class ActiveRecord::ConnectionAdapters::NullPool

:nodoc:

def async_executor; end 

def async_executor; end

def checkin(_); end 

def checkin(_); end

def connection_descriptor; end 

def connection_descriptor; end

def db_config 

def db_config
  NULL_CONFIG
end

def dirties_query_cache 

def dirties_query_cache
  true
end

def initialize 

def initialize
  super()
  @mutex = Mutex.new
  @server_version = nil
end

def remove(_); end 

def remove(_); end

def schema_cache; end 

def schema_cache; end

def schema_reflection 

def schema_reflection
  SchemaReflection.new(nil)
end

def server_version(connection) # :nodoc:

:nodoc: 
def server_version(connection) # :nodoc:
  @server_version || @mutex.synchronize { @server_version ||= connection.get_database_version }
end