Class: BigRecord::ConnectionAdapters::AbstractAdapter

Inherits:
Object
  • Object
show all
Includes:
DatabaseStatements, Quoting
Defined in:
lib/big_record/connection_adapters/abstract_adapter.rb

Overview

All the concrete database adapters follow the interface laid down in this class. You can use this interface directly by borrowing the database connection from the Base with Base.connection.

Most of the methods in the adapter are useful during migrations. Most notably, SchemaStatements#create_table, SchemaStatements#drop_table, SchemaStatements#add_index, SchemaStatements#remove_index, SchemaStatements#add_column, SchemaStatements#change_column and SchemaStatements#remove_column are very useful.

Direct Known Subclasses

CassandraAdapter, HbaseAdapter, HbaseRestAdapter

Constant Summary

@@row_even = 
true

Instance Method Summary

Methods included from Quoting

#quote, #quote_column_name, #quote_string, #quoted_date, #quoted_false, #quoted_true

Methods included from DatabaseStatements

#insert_fixture

Constructor Details

- (AbstractAdapter) initialize(connection, logger = nil)

:nodoc: 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 21

def initialize(connection, logger = nil) #:nodoc:
  @connection, @logger = connection, logger
  @runtime = 0
  @last_verification = 0
end

Instance Method Details

- (Boolean) active?

Is this connection active and ready to perform queries?

Returns:

  • (Boolean) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 79

def active?
  @active != false
end

- (Object) adapter_name

Returns the human-readable name of the adapter. Use mixed case - one can always use downcase if needed. 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 29

def adapter_name
  'Abstract'
end

- (Object) create_table(table_name, column_families)

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 164

def create_table(table_name, column_families)
  raise NotImplementedError
end

- (Object) delete(table_name, row)

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 150

def delete(table_name, row)
  raise NotImplementedError
end

- (Object) delete_all(table_name)

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 154

def delete_all(table_name)
  raise NotImplementedError
end

- (Object) disable_referential_integrity(&block)

Override to turn off referential integrity while executing &block 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 72

def disable_referential_integrity(&block)
  yield
end

- (Object) disconnect!

Close this connection 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 89

def disconnect!
  @active = false
end

- (Object) drop_table(table_name)

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 168

def drop_table(table_name)
  raise NotImplementedError
end

- (Object) get(table_name, row, column, options = {})

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 130

def get(table_name, row, column, options={})
  raise NotImplementedError
end

- (Object) get_columns(table_name, row, columns, options = {})

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 138

def get_columns(table_name, row, columns, options={})
  raise NotImplementedError
end

- (Object) get_columns_raw(table_name, row, columns, options = {})

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 134

def get_columns_raw(table_name, row, columns, options={})
  raise NotImplementedError
end

- (Object) get_consecutive_rows(table_name, start_row, limit, columns, stop_row = nil)

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 146

def get_consecutive_rows(table_name, start_row, limit, columns, stop_row = nil)
  raise NotImplementedError
end

- (Object) get_consecutive_rows_raw(table_name, start_row, limit, columns, stop_row = nil)

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 142

def get_consecutive_rows_raw(table_name, start_row, limit, columns, stop_row = nil)
  raise NotImplementedError
end

- (Object) get_raw(table_name, row, column, options = {})

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 126

def get_raw(table_name, row, column, options={})
  raise NotImplementedError
end

- (Boolean) prefetch_primary_key?(table_name = nil)

Should primary key values be selected from their corresponding sequence before the insert statement? If true, next_sequence_value is called before each insert to set the record’s primary key. This is false for all adapters but Firebird.

Returns:

  • (Boolean) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 53

def prefetch_primary_key?(table_name = nil)
  false
end

- (Object) quote_table_name(name)

Override to return the quoted table name if the database needs it 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 65

def quote_table_name(name)
  name
end

- (Object) raw_connection

Provides access to the underlying database connection. Useful for when you need to call a proprietary method such as postgresql’s lo_* methods 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 112

def raw_connection
  @connection
end

- (Object) reconnect!

Close this connection and open a new one in its place. 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 84

def reconnect!
  @active = true
end

- (Boolean) requires_reloading?

Returns true if its safe to reload the connection between requests for development mode. This is not the case for Ruby/MySQL and it’s not necessary for any adapters except SQLite.

Returns:

  • (Boolean) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 95

def requires_reloading?
  false
end

- (Object) reset_runtime

:nodoc: 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 57

def reset_runtime 
  rt, @runtime = @runtime, 0
  rt
end

- (Boolean) supports_count_distinct?

Does this adapter support using DISTINCT within COUNT? This is true for all adapters except sqlite.

Returns:

  • (Boolean) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 41

def supports_count_distinct?
  false
end

- (Boolean) supports_ddl_transactions?

Returns:

  • (Boolean) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 45

def supports_ddl_transactions?
  false
end

- (Boolean) supports_migrations?

Does this adapter support migrations? Backend specific, as the abstract adapter always returns false.

Returns:

  • (Boolean) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 35

def supports_migrations?
  false
end

- (Boolean) table_exists?(table_name)

SCHEMA STATEMENTS ========================================

Returns:

  • (Boolean)

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 160

def table_exists?(table_name)
  raise NotImplementedError
end

- (Object) update(table_name, row, values, timestamp)

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 122

def update(table_name, row, values, timestamp)
  raise NotImplementedError
end

- (Object) update_raw(table_name, row, values, timestamp)

DATABASE STATEMENTS ======================================

Raises:

  • (NotImplementedError) 


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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 118

def update_raw(table_name, row, values, timestamp)
  raise NotImplementedError
end

- (Object) verify!(timeout)

Lazily verify this connection, calling active? only if it hasn’t been called for timeout seconds. 



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# File 'lib/big_record/connection_adapters/abstract_adapter.rb', line 101

def verify!(timeout)
  now = Time.now.to_i
  if (now - @last_verification) > timeout
    reconnect! unless active?
    @last_verification = now
  end
end