client_min_messages_old = client_min_messages - self.client_min_messages = '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.client_min_messages = client_min_messages_old - has_support - end - - # Returns the configured supported identifier length supported by PostgreSQL, - # or report the default of 63 on PostgreSQL 7.x. - def table_alias_length - @table_alias_length ||= (postgresql_version >= 80000 ? query('SHOW max_identifier_length')[0][0].to_i : 63) - end - - # QUOTING ================================================== - - # Quotes PostgreSQL-specific data types for SQL input. - 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 - - # Quotes strings for use in SQL input in the postgres driver for better performance. - 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 - - # Quotes column names for use in SQL queries. - def quote_column_name(name) #:nodoc: - %("#{name}") - end - - # Quote date/time values for use in SQL input. Includes microseconds - # if the value is a Time responding to usec. - def quoted_date(value) #:nodoc: - if value.acts_like?(:time) && value.respond_to?(:usec) - "#{super}.#{sprintf("%06d", value.usec)}" - else - super - end - end - - # REFERENTIAL INTEGRITY ==================================== - - 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 - - # DATABASE STATEMENTS ====================================== - - # Executes a SELECT query and returns an array of rows. Each row is an - # array of field values. - def select_rows(sql, name = nil) - select_raw(sql, name).last - end - - # Executes an INSERT query and returns the new record's ID - 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 - - # Queries the database and returns the results in an Array or nil otherwise. - def query(sql, name = nil) #:nodoc: - log(sql, name) do - if @async - @connection.async_query(sql) - else - @connection.query(sql) - end - end - end - - # Executes an SQL statement, returning a PGresult object on success - # or raising a PGError exception otherwise. - def execute(sql, name = nil) - log(sql, name) do - if @async - @connection.async_exec(sql) - else - @connection.exec(sql) - end - end - end - - # Executes an UPDATE query and returns the number of affected tuples. - def update_sql(sql, name = nil) - super.cmdtuples - end - - # Begins a transaction. - def begin_db_transaction - execute "BEGIN" - end - - # Commits a transaction. - def commit_db_transaction - execute "COMMIT" - end - - # Aborts a transaction. - def rollback_db_transaction - execute "ROLLBACK" - end - - # SCHEMA STATEMENTS ======================================== - - # Returns the list of all tables in the schema search path or a specified schema. - 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 - - # Returns the list of all indexes for a table. - 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 - - # Returns the list of all column definitions for a table. - 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 - - # 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: http://www.postgresql.org/docs/current/static/ddl-schemas.html - # - # This should be not be called manually but set in database.yml. - def schema_search_path=(schema_csv) - if schema_csv - execute "SET search_path TO #{schema_csv}" - @schema_search_path = schema_csv - end - end - - # Returns the active schema search path. - def schema_search_path - @schema_search_path ||= query('SHOW search_path')[0][0] - end - - # Returns the current client message level. - def client_min_messages - query('SHOW client_min_messages')[0][0] - end - - # Set the client message level. - def client_min_messages=(level) - execute("SET client_min_messages TO '#{level}'") - end - - # Returns the sequence name for a table's primary key or some other specified key. - 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 - - # Resets the sequence of a table's primary key to the maximum value. - 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 - - # Returns a table's primary key and belonging sequence. - 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 - - # Renames a table. - def rename_table(name, new_name) - execute "ALTER TABLE #{name} RENAME TO #{new_name}" - end - - # Adds a column to a table. - def add_column(table_name, column_name, type, options = {}) - default = options[:default] - notnull = options[:null] == false - - # Add the column. - execute("ALTER TABLE #{table_name} ADD COLUMN #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit])}") - - change_column_default(table_name, column_name, default) if options_include_default?(options) - change_column_null(table_name, column_name, false, default) if notnull - end - - # Changes the column of a table. - def change_column(table_name, column_name, type, options = {}) - begin - execute "ALTER TABLE #{table_name} ALTER COLUMN #{quote_column_name(column_name)} TYPE #{type_to_sql(type, options[:limit], options[:precision], options[: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, options) - execute "UPDATE #{table_name} SET #{quote_column_name(tmp_column_name)} = CAST(#{quote_column_name(column_name)} AS #{type_to_sql(type, options[:limit], options[:precision], options[: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, options[:default]) if options_include_default?(options) - change_column_null(table_name, column_name, options[:null], options[:default]) if options.key?(:null) - end - - # Changes the default value of a table column. - 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 - - 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 - - # Renames a column in a table. - 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 - - # Drops an index from a table. - def remove_index(table_name, options = {}) - execute "DROP INDEX #{index_name(table_name, options)}" - end - - # Maps logical Rails types to PostgreSQL-specific data types. - 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 - - # 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") - 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 - - # 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. - def add_order_by_for_association_limiting!(sql, options) #:nodoc: - return sql if options[:order].blank? - - order = options[: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 - - protected - # Returns the version of the connected PostgreSQL version. - def postgresql_version - @postgresql_version ||= - if @connection.respond_to?(:server_version) - @connection.server_version - else - # Mimic PGconn.server_version behavior - begin - query('SELECT version()')[0][0] =~ /PostgreSQL (\d+)\.(\d+)\.(\d+)/ - ($1.to_i * 10000) + ($2.to_i * 100) + $3.to_i - rescue - 0 - end - end - end - - private - # The internal PostgreSQL identifer of the money data type. - MONEY_COLUMN_TYPE_OID = 790 #:nodoc: - - # Connects to a PostgreSQL server and sets up the adapter depending on the - # connected server's characteristics. - def connect - @connection = PGconn.connect(*@connection_parameters) - PGconn.translate_results = false if PGconn.respond_to?(:translate_results=) - - # Ignore async_exec and async_query when using postgres-pr. - @async = @config[:allow_concurrency] && @connection.respond_to?(:async_exec) - - # Use escape string syntax if available. We cannot do this lazily when encountering - # the first string, because that could then break any transactions in progress. - # See: http://www.postgresql.org/docs/current/static/runtime-config-compatible.html - # If PostgreSQL doesn't know the standard_conforming_strings parameter then it doesn't - # support escape string syntax. Don't override the inherited quoted_string_prefix. - if supports_standard_conforming_strings? - self.class.instance_eval do - define_method(:quoted_string_prefix) { 'E' } - end - end - - # Money type has a fixed precision of 10 in PostgreSQL 8.2 and below, and as of - # PostgreSQL 8.3 it has a fixed precision of 19. PostgreSQLColumn.extract_precision - # should know about this but can't detect it there, so deal with it here. - money_precision = (postgresql_version >= 80300) ? 19 : 10 - PostgreSQLColumn.module_eval(<<-end_eval) - def extract_precision(sql_type) - if sql_type =~ /^money$/ - #{money_precision} - else - super - end - end - end_eval - - configure_connection - end - - # Configures the encoding, verbosity, and schema search path of the connection. - # This is called by #connect and should not be called manually. - def configure_connection - if @config[:encoding] - if @connection.respond_to?(:set_client_encoding) - @connection.set_client_encoding(@config[:encoding]) - else - execute("SET client_encoding TO '#{@config[:encoding]}'") - end - end - self.client_min_messages = @config[:min_messages] if @config[:min_messages] - self.schema_search_path = @config[:schema_search_path] || @config[:schema_order] - end - - # Returns the current ID of a table's sequence. - def last_insert_id(table, sequence_name) #:nodoc: - Integer(select_value("SELECT currval('#{sequence_name}')")) - end - - # Executes a SELECT query and returns the results, performing any data type - # conversions that are required to be performed here instead of in PostgreSQLColumn. - def select(sql, name = nil) - fields, rows = select_raw(sql, name) - result = [] - for row in rows - row_hash = {} - fields.each_with_index do |f, i| - row_hash[f] = row[i] - end - result << row_hash - end - result - end - - def select_raw(sql, name = nil) - res = execute(sql, name) - results = res.result - fields = [] - rows = [] - if results.length > 0 - fields = res.fields - results.each do |row| - hashed_row = {} - row.each_index do |cell_index| - # If this is a money type column and there are any currency symbols, - # then strip them off. Indeed it would be prettier to do this in - # PostgreSQLColumn.string_to_decimal but would break form input - # fields that call value_before_type_cast. - if res.type(cell_index) == MONEY_COLUMN_TYPE_OID - # Because money output is formatted according to the locale, there are two - # cases to consider (note the decimal separators): - # (1) $12,345,678.12 - # (2) $12.345.678,12 - case column = row[cell_index] - when /^-?\D+[\d,]+\.\d{2}$/ # (1) - row[cell_index] = column.gsub(/[^-\d\.]/, '') - when /^-?\D+[\d\.]+,\d{2}$/ # (2) - row[cell_index] = column.gsub(/[^-\d,]/, '').sub(/,/, '.') - end - end - - hashed_row[fields[cell_index]] = column - end - rows << row - end - end - res.clear - return fields, rows - end - - # Returns the list of a table's column names, data types, and default values. - # - # The underlying query is roughly: - # SELECT column.name, column.type, default.value - # FROM column LEFT JOIN default - # ON column.table_id = default.table_id - # AND column.num = default.column_num - # WHERE column.table_id = get_table_id('table_name') - # AND column.num > 0 - # AND NOT column.is_dropped - # ORDER BY column.num - # - # If the table name is not prefixed with a schema, the database will - # take the first match from the schema search path. - # - # Query implementation notes: - # - format_type includes the column size constraint, e.g. varchar(50) - # - ::regclass is a function that gives the id for a table name - def column_definitions(table_name) #:nodoc: - query <<-end_sql - SELECT a.attname, format_type(a.atttypid, a.atttypmod), d.adsrc, a.attnotnull - FROM pg_attribute a LEFT JOIN pg_attrdef d - ON a.attrelid = d.adrelid AND a.attnum = d.adnum - WHERE a.attrelid = '#{table_name}'::regclass - AND a.attnum > 0 AND NOT a.attisdropped - ORDER BY a.attnum - end_sql - end - end - end -end |