Modifying Physical Database Definitions › Changing the Access Method of a File › Step 1: Expand the Page Size

Step 1: Expand the Page Size

Converting from Non-VSAM to VSAM

When you convert a non-VSAM file to VSAM, expand the area's page size first if the page size of the area is significantly smaller than the size of the VSAM control interval. The optimal page size is 8 bytes less than the VSAM control interval.

Converting from VSAM to non-VSAM

When you convert a VSAM file to non-VSAM, consider expanding the area's page size either before or after the conversion if the page size of the area is inefficient for the device type.

Note:

• For optimal page sizes based on device type, see the CA IDMS Database Design Guide.
• For the steps involved in expanding the page size of an area, see 27.5.1, "Increasing the Page Size of an Area".