7600aef48b
As a side benefit, fix an (non-user-visible) bug in display_s5(). Also fixed a bug where removing orphaned pages did not expire cached summary pages.
1055 lines
39 KiB
Ruby
1055 lines
39 KiB
Ruby
require 'active_record/connection_adapters/abstract_adapter'
|
|
|
|
begin
|
|
require_library_or_gem 'pg'
|
|
rescue LoadError => e
|
|
begin
|
|
require_library_or_gem 'postgres'
|
|
class PGresult
|
|
alias_method :nfields, :num_fields unless self.method_defined?(:nfields)
|
|
alias_method :ntuples, :num_tuples unless self.method_defined?(:ntuples)
|
|
alias_method :ftype, :type unless self.method_defined?(:ftype)
|
|
alias_method :cmd_tuples, :cmdtuples unless self.method_defined?(:cmd_tuples)
|
|
end
|
|
rescue LoadError
|
|
raise e
|
|
end
|
|
end
|
|
|
|
module ActiveRecord
|
|
class Base
|
|
# Establishes a connection to the database that's used by all Active Record objects
|
|
def self.postgresql_connection(config) # :nodoc:
|
|
config = config.symbolize_keys
|
|
host = config[:host]
|
|
port = config[:port] || 5432
|
|
username = config[:username].to_s if config[:username]
|
|
password = config[:password].to_s if config[:password]
|
|
|
|
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
|
|
def extract_limit(sql_type)
|
|
case sql_type
|
|
when /^bigint/i; 8
|
|
when /^smallint/i; 2
|
|
else super
|
|
end
|
|
end
|
|
|
|
# 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/
|
|
$1
|
|
# 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 <tt>:schema_order</tt> option.
|
|
# * <tt>:encoding</tt> - An optional client encoding that is used in a <tt>SET client_encoding TO <encoding></tt> call on the connection.
|
|
# * <tt>:min_messages</tt> - An optional client min messages that is used in a <tt>SET client_min_messages TO <min_messages></tt> 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
|
|
ADAPTER_NAME = 'PostgreSQL'.freeze
|
|
|
|
NATIVE_DATABASE_TYPES = {
|
|
:primary_key => "serial primary key".freeze,
|
|
: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" }
|
|
}
|
|
|
|
# Returns 'PostgreSQL' as adapter name for identification purposes.
|
|
def adapter_name
|
|
ADAPTER_NAME
|
|
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:
|
|
NATIVE_DATABASE_TYPES
|
|
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 = query('SHOW standard_conforming_strings')[0][0] rescue false
|
|
self.client_min_messages = client_min_messages_old
|
|
has_support
|
|
end
|
|
|
|
def supports_insert_with_returning?
|
|
postgresql_version >= 80200
|
|
end
|
|
|
|
def supports_ddl_transactions?
|
|
true
|
|
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
|
|
remove_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 supports_disable_referential_integrity?() #:nodoc:
|
|
version = query("SHOW server_version")[0][0].split('.')
|
|
(version[0].to_i >= 8 && version[1].to_i >= 1) ? true : false
|
|
rescue
|
|
return false
|
|
end
|
|
|
|
def disable_referential_integrity(&block) #:nodoc:
|
|
if supports_disable_referential_integrity?() then
|
|
execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} DISABLE TRIGGER ALL" }.join(";"))
|
|
end
|
|
yield
|
|
ensure
|
|
if supports_disable_referential_integrity?() then
|
|
execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} ENABLE TRIGGER ALL" }.join(";"))
|
|
end
|
|
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)
|
|
# Extract the table from the insert sql. Yuck.
|
|
table = sql.split(" ", 4)[2].gsub('"', '')
|
|
|
|
# Try an insert with 'returning id' if available (PG >= 8.2)
|
|
if supports_insert_with_returning?
|
|
pk, sequence_name = *pk_and_sequence_for(table) unless pk
|
|
if pk
|
|
id = select_value("#{sql} RETURNING #{quote_column_name(pk)}")
|
|
clear_query_cache
|
|
return id
|
|
end
|
|
end
|
|
|
|
# Otherwise, insert then grab last_insert_id.
|
|
if insert_id = super
|
|
insert_id
|
|
else
|
|
# If neither pk nor sequence name is given, look them up.
|
|
unless pk || sequence_name
|
|
pk, sequence_name = *pk_and_sequence_for(table)
|
|
end
|
|
|
|
# If a pk is given, fallback to default sequence name.
|
|
# Don't fetch last insert id for a table without a pk.
|
|
if pk && sequence_name ||= default_sequence_name(table, pk)
|
|
last_insert_id(table, sequence_name)
|
|
end
|
|
end
|
|
end
|
|
|
|
# create a 2D array representing the result set
|
|
def result_as_array(res) #:nodoc:
|
|
ary = []
|
|
for i in 0...res.ntuples do
|
|
ary << []
|
|
for j in 0...res.nfields do
|
|
ary[i] << res.getvalue(i,j)
|
|
end
|
|
end
|
|
return ary
|
|
end
|
|
|
|
|
|
# Queries the database and returns the results in an Array-like object
|
|
def query(sql, name = nil) #:nodoc:
|
|
log(sql, name) do
|
|
if @async
|
|
res = @connection.async_exec(sql)
|
|
else
|
|
res = @connection.exec(sql)
|
|
end
|
|
return result_as_array(res)
|
|
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.cmd_tuples
|
|
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
|
|
|
|
# ruby-pg defines Ruby constants for transaction status,
|
|
# ruby-postgres does not.
|
|
PQTRANS_IDLE = defined?(PGconn::PQTRANS_IDLE) ? PGconn::PQTRANS_IDLE : 0
|
|
|
|
# Check whether a transaction is active.
|
|
def transaction_active?
|
|
@connection.transaction_status != PQTRANS_IDLE
|
|
end
|
|
|
|
# Wrap a block in a transaction. Returns result of block.
|
|
def transaction(start_db_transaction = true)
|
|
transaction_open = false
|
|
begin
|
|
if block_given?
|
|
if start_db_transaction
|
|
begin_db_transaction
|
|
transaction_open = true
|
|
end
|
|
yield
|
|
end
|
|
rescue Exception => database_transaction_rollback
|
|
if transaction_open && transaction_active?
|
|
transaction_open = false
|
|
rollback_db_transaction
|
|
end
|
|
raise unless database_transaction_rollback.is_a? ActiveRecord::Rollback
|
|
end
|
|
ensure
|
|
if transaction_open && transaction_active?
|
|
begin
|
|
commit_db_transaction
|
|
rescue Exception => database_transaction_rollback
|
|
rollback_db_transaction
|
|
raise
|
|
end
|
|
end
|
|
end
|
|
|
|
|
|
# SCHEMA STATEMENTS ========================================
|
|
|
|
def recreate_database(name) #:nodoc:
|
|
drop_database(name)
|
|
create_database(name)
|
|
end
|
|
|
|
# Create a new PostgreSQL database. Options include <tt>:owner</tt>, <tt>:template</tt>,
|
|
# <tt>:encoding</tt>, <tt>:tablespace</tt>, and <tt>:connection_limit</tt> (note that MySQL uses
|
|
# <tt>:charset</tt> while PostgreSQL uses <tt>:encoding</tt>).
|
|
#
|
|
# Example:
|
|
# create_database config[:database], config
|
|
# create_database 'foo_development', :encoding => 'unicode'
|
|
def create_database(name, options = {})
|
|
options = options.reverse_merge(:encoding => "utf8")
|
|
|
|
option_string = options.symbolize_keys.sum do |key, value|
|
|
case key
|
|
when :owner
|
|
" OWNER = \"#{value}\""
|
|
when :template
|
|
" TEMPLATE = \"#{value}\""
|
|
when :encoding
|
|
" ENCODING = '#{value}'"
|
|
when :tablespace
|
|
" TABLESPACE = \"#{value}\""
|
|
when :connection_limit
|
|
" CONNECTION LIMIT = #{value}"
|
|
else
|
|
""
|
|
end
|
|
end
|
|
|
|
execute "CREATE DATABASE #{quote_table_name(name)}#{option_string}"
|
|
end
|
|
|
|
# Drops a PostgreSQL database
|
|
#
|
|
# Example:
|
|
# drop_database 'matt_development'
|
|
def drop_database(name) #:nodoc:
|
|
if postgresql_version >= 80200
|
|
execute "DROP DATABASE IF EXISTS #{quote_table_name(name)}"
|
|
else
|
|
begin
|
|
execute "DROP DATABASE #{quote_table_name(name)}"
|
|
rescue ActiveRecord::StatementInvalid
|
|
@logger.warn "#{name} database doesn't exist." if @logger
|
|
end
|
|
end
|
|
end
|
|
|
|
|
|
# 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)
|
|
schemas = schema_search_path.split(/,/).map { |p| quote(p) }.join(',')
|
|
result = query(<<-SQL, name)
|
|
SELECT distinct 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 i.relnamespace IN (SELECT oid FROM pg_namespace WHERE nspname IN (#{schemas}) )
|
|
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
|
|
|
|
# Returns the current database name.
|
|
def current_database
|
|
query('select current_database()')[0][0]
|
|
end
|
|
|
|
# Returns the current database encoding format.
|
|
def encoding
|
|
query(<<-end_sql)[0][0]
|
|
SELECT pg_encoding_to_char(pg_database.encoding) FROM pg_database
|
|
WHERE pg_database.datname LIKE '#{current_database}'
|
|
end_sql
|
|
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
|
|
quoted_sequence = quote_column_name(sequence)
|
|
|
|
select_value <<-end_sql, 'Reset sequence'
|
|
SELECT setval('#{quoted_sequence}', (SELECT COALESCE(MAX(#{quote_column_name pk})+(SELECT increment_by FROM #{quoted_sequence}), (SELECT min_value FROM #{quoted_sequence})) FROM #{quote_table_name(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,
|
|
CASE
|
|
WHEN split_part(def.adsrc, '''', 2) ~ '.' THEN
|
|
substr(split_part(def.adsrc, '''', 2),
|
|
strpos(split_part(def.adsrc, '''', 2), '.')+1)
|
|
ELSE split_part(def.adsrc, '''', 2)
|
|
END
|
|
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 #{quote_table_name(name)} RENAME TO #{quote_table_name(new_name)}"
|
|
end
|
|
|
|
# Adds a new column to the named table.
|
|
# See TableDefinition#column for details of the options you can use.
|
|
def add_column(table_name, column_name, type, options = {})
|
|
default = options[:default]
|
|
notnull = options[:null] == false
|
|
|
|
# Add the column.
|
|
execute("ALTER TABLE #{quote_table_name(table_name)} ADD COLUMN #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}")
|
|
|
|
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 = {})
|
|
quoted_table_name = quote_table_name(table_name)
|
|
|
|
begin
|
|
execute "ALTER TABLE #{quoted_table_name} ALTER COLUMN #{quote_column_name(column_name)} TYPE #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}"
|
|
rescue ActiveRecord::StatementInvalid => e
|
|
raise e if postgresql_version > 80000
|
|
# This is PostgreSQL 7.x, so we have to use a more arcane way of doing it.
|
|
begin
|
|
begin_db_transaction
|
|
tmp_column_name = "#{column_name}_ar_tmp"
|
|
add_column(table_name, tmp_column_name, type, options)
|
|
execute "UPDATE #{quoted_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
|
|
rescue
|
|
rollback_db_transaction
|
|
end
|
|
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 #{quote_table_name(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 #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote(default)} WHERE #{quote_column_name(column_name)} IS NULL")
|
|
end
|
|
execute("ALTER TABLE #{quote_table_name(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 #{quote_table_name(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'
|
|
|
|
case limit
|
|
when 1..2; 'smallint'
|
|
when 3..4, nil; 'integer'
|
|
when 5..8; 'bigint'
|
|
else raise(ActiveRecordError, "No integer type has byte size #{limit}. Use a numeric with precision 0 instead.")
|
|
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+ string 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) + $3.to_i
|
|
rescue
|
|
0
|
|
end
|
|
end
|
|
end
|
|
|
|
private
|
|
# The internal PostgreSQL identifier of the money data type.
|
|
MONEY_COLUMN_TYPE_OID = 790 #:nodoc:
|
|
|
|
# Connects to a PostgreSQL server and sets up the adapter depending on the
|
|
# connected server's characteristics.
|
|
def connect
|
|
@connection = PGconn.connect(*@connection_parameters)
|
|
PGconn.translate_results = false if PGconn.respond_to?(:translate_results=)
|
|
|
|
# Ignore async_exec and async_query when using postgres-pr.
|
|
@async = @config[:allow_concurrency] && @connection.respond_to?(:async_exec)
|
|
|
|
# Use escape string syntax if available. We cannot do this lazily when encountering
|
|
# the first string, because that could then break any transactions in progress.
|
|
# See: http://www.postgresql.org/docs/current/static/runtime-config-compatible.html
|
|
# If PostgreSQL doesn't know the standard_conforming_strings parameter then it doesn't
|
|
# support escape string syntax. Don't override the inherited quoted_string_prefix.
|
|
if supports_standard_conforming_strings?
|
|
self.class.instance_eval do
|
|
define_method(:quoted_string_prefix) { 'E' }
|
|
end
|
|
end
|
|
|
|
# Money type has a fixed precision of 10 in PostgreSQL 8.2 and below, and as of
|
|
# PostgreSQL 8.3 it has a fixed precision of 19. PostgreSQLColumn.extract_precision
|
|
# should know about this but can't detect it there, so deal with it here.
|
|
money_precision = (postgresql_version >= 80300) ? 19 : 10
|
|
PostgreSQLColumn.module_eval(<<-end_eval)
|
|
def extract_precision(sql_type)
|
|
if sql_type =~ /^money$/
|
|
#{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 = result_as_array(res)
|
|
fields = []
|
|
rows = []
|
|
if res.ntuples > 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.ftype(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
|