Class: ActiveRecord::ConnectionAdapters::RedshiftAdapter

Inherits:
PostgreSQLAdapter
  • Object
show all
Defined in:
lib/active_record/connection_adapters/redshift_adapter.rb

Constant Summary collapse

ADAPTER_NAME = 
'Redshift'.freeze
NATIVE_DATABASE_TYPES = 
PostgreSQLAdapter::NATIVE_DATABASE_TYPES.merge({
  primary_key: "bigint primary key identity(1,1)",
})

Instance Method Summary collapse

Constructor Details

#initialize(connection, logger, connection_parameters, config) ⇒ RedshiftAdapter

Returns a new instance of RedshiftAdapter.



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 37

def initialize(connection, logger, connection_parameters, config)
  super
end

Instance Method Details

#column_definitions(table_name) ⇒ Object

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



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 142

def column_definitions(table_name) #:nodoc:
  exec_query(<<-end_sql, 'SCHEMA').rows
    SELECT a.attname, format_type(a.atttypid, a.atttypmod),
             pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod
      FROM pg_attribute a LEFT JOIN pg_attrdef d
        ON a.attrelid = d.adrelid AND a.attnum = d.adnum
     WHERE a.attrelid = '#{quote_table_name(table_name)}'::regclass
       AND a.attnum > 0 AND NOT a.attisdropped
     ORDER BY a.attnum
  end_sql
end

#configure_connection ⇒ Object

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



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 43

def configure_connection
  if @config[:encoding]
    @connection.set_client_encoding(@config[: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 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 @local_tz
  #   execute("SET time zone '#{@local_tz}'", 'SCHEMA')
  # end

  # SET statements from :variables config hash
  # http://www.postgresql.org/docs/8.3/static/sql-set.html
  variables = @config[:variables] || {}
  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

#create_table_definition(*args) ⇒ Object

Schema Statements



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 180

def create_table_definition(*args) # :nodoc:
  Redshift::TableDefinition.new(*args)
end

#get_advisory_lock(lock_id) ⇒ Object 



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 172

def get_advisory_lock(lock_id)
  lock_id
end

#indexes(table_name, name = nil) ⇒ Object 



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 168

def indexes(table_name, name = nil)
  []
end

#native_database_types ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 80

def native_database_types #:nodoc:
  NATIVE_DATABASE_TYPES
end

#postgresql_version ⇒ Object 



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 75

def postgresql_version
  # Hack to avoid native PostgreQLAdapter's version check
  return 100000 + 80002
end

#primary_keys(table) ⇒ Object

Returns just a table’s primary key



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 155

def primary_keys(table)
  row = exec_query(<<-end_sql, 'SCHEMA').rows.map do |row|
    SELECT DISTINCT(attr.attname)
    FROM pg_attribute attr
    INNER JOIN pg_depend dep ON attr.attrelid = dep.refobjid AND attr.attnum = dep.refobjsubid
    INNER JOIN pg_constraint cons ON attr.attrelid = cons.conrelid AND attr.attnum = cons.conkey[1]
    WHERE cons.contype = 'p'
      AND dep.refobjid = '#{quote_table_name(table)}'::regclass
  end_sql
    row && row.first
  end
end

#release_advisory_lock(lock_id) ⇒ Object 



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 176

def release_advisory_lock(lock_id)
end

#schema_creation ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 188

def schema_creation # :nodoc:
  Redshift::SchemaCreation.new self
end

#supports_extensions? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 108

def supports_extensions?
  false
end

#supports_foreign_keys? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 100

def supports_foreign_keys?
  false
end

#supports_index_sort_order? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 88

def supports_index_sort_order?
  false
end

#supports_materialized_views? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 116

def supports_materialized_views?
  false
end

#supports_partial_index? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 92

def supports_partial_index?
  false
end

#supports_ranges? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 112

def supports_ranges?
  false
end

#supports_statement_cache? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 84

def supports_statement_cache?
  false
end

#supports_transaction_isolation? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 96

def supports_transaction_isolation?
  false
end

#supports_views? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 104

def supports_views?
  false
end

#update_table_definition(table_name, base) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 184

def update_table_definition(table_name, base) #:nodoc:
  Redshift::Table.new(table_name, base)
end

#use_insert_returning? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/redshift_adapter.rb', line 120

def use_insert_returning?
  false
end