# MULTIFETCH Vs PREFETCH **URL:** \ **Category:** Forum\ **Tags:** Adabas-Natural, Natural, Natural-on-Mainframes\ **Created:** [December 2, 2009, 1:59am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273 "2009-12-02T01:59:18Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Michele1](https://avatars.discourse-cdn.com/v4/letter/m/e56c9b/32.png) [@Michele1](https://techcommunity.softwareag.com/u/Michele1)\ **Post date:** [December 2, 2009, 1:59am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/1 "2009-12-02T01:59:18Z")
I need to know the difference between Multifetch and Prefetch. I have read the documentation and I am confused. 1. Can I use MultiFetch in batch jobs running on Z/OS? 2. For Multifetch in batch jobs, do I need any special parameters in my JCL. 3. Which is more efficient Multifetch or PreFetch? 4. Can I use Multifetch in CICS online programs? 5. What is the difference between PREFETCH = YES and PREFETCH = OLD I coded a batch job and put in production. I used MultiFetch 10 on a read statement against a Adabas file. Here is the main loop: READ MULTI-FETCH 10 INS-UV1 BY INS-POLICY-EXP-DATE = #START-DATE IF INS-UV1.INS-POLICY-EXP-DATE \> #END-DATE ESCAPE BOTTOM /\* last rec for date range END-IF - ``` Ignore cancelled policy. ``` IF INS-UV1.INS-POLICY-CANCL-DATE \> 0 ESCAPE TOP END-IF RESET APPL-UV1 ENDRS-UV1 #APPL-FOUND #REPORT-PI #REPORT-INS #OUT-INSE-REC #ENDRS-KEY PERFORM FIND-APPLICATION IF #APPL-FOUND PERFORM FIND-ENDRS END-IF PERFORM WRITE-EXTRACT-RECORD END-READ /\* Ins-policy read - This seems to work, but I did not code in the JCL any PREFETCH Commands. Do I need them? Am i really doing a MULTIFETCH in this batch program or is it being ignored. Any help would be appreciated. THanks. 🙂 ---
**Author:** ![Ralph\_Zbrog](https://sea1.discourse-cdn.com/techcommunity/user_avatar/techcommunity.softwareag.com/ralph_zbrog/32/78_2.png) [@Ralph\_Zbrog](https://techcommunity.softwareag.com/u/Ralph_Zbrog)\ **Post date:** [December 2, 2009, 4:26am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/2 "2009-12-02T04:26:17Z")
PREFETCH is invoked via JCL. Multifetch may be invoked via JCL or at the statement level in Natural. > [@](#): > > Can I use MultiFetch in batch jobs running on Z/OS? Yes, of course. Via JCL or Natural statements. > [@](#): > > For Multifetch in batch jobs, do I need any special parameters in my JCL. Via JCL, you specify PREFETCH=YES. For statement-level Multi-fetch, this JCL parameter is not necessary. > [@](#): > > Which is more efficient Multifetch or PreFetch? Under zOS, Prefetch can perform better. > [@](#): > > Can I use Multifetch in CICS online programs? Yes, at the Natural statement level. > [@](#): > > What is the difference between PREFETCH = YES and PREFETCH = OLD PREFETCH=YES invokes (the newer) Multi-fetch; PREFETCH=OLD invokes (the older) PREFETCH. To verify that Multi-fetch is being applied (batch or on-line), issue the TEST DBLOG command before and after running/executing your program. Look at the OP column of the report. An M signifies a Multi-fetched/physical call; a \< signifies a logical call. ---
**Author:** ![Michele1](https://avatars.discourse-cdn.com/v4/letter/m/e56c9b/32.png) [@Michele1](https://techcommunity.softwareag.com/u/Michele1)\ **Post date:** [December 2, 2009, 4:51am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/3 "2009-12-02T04:51:08Z")
Ralph: Thank you for your prompt reply. Forgive me, how do I do a Test Dblog in batch. Is there a JCL statement? ---
**Author:** ![Ralph\_Zbrog](https://sea1.discourse-cdn.com/techcommunity/user_avatar/techcommunity.softwareag.com/ralph_zbrog/32/78_2.png) [@Ralph\_Zbrog](https://techcommunity.softwareag.com/u/Ralph_Zbrog)\ **Post date:** [December 2, 2009, 4:59am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/4 "2009-12-02T04:59:22Z")
```auto //CMSYNIN DD * LOGON natlib TEST DBLOG yourpgm TEST DBLOG FIN /* ``` ---
**Author:** ![Michele1](https://avatars.discourse-cdn.com/v4/letter/m/e56c9b/32.png) [@Michele1](https://techcommunity.softwareag.com/u/Michele1)\ **Post date:** [December 2, 2009, 5:08am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/5 "2009-12-02T05:08:37Z")
Ralph, that is magnificient, I will give it a try and learn more! THanks a whole bunch!..Michele 😃 ---
**Author:** ![Michele1](https://avatars.discourse-cdn.com/v4/letter/m/e56c9b/32.png) [@Michele1](https://techcommunity.softwareag.com/u/Michele1)\ **Post date:** [December 2, 2009, 5:46am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/6 "2009-12-02T05:46:30Z")
Ralph, another question: If I have MultiFetch (10) coded in a Batch program, and I have the PreFetch = OLD parameter in the JCL, which is used, Multifetch or Prefetch? What is the advantage of using Prefetch in Batch ? What is the advantage of using MultiFetch in Batch? We are using Z/OS. Thanks in advance. I did get my DBLOG, and now I will learn how to read it!..SMILE! ---
**Author:** ![Ralph\_Zbrog](https://sea1.discourse-cdn.com/techcommunity/user_avatar/techcommunity.softwareag.com/ralph_zbrog/32/78_2.png) [@Ralph\_Zbrog](https://techcommunity.softwareag.com/u/Ralph_Zbrog)\ **Post date:** [December 2, 2009, 7:00am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/7 "2009-12-02T07:00:49Z")
> [@](#): > > If I have MultiFetch (10) coded in a Batch program, and I have the PreFetch = OLD parameter in the JCL, which is used, Multifetch or Prefetch? I believe that the statement-level specification will override the batch specification. You can verify this with TEST DBLOG (and then report back to us). > [@](#): > > What is the advantage of using Prefetch in Batch ? > > What is the advantage of using MultiFetch in Batch? Both Prefetch and Multi-fetch are implementations of Adabas read-ahead processing. Adabas retrieves multiple records for each physical call, thereby reducing overhead. The end result for you is much shorter batch job elapsed times. ---
**Author:** ![Curtis\_Pew](https://avatars.discourse-cdn.com/v4/letter/c/5f9b8f/32.png) [@Curtis\_Pew](https://techcommunity.softwareag.com/u/Curtis_Pew)\ **Post date:** [December 3, 2009, 6:58pm UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/8 "2009-12-03T18:58:35Z")
> [@Ralph Zbrog](#): > > The end result for you is much shorter batch job elapsed times. The end result may be shorter batch job elapsed times. The “gotcha ---
**Author:** ![Steve\_Robinson](https://sea1.discourse-cdn.com/techcommunity/user_avatar/techcommunity.softwareag.com/steve_robinson/32/107_2.png) [@Steve\_Robinson](https://techcommunity.softwareag.com/u/Steve_Robinson)\ **Post date:** [December 4, 2009, 12:34am UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/9 "2009-12-04T00:34:46Z")
NOT STARTING FROM … ENDING AT NOT STARTING FROM… THRU Only STARTING FROM … TO works as Curtis stated. steve ---
**Author:** ![system](https://global.discourse-cdn.com/techcommunity/original/3X/c/d/cd19967bb605d28a72d77eb83a1cae22f3df2eb8.svg) [@system](https://techcommunity.softwareag.com/u/system)\ **Post date:** [April 2, 2021, 2:57pm UTC](https://techcommunity.softwareag.com/t/multifetch-vs-prefetch/92273/10 "2021-04-02T14:57:48Z")