John, If this is an opportunity to "fix" something that already exists, then this may not be a solution for you. On the other hand, if this is something the programmer is working on tight now, that is, in development, consider this.
What if you removed the AIX option from the problem completely. Define a second KSDS file and then, in the program, if the key is not null, whatever one wants to define as null, then insert the key of the primary record into the alternate index KSDS file. Now you have an optional manual connection between the primary record and an alternate index. If you want/need to, you could even define this "access method" as something performed by a "black box" routine and have all access to the primary record be via a "black box". Doing that would allow the definition of "null" to change as needed. Maybe today null means any record with binary zeroes in the key, but tomorrow it may be all primary records with the value of "sasquatch" in the primary key field. You may also find, down the road, that another alternate index is desired with the same attributes of many null keys and not wanting them in the AIX file so you add it to the "black box" and life goes on. Chuck -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of John McKown Sent: Monday, May 04, 2009 10:37 AM To: [email protected] Subject: Crazy VSAM question A programmer has posed this question to me. My response, so far, has been "no way". But I'll ask the truly knowledgeable here. We have a KSDS with an AIX. The data in the field which defines the alternate keys is sometimes "unknown" and coded as LOW-VALUES (0x00's). Well, this has lead to a problem where the number of base records for the "unknown" value is often quite huge and exceeds the maximum allowable record size on the AIX. This causes the base record add or update to fail. What the programmer wants is a way to tell VSAM that if the AIX key is 0x00s, that it is not necessary to update the AIX at all. I cannot think of any way to do this. Any clever ideas? -- John ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
