MTRETAIN=Y|N determines whether the allocated rows and index areas are to be retained when an MT command is issued or whether they are to be reduced to the original allocation before table expansion. The default is “N”, which is current processing—not retained.
Also see ZEROROWS—Zero Data Table Rows on De-allocation.
This option applies to the TSR created by this region/job and all users accessing it (applies only to Release 6.0.3 and above).
This option can be specified for all tableBASE interfaces.