FINDSET REPEAT UNTIL

Angelo
Angelo Member Posts: 180
in NAV/Navision Classic Client
Hi All,

Previously, I've got issue after looping, not all my records are modified as I forgot to use second table variable after reading topic FINDSET on other forum. However, I saw there are 2 approaches as the following:

Rec1.SETRANGE(Field1,Value1);
IF Rec1.FINDSET THEN
REPEAT
Rec2.GET(Rec1.PrimaryKey);
Rec2.Field1 = Value2;
Rec2.MODIFY;
UNTIL Rec1.NEXT = 0

Rec1.SETRANGE(Field1,Value1);
IF Rec1.FINDSET THEN
REPEAT
Rec2 := Rec1
Rec2.Field1 = Value2;
Rec2.MODIFY;
UNTIL Rec1.NEXT = 0

are both do the same thing? are both guarantee that modify will be successful 100%?
Which one is the best?



Answers

  • Juhl
    Juhl Member Posts: 724
    No need for 2 records variables.
    Just modify the field.
    You can also use modifyall
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  • Juhl
    Juhl Member Posts: 724
    Rec1.SETRANGE(Field1,Value1);
    Rec1.MODIFYALL(Field1,Value2,FALSE);
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  • Slawek_Guzek
    Slawek_Guzek Member Posts: 1,690
    The fastest is to use MODIFYALL as Juhl suggested.

    Among the two you have proposed the second one would be probably just a tad bit faster, I guess. The first one includes GET, which is, in theory, a relatively slow database access operation, but since you're GETting a record which has just been retrieved from the database it will be almost certainly fetched from the local cache.

    On the other hand, if you want to stick to looping and MODIFY, rather than using MODIFYALL (although looking at the sample you've posted I can's see any reason why you would not want to use MODIFYALL), each time you have to modify a field which is also used in SETRANGE or SETCURRENTKEY commands do keep using two records
    Slawek Guzek
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  • Angelo
    Angelo Member Posts: 180
    Hi All,

    My concern now is not about the performance but it's about modify record successfully.

    I mentioned that some records were not modified :( ,so that I try to change my code by using both approaches (use second variable). I hope MODIFYALL also give a guarantee 100% my record is modified perfectly.
  • TallyHo
    TallyHo Member Posts: 417
    edited 2019-04-19
    Probably you were modifying something that was affecting your loop. Modifyall does not have that problem, there is no loop.
  • RockWithNAV
    RockWithNAV Member Posts: 1,172
    @Slawek_Guzek - MODIFYALL is fastest to use if you are just modifying one record value but if you have multiple modifications then REPEAT UNTIL works faster then MODIFYALL.
    Thanks

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  • Angelo
    Angelo Member Posts: 180
    Thanks everybody for the answer, so far my problem run smoothly by using Option 2
  • swpolo
    swpolo Member Posts: 80
    Also it is useful to use options in findset to speed up execution.
    FINDSET(TRUE,FALSE) in your case.
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