Hi!

Sorry for delay, I hadn't access to Internet.

> [3]
> Again, in g_int_decompress(), I couldn't figure out the functionality of
> below lines:

gist__int_ops use rangeset compression technique, read about in "THE RD-TREE: AN INDEX STRUCTURE FOR SETS", Joseph M. Hellerstein,
http://www.sai.msu.su/~megera/postgres/gist/papers/rd-tree.ps


About your patches:
* intarray_contains.patch.0 - applied

* intarray_union.patch.0 - doesn't applied, but make small optimization to reduce number non-unique values. I don't believe that one pass through array with a lot of ifs will be faster than two pass with simple ifs. Did you some tests?

* intarray_same.patch.0 - move SORT as you suggest, but don't touch algorithm.
 1) if (A[0] == B[0] && A[1] == B[1] && ...)

 2) if (A[0] == B[0] && A[  N] == B[  N] &&
    A[1] == B[1] && A[N-1] == B[N-1] &&
    ...)

Why are you sure that second a much faster? Did you make tests? Number of comparisons is the same...

* intarray_sort.patch.0 - doesn't applied. isort() is very often called for already sorted and unique arrays (which comes from index), so it should be fast as possible for sorted arrays. As I remember ordered array is a worst case for qsort(). May be, it will be better choice to use mergesort.




--
Teodor Sigaev                                   E-mail: [EMAIL PROTECTED]
                                                   WWW: http://www.sigaev.ru/

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