Module: ArJdbc::PostgreSQL

Included in:
ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
Defined in:
lib/arjdbc/postgresql/adapter.rb,
lib/arjdbc/postgresql/column.rb,
lib/arjdbc/postgresql/oid_types.rb

Overview

Strives to provide Rails built-in PostgreSQL adapter (API) compatibility.

Constant Summary collapse

ADAPTER_NAME = 
'PostgreSQL'.freeze
NATIVE_DATABASE_TYPES = 
{
  bigserial:    'bigserial',
  primary_key:  'serial primary key',
  bigint:       { name: 'bigint' },
  binary:       { name: 'bytea' },
  bit:          { name: 'bit' },
  bit_varying:  { name: 'bit varying' },
  boolean:      { name: 'boolean' },
  box:          { name: 'box' },
  char:         { name: 'char' },
  cidr:         { name: 'cidr' },
  circle:       { name: 'circle' },
  citext:       { name: 'citext' },
  date:         { name: 'date' },
  daterange:    { name: 'daterange' },
  datetime:     { name: 'timestamp' },
  decimal:      { name: 'decimal' }, # :limit => 1000
  float:        { name: 'float' },
  hstore:       { name: 'hstore' },
  inet:         { name: 'inet' },
  int4range:    { name: 'int4range' },
  int8range:    { name: 'int8range' },
  integer:      { name: 'integer' },
  interval:     { name: 'interval' }, # This doesn't get added to AR's postgres adapter until 5.1 but it fixes broken tests in 5.0 ...
  json:         { name: 'json' },
  jsonb:        { name: 'jsonb' },
  line:         { name: 'line' },
  lseg:         { name: 'lseg' },
  ltree:        { name: 'ltree' },
  macaddr:      { name: 'macaddr' },
  money:        { name: 'money' },
  numeric:      { name: 'numeric' },
  numrange:     { name: 'numrange' },
  path:         { name: 'path' },
  point:        { name: 'point' },
  polygon:      { name: 'polygon' },
  serial:       { name: 'serial' }, # auto-inc integer, bigserial, smallserial
  string:       { name: 'character varying' },
  text:         { name: 'text' },
  time:         { name: 'time' },
  timestamp:    { name: 'timestamp' },
  tsrange:      { name: 'tsrange' },
  tstzrange:    { name: 'tstzrange' },
  tsvector:     { name: 'tsvector' },
  uuid:         { name: 'uuid' },
  xml:          { name: 'xml' }
}

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.jdbc_connection_class ⇒ Object

See Also:



39
40
41
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 39

def self.jdbc_connection_class
  ::ActiveRecord::ConnectionAdapters::PostgreSQLJdbcConnection
end

Instance Method Details

#adapter_name ⇒ Object 



48
49
50
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 48

def adapter_name
  ADAPTER_NAME
end

#add_order_by_for_association_limiting!(sql, options) ⇒ Object

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.



401
402
403
404
405
406
407
408
409
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 401

def add_order_by_for_association_limiting!(sql, options)
  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

#all_schemas ⇒ Object 



377
378
379
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 377

def all_schemas
  select('SELECT nspname FROM pg_namespace').map { |row| row["nspname"] }
end

#clear_cache! ⇒ Object

We need to make sure to deallocate all the prepared statements since apparently calling close on the statement object doesn't always free the server resources and calling 'DISCARD ALL' fails if we are inside a transaction



360
361
362
363
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 360

def clear_cache!
  super
  @connection.execute 'DEALLOCATE ALL' if supports_statement_cache? && @connection.active?
end

#client_min_messages ⇒ Object

Returns the current client message level.



382
383
384
385
386
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 382

def client_min_messages
  return nil if redshift? # not supported on Redshift
  # Need to use #execute so we don't try to access the type map before it is initialized
  execute('SHOW client_min_messages', 'SCHEMA').values.first.first
end

#client_min_messages=(level) ⇒ Object

Set the client message level.



389
390
391
392
393
394
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 389

def client_min_messages=(level)
  # NOTE: for now simply ignore the writer (no warn on Redshift) so that
  # the AR copy-pasted PpstgreSQL parts stay the same as much as possible
  return nil if redshift? # not supported on Redshift
  execute("SET client_min_messages TO '#{level}'", 'SCHEMA')
end

#configure_connection ⇒ Object

Configures the encoding, verbosity, schema search path, and time zone of the connection. This is called on connection.connect and should not be called manually.



89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 89

def configure_connection
  #if encoding = config[:encoding]
    # The client_encoding setting is set by the driver and should not be altered.
    # If the driver detects a change it will abort the connection.
    # see http://jdbc.postgresql.org/documentation/91/connect.html
    # self.set_client_encoding(encoding)
  #end
  self.client_min_messages = config[:min_messages] || 'warning'
  self.schema_search_path = config[:schema_search_path] || config[:schema_order]

  # Use standard-conforming strings if available so we don't have to do the E'...' dance.
  set_standard_conforming_strings

  # If using Active Record's time zone support configure the connection to return
  # TIMESTAMP WITH ZONE types in UTC.
  # (SET TIME ZONE does not use an equals sign like other SET variables)
  if ActiveRecord::Base.default_timezone == :utc
    execute("SET time zone 'UTC'", 'SCHEMA')
  elsif tz = local_tz
    execute("SET time zone '#{tz}'", 'SCHEMA')
  end unless redshift?

  # SET statements from :variables config hash
  # http://www.postgresql.org/docs/8.3/static/sql-set.html
  (config[:variables] || {}).map do |k, v|
    if v == ':default' || v == :default
      # Sets the value to the global or compile default
      execute("SET SESSION #{k} TO DEFAULT", 'SCHEMA')
    elsif ! v.nil?
      execute("SET SESSION #{k} TO #{quote(v)}", 'SCHEMA')
    end
  end
end

#disable_extension(name) ⇒ Object 



267
268
269
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 267

def disable_extension(name)
  execute("DROP EXTENSION IF EXISTS \"#{name}\" CASCADE")
end

#enable_extension(name) ⇒ Object 



263
264
265
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 263

def enable_extension(name)
  execute("CREATE EXTENSION IF NOT EXISTS \"#{name}\"")
end

#escape_bytea(string) ⇒ Object

Note:

quote_string implemented as native



413
414
415
416
417
418
419
420
421
422
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 413

def escape_bytea(string)
  return unless string
  if supports_hex_escaped_bytea?
    "\\x#{string.unpack("H*")[0]}"
  else
    result = ''
    string.each_byte { |c| result << sprintf('\\\\%03o', c) }
    result
  end
end

#exec_insert(sql, name, binds, pk = nil, sequence_name = nil) ⇒ Object 



321
322
323
324
325
326
327
328
329
330
331
332
333
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 321

def exec_insert(sql, name, binds, pk = nil, sequence_name = nil)
  val = super
  if !use_insert_returning? && pk
    unless sequence_name
      table_ref = extract_table_ref_from_insert_sql(sql)
      sequence_name = default_sequence_name(table_ref, pk)
      return val unless sequence_name
    end
    last_insert_id_result(sequence_name)
  else
    val
  end
end

#explain(arel, binds = []) ⇒ Object 



335
336
337
338
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 335

def explain(arel, binds = [])
  sql = "EXPLAIN #{to_sql(arel, binds)}"
  ActiveRecord::ConnectionAdapters::PostgreSQL::ExplainPrettyPrinter.new.pp(exec_query(sql, 'EXPLAIN', binds))
end

#extension_enabled?(name) ⇒ Boolean

Returns:

  • (Boolean) 


271
272
273
274
275
276
277
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 271

def extension_enabled?(name)
  if supports_extensions?
    rows = select_rows("SELECT EXISTS(SELECT * FROM pg_available_extensions WHERE name = '#{name}' AND installed_version IS NOT NULL)", 'SCHEMA')
    available = rows.first.first # true/false or 't'/'f'
    available == true || available == 't'
  end
end

#extensions ⇒ Object 



279
280
281
282
283
284
285
286
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 279

def extensions
  if supports_extensions?
    rows = select_rows "SELECT extname from pg_extension", "SCHEMA"
    rows.map { |row| row.first }
  else
    []
  end
end

#get_advisory_lock(lock_id) ⇒ Object

Came from postgres_adapter



299
300
301
302
303
304
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 299

def get_advisory_lock(lock_id) # :nodoc:
  unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
    raise(ArgumentError, "Postgres requires advisory lock ids to be a signed 64 bit integer")
  end
  select_value("SELECT pg_try_advisory_lock(#{lock_id});")
end

#index_algorithms ⇒ Object 



288
289
290
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 288

def index_algorithms
  { :concurrently => 'CONCURRENTLY' }
end

#indexes(table_name, name = nil) ⇒ Object

Returns an array of indexes for the given table.



484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 484

def indexes(table_name, name = nil)
  # FIXME: AR version => table = Utils.extract_schema_qualified_name(table_name.to_s)
  schema, table = extract_schema_and_table(table_name.to_s)

  result = query(<<-SQL, 'SCHEMA')
        SELECT distinct i.relname, d.indisunique, d.indkey, pg_get_indexdef(d.indexrelid), t.oid,
                        pg_catalog.obj_description(i.oid, 'pg_class') AS comment,
        (SELECT COUNT(*) FROM pg_opclass o
           JOIN (SELECT unnest(string_to_array(d.indclass::text, ' '))::int oid) c
             ON o.oid = c.oid WHERE o.opcdefault = 'f')
        FROM pg_class t
        INNER JOIN pg_index d ON t.oid = d.indrelid
        INNER JOIN pg_class i ON d.indexrelid = i.oid
        LEFT JOIN pg_namespace n ON n.oid = i.relnamespace
        WHERE i.relkind = 'i'
          AND d.indisprimary = 'f'
          AND t.relname = '#{table}'
          AND n.nspname = #{schema ? "'#{schema}'" : 'ANY (current_schemas(false))'}
        ORDER BY i.relname
  SQL

  result.map do |row|
    index_name = row[0]
    # FIXME: These values [1,2] are returned in a different format than AR expects, maybe we could update it on the Java side to be more accurate
    unique = row[1].is_a?(String) ? row[1] == 't' : row[1] # JDBC gets us a boolean
    indkey = row[2].is_a?(Java::OrgPostgresqlUtil::PGobject) ? row[2].value : row[2]
    indkey = indkey.split(" ").map(&:to_i)
    inddef = row[3]
    oid = row[4]
    comment = row[5]
    opclass = row[6]

    using, expressions, where = inddef.scan(/ USING (\w+?) \((.+?)\)(?: WHERE (.+))?\z/).flatten

    if indkey.include?(0) || opclass > 0
      columns = expressions
    else
      columns = Hash[query(<<-SQL.strip_heredoc, "SCHEMA")].values_at(*indkey).compact
            SELECT a.attnum, a.attname
            FROM pg_attribute a
            WHERE a.attrelid = #{oid}
            AND a.attnum IN (#{indkey.join(",")})
      SQL

      # add info on sort order for columns (only desc order is explicitly specified, asc is the default)
      orders = Hash[
          expressions.scan(/(\w+) DESC/).flatten.map { |order_column| [order_column, :desc] }
      ]
    end

    IndexDefinition.new(table_name, index_name, unique, columns, [], orders, where, nil, using.to_sym, comment.presence)
  end.compact
end

#jdbc_column_class ⇒ Object

See Also:



44
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 44

def jdbc_column_class; ::ActiveRecord::ConnectionAdapters::PostgreSQLColumn end

#last_insert_id_result(sequence_name) ⇒ Object 



373
374
375
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 373

def last_insert_id_result(sequence_name)
  exec_query("SELECT currval('#{sequence_name}')", 'SQL')
end

#max_identifier_length ⇒ Object Also known as: table_alias_length, index_name_length

Returns the configured supported identifier length supported by PostgreSQL



315
316
317
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 315

def max_identifier_length
  @max_identifier_length ||= select_one('SHOW max_identifier_length', 'SCHEMA'.freeze)['max_identifier_length'].to_i
end

#native_database_types ⇒ Object 



174
175
176
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 174

def native_database_types
  NATIVE_DATABASE_TYPES
end

#postgresql_version ⇒ Object

TODO: Update this to pull info from the DatabaseMetaData object?



53
54
55
56
57
58
59
60
61
62
63
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 53

def postgresql_version
  @postgresql_version ||=
    begin
      version = @connection.database_product
      if version =~ /PostgreSQL (\d+)\.(\d+)\.(\d+)/
        ($1.to_i * 10000) + ($2.to_i * 100) + $3.to_i
      else
        0
      end
    end
end

#quote_table_name(name) ⇒ Object 



425
426
427
428
429
430
431
432
433
434
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 425

def quote_table_name(name)
  schema, name_part = extract_pg_identifier_from_name(name.to_s)

  unless name_part
    quote_column_name(schema)
  else
    table_name, name_part = extract_pg_identifier_from_name(name_part)
    "#{quote_column_name(schema)}.#{quote_column_name(table_name)}"
  end
end

#release_advisory_lock(lock_id) ⇒ Object

Came from postgres_adapter



307
308
309
310
311
312
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 307

def release_advisory_lock(lock_id) # :nodoc:
  unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
    raise(ArgumentError, "Postgres requires advisory lock ids to be a signed 64 bit integer")
  end
  select_value("SELECT pg_advisory_unlock(#{lock_id})")
end

#remove_column(table_name, column_name, type = nil, options = {}) ⇒ Object

Need to clear the cache even though the AR adapter doesn't for some reason



440
441
442
443
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 440

def remove_column(table_name, column_name, type = nil, options = {})
  super
  clear_cache!
end

#reset! ⇒ Object 



365
366
367
368
369
370
371
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 365

def reset!
  clear_cache!
  reset_transaction
  @connection.rollback # Have to deal with rollbacks differently than the AR adapter
  @connection.execute 'DISCARD ALL'
  @connection.configure_connection
end

#session_auth=(user) ⇒ Object

Set the authorized user for this session.



293
294
295
296
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 293

def session_auth=(user)
  clear_cache!
  execute "SET SESSION AUTHORIZATION #{user}"
end

#set_client_encoding(encoding) ⇒ Object 



82
83
84
85
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 82

def set_client_encoding(encoding)
  ActiveRecord::Base.logger.warn "client_encoding is set by the driver and should not be altered, ('#{encoding}' ignored)"
  ActiveRecord::Base.logger.debug "Set the 'allowEncodingChanges' driver property (e.g. using config[:properties]) if you need to override the client encoding when doing a copy."
end

#set_standard_conforming_strings ⇒ Object

Enable standard-conforming strings if available.



183
184
185
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 183

def set_standard_conforming_strings
  self.standard_conforming_strings=(true)
end

#standard_conforming_strings=(enable) ⇒ Object

Enable standard-conforming strings if available.



188
189
190
191
192
193
194
195
196
197
198
199
200
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 188

def standard_conforming_strings=(enable)
  client_min_messages = self.client_min_messages
  begin
    self.client_min_messages = 'panic'
    value = enable ? "on" : "off"
    execute("SET standard_conforming_strings = #{value}", 'SCHEMA')
    @standard_conforming_strings = ( value == "on" )
  rescue
    @standard_conforming_strings = :unsupported
  ensure
    self.client_min_messages = client_min_messages
  end
end

#standard_conforming_strings? ⇒ Boolean

Returns:

  • (Boolean) 


202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 202

def standard_conforming_strings?
  if @standard_conforming_strings.nil?
    client_min_messages = self.client_min_messages
    begin
      self.client_min_messages = 'panic'
      value = select_one('SHOW standard_conforming_strings', 'SCHEMA')['standard_conforming_strings']
      @standard_conforming_strings = ( value == "on" )
    rescue
      @standard_conforming_strings = :unsupported
    ensure
      self.client_min_messages = client_min_messages
    end
  end
  @standard_conforming_strings == true # return false if :unsupported
end

#supports_ddl_transactions? ⇒ Boolean

Returns:

  • (Boolean) 


218
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 218

def supports_ddl_transactions?; true end

#supports_explain? ⇒ Boolean

Returns:

  • (Boolean) 


220
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 220

def supports_explain?; true end

#supports_expression_index? ⇒ Boolean

Returns:

  • (Boolean) 


222
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 222

def supports_expression_index?; true end

#supports_extensions? ⇒ Boolean

Returns:

  • (Boolean) 


259
260
261
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 259

def supports_extensions?
  postgresql_version >= 90200
end

#supports_foreign_keys? ⇒ Boolean

Returns:

  • (Boolean) 


224
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 224

def supports_foreign_keys?; true end

#supports_hex_escaped_bytea? ⇒ Boolean

Returns:

  • (Boolean) 


246
247
248
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 246

def supports_hex_escaped_bytea?
  postgresql_version >= 90000
end

#supports_index_sort_order? ⇒ Boolean

Returns:

  • (Boolean) 


226
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 226

def supports_index_sort_order?; true end

#supports_insert_with_returning? ⇒ Boolean

Returns:

  • (Boolean) 


250
251
252
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 250

def supports_insert_with_returning?
  postgresql_version >= 80200
end

#supports_migrations? ⇒ Boolean

Returns:

  • (Boolean) 


228
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 228

def supports_migrations?; true end

#supports_partial_index? ⇒ Boolean

Returns:

  • (Boolean) 


230
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 230

def supports_partial_index?; true end

#supports_primary_key? ⇒ Boolean

Supports finding primary key on non-Active Record tables

Returns:

  • (Boolean) 


232
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 232

def supports_primary_key?; true end

#supports_ranges? ⇒ Boolean

Range data-types weren't introduced until PostgreSQL 9.2.

Returns:

  • (Boolean) 


255
256
257
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 255

def supports_ranges?
  postgresql_version >= 90200
end

#supports_savepoints? ⇒ Boolean

Returns:

  • (Boolean) 


234
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 234

def supports_savepoints?; true end

#supports_standard_conforming_strings? ⇒ Boolean

Does PostgreSQL support standard conforming strings?

Returns:

  • (Boolean) 


241
242
243
244
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 241

def supports_standard_conforming_strings?
  standard_conforming_strings?
  @standard_conforming_strings != :unsupported
end

#supports_transaction_isolation?(level = nil) ⇒ Boolean

Returns:

  • (Boolean) 


236
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 236

def supports_transaction_isolation?(level = nil); true end

#supports_views? ⇒ Boolean

Returns:

  • (Boolean) 


238
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 238

def supports_views?; true end

#truncate(table_name, name = nil) ⇒ Object 



479
480
481
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 479

def truncate(table_name, name = nil)
  execute "TRUNCATE TABLE #{quote_table_name(table_name)}", name
end

#use_insert_returning? ⇒ Boolean

Returns:

  • (Boolean) 


75
76
77
78
79
80
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 75

def use_insert_returning?
  if @use_insert_returning.nil?
    @use_insert_returning = supports_insert_with_returning?
  end
  @use_insert_returning
end

#valid_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


178
179
180
 
# File 'lib/arjdbc/postgresql/adapter.rb', line 178

def valid_type?(type)
  !native_database_types[type].nil?
end