>Hi I am upgrading a system originaly written in Fox 2.2 (I think it was 2.2) for DOS. I'm converting it into Vis Fox 6. Some of the index tags in the tables use character prime key fields and do this with DATE fields.
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>'primekeycharacterfield' + STR(999999-(AS_DATE-{01/01/1900}),6)
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>I figure that subtracting {01/01/1900} from the date and then subtracting from 999999 will give descending values. The later the date the higher the value.
>I'm wondering why the didn't just create a descending index.
>It wouldn't make a difference whether the prime key values were in ascending or descending order, it's only the dates that matter.
>Could you not create descending indexes in Fox for dos?
Yes, you could. But descending indices are not used, e.g., by Rushmore Optimization. So, many developers prefer to use only ascending indices, and open them in descending order, when required.
Also, this particular programmer perhaps did want to have the first field in ascending order, and the second, in descending order.
Hilmar.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
