DBSequence — PyBSDDB 6.2.7 documentation

# DBSequence

Read Oracle documentation for better understanding.

Sequences provide an arbitrary number of persistent objects that return an increasing or decreasing sequence of integers. Opening a sequence handle associates it with a record in a database. The handle can maintain a cache of values from the database so that a database update is not needed as the application allocates a value.

More info…

## DBSequence Methods

`DBSequence`(db, flags=0)

  Constructor. More info…

`open`(key, txn=None, flags=0)

  Opens the sequence represented by the key. More info…

`close`(flags=0)

  Close a DBSequence handle. More info…

`initial_value`(value)

  Set the initial value for a sequence. This call is only effective when the sequence is being created. More info…

`get`(delta=1, txn=None, flags=0)

  Returns the next available element in the sequence and changes the sequence value by delta. More info…

`get_dbp`()

  Returns the DB object associated to the DBSequence. More info…

`get_key`()

  Returns the key for the sequence. More info…

`remove`(txn=None, flags=0)

  Removes the sequence from the database. This method should not be called if there are other open handles on this sequence. More info…

`get_cachesize`()

  Returns the current cache size. More info…

`set_cachesize`(size)

  Configure the number of elements cached by a sequence handle. More info…

`get_flags`()

  Returns the current flags. More info…

`set_flags`(flags)

  Configure a sequence. More info…

`stat`(flags=0)

  Returns a dictionary of sequence statistics with the following keys:

  > wait | The number of times a thread of control was forced to wait on the handle mutex.
  > nowait | The number of times that a thread of control was able to obtain handle mutex without waiting.
  > current | The current value of the sequence in the database.
  > value | The current cached value of the sequence.
  > last_value | The last cached value of the sequence.
  > min | The minimum permitted value of the sequence.
  > max | The maximum permitted value of the sequence.
  > cache_size | The number of values that will be cached in this handle.
  > flags | The flags value for the sequence.

  More info…

`stat_print`(flags=0)

  Prints diagnostic information. More info…

`get_range`()

  Returns a tuple representing the range of values in the sequence. More info…

`set_range`((min, max))

  Configure a sequence range. More info…