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.

Defined Under Namespace

Classes: ArjdbcTypeMapInitializer

Constant Summary collapse

ADAPTER_NAME =
'PostgreSQL'.freeze
NATIVE_DATABASE_TYPES =
{
  primary_key:  'bigserial 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' },
  oid:          { name: 'oid' },
  path:         { name: 'path' },
  point:        { name: 'point' },
  polygon:      { name: 'polygon' },
  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_classObject



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

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

Instance Method Details

#adapter_nameObject



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

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.



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# File 'lib/arjdbc/postgresql/adapter.rb', line 449

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_schemasObject



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# File 'lib/arjdbc/postgresql/adapter.rb', line 425

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



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# File 'lib/arjdbc/postgresql/adapter.rb', line 401

def clear_cache!
  super
  # Make sure all query plans are *really* gone
  @connection.execute 'DEALLOCATE ALL' if active?
end

#client_min_messagesObject

Returns the current client message level.



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# File 'lib/arjdbc/postgresql/adapter.rb', line 430

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.



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# File 'lib/arjdbc/postgresql/adapter.rb', line 437

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_connectionObject

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.



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# File 'lib/arjdbc/postgresql/adapter.rb', line 112

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

#default_index_type?(index) ⇒ Boolean

From AR 5.1 postgres_adapter.rb

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 300

def default_index_type?(index) # :nodoc:
  index.using == :btree || super
end

#default_sequence_name(table_name, pk = "id") ⇒ Object

:nodoc:



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# File 'lib/arjdbc/postgresql/adapter.rb', line 415

def default_sequence_name(table_name, pk = "id") #:nodoc:
  serial_sequence(table_name, pk)
rescue ActiveRecord::StatementInvalid
  %Q("#{table_name}_#{pk}_seq")
end

#disable_extension(name) ⇒ Object



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# File 'lib/arjdbc/postgresql/adapter.rb', line 308

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

#enable_extension(name) ⇒ Object



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# File 'lib/arjdbc/postgresql/adapter.rb', line 304

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

#escape_bytea(string) ⇒ Object

Note:

quote_string implemented as native



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# File 'lib/arjdbc/postgresql/adapter.rb', line 461

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



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

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



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# File 'lib/arjdbc/postgresql/adapter.rb', line 376

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)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 312

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

#extensionsObject



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# File 'lib/arjdbc/postgresql/adapter.rb', line 320

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



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# File 'lib/arjdbc/postgresql/adapter.rb', line 340

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_algorithmsObject



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# File 'lib/arjdbc/postgresql/adapter.rb', line 329

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

#jdbc_column_classObject



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# File 'lib/arjdbc/postgresql/adapter.rb', line 45

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

#last_insert_id_result(sequence_name) ⇒ Object



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# File 'lib/arjdbc/postgresql/adapter.rb', line 421

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

#max_identifier_lengthObject Also known as: table_alias_length, index_name_length

Returns the max identifier length supported by PostgreSQL



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# File 'lib/arjdbc/postgresql/adapter.rb', line 356

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

#native_database_typesObject



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# File 'lib/arjdbc/postgresql/adapter.rb', line 196

def native_database_types
  NATIVE_DATABASE_TYPES
end

#postgresql_versionObject

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



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# File 'lib/arjdbc/postgresql/adapter.rb', line 54

def postgresql_version
  @postgresql_version ||=
    begin
      version = @connection.database_product
      if match = version.match(/([\d\.]*\d).*?/)
        version = match[1].split('.').map(&:to_i)
        # PostgreSQL version representation does not have more than 4 digits
        # From version 10 onwards, PG has changed its versioning policy to
        # limit it to only 2 digits. i.e. in 10.x, 10 being the major
        # version and x representing the patch release
        # Refer to:
        #   https://www.postgresql.org/support/versioning/
        #   https://www.postgresql.org/docs/10/static/libpq-status.html -> PQserverVersion()
        # for more info

        if version.size >= 3
          (version[0] * 100 + version[1]) * 100 + version[2]
        elsif version.size == 2
          if version[0] >= 10
            version[0] * 100 * 100 + version[1]
          else
            (version[0] * 100 + version[1]) * 100
          end
        elsif version.size == 1
          version[0] * 100 * 100
        else
          0
        end
      else
        0
      end
    end
end

#quote_table_name(name) ⇒ Object



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# File 'lib/arjdbc/postgresql/adapter.rb', line 473

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



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# File 'lib/arjdbc/postgresql/adapter.rb', line 348

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



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# File 'lib/arjdbc/postgresql/adapter.rb', line 488

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

#reset!Object



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# File 'lib/arjdbc/postgresql/adapter.rb', line 407

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.



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# File 'lib/arjdbc/postgresql/adapter.rb', line 334

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

#set_client_encoding(encoding) ⇒ Object



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# File 'lib/arjdbc/postgresql/adapter.rb', line 105

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_stringsObject

Enable standard-conforming strings if available.



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# File 'lib/arjdbc/postgresql/adapter.rb', line 205

def set_standard_conforming_strings
  self.standard_conforming_strings=(true)
end

#standard_conforming_strings=(enable) ⇒ Object

Enable standard-conforming strings if available.



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# File 'lib/arjdbc/postgresql/adapter.rb', line 210

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)


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

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_advisory_locks?Boolean

Returns:

  • (Boolean)


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

def supports_advisory_locks?; true end

#supports_comments?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 262

def supports_comments?; true end

#supports_datetime_with_precision?Boolean

Returns:

  • (Boolean)


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

def supports_datetime_with_precision?; true end

#supports_ddl_transactions?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 240

def supports_ddl_transactions?; true end

#supports_explain?Boolean

Returns:

  • (Boolean)


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

def supports_explain?; true end

#supports_expression_index?Boolean

Returns:

  • (Boolean)


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

def supports_expression_index?; true end

#supports_extensions?Boolean

Returns:

  • (Boolean)


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

def supports_extensions?
  postgresql_version >= 90200
end

#supports_foreign_keys?Boolean

Returns:

  • (Boolean)


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

def supports_foreign_keys?; true end

#supports_hex_escaped_bytea?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 270

def supports_hex_escaped_bytea?
  postgresql_version >= 90000
end

#supports_index_sort_order?Boolean

Returns:

  • (Boolean)


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

def supports_index_sort_order?; true end

#supports_insert_with_returning?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 282

def supports_insert_with_returning?
  postgresql_version >= 80200
end

#supports_json?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 278

def supports_json?
  postgresql_version >= 90200
end

#supports_materialized_views?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 274

def supports_materialized_views?
  postgresql_version >= 90300
end

#supports_partial_index?Boolean

Returns:

  • (Boolean)


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

def supports_partial_index?; true end

#supports_pgcrypto_uuid?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 286

def supports_pgcrypto_uuid?
  postgresql_version >= 90400
end

#supports_ranges?Boolean

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

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 291

def supports_ranges?
  postgresql_version >= 90200
end

#supports_savepoints?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 254

def supports_savepoints?; true end

#supports_standard_conforming_strings?Boolean

Does PostgreSQL support standard conforming strings?

Returns:

  • (Boolean)


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

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

#supports_transaction_isolation?Boolean

Returns:

  • (Boolean)


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

def supports_transaction_isolation?; true end

#supports_views?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 258

def supports_views?; true end

#truncate(table_name, name = nil) ⇒ Object



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# File 'lib/arjdbc/postgresql/adapter.rb', line 527

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

#use_insert_returning?Boolean

Returns:

  • (Boolean)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 98

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)


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# File 'lib/arjdbc/postgresql/adapter.rb', line 200

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