defragdb

Name

defragdb — Pack (defragment) database

Synopsis

call defragdb(handle,verbose,status)
integer*4 handle
integer* verbose
integer*4 status

Description

defragdb packs the database handle. All inactive and/or deleted sets are removed, as well as any empty space. Note that defragdb modifies the file offset (also referred to as file address) of the datasets. If no empty space is found defragdb does not modify the database.

Parameters

handle: Database handle (input). The file handle handle may not exceed the maximum number of simultaneously open databases.
verbose: Verbose flag (input). Dummy argument for compatibility with version 6.
status: Status code returned (output). Upon successful completion of the operation, the status value 0 is returned. A negative value is returned, if an error has been detected. A positive value is returned, if a warning has been issued. See MemCom error codes.

Warning

In the current version of MemCom this function is still in an experimental state, i.e it is not completely safe: If, for some reason (power off, kill process, etc.) mcDBpack cannot terminate, some or all data are lost. If, for the time being, an absolutely safe operation is required, copy the entire file to a new file (note that this method requires up to twice the amount of disk space occupied by the current database).

defragdb changes the file addresses of the datasets. Thus, any function which makes use of such addresses (like when calling vdb file operations) must then be updated!