Re: Index usage when bitwise operator is used

Hi,

A little clarification. Actually, TBL1.CATEGORY and/or TBL2.CATEGORY may
hold a binary value having multiple binary(ies) '1'.
Each binary value column represent an business attribute.
If a binary value column is equal to '1', it means that the business
attribute is True,
otherwise it is false.
I adopted this avoid defining a detail table to table TBL1. Idem to TBL2.

If TBL1.CATEGORY | TBL2.CATEGORY > 0
=> it means that we have at least one common business attribute that is TRUE
for TBL1 and TBL2.

Regards
W.Alf

On 9/17/07, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov> writes:
> > On Mon, Sep 17, 2007 at 2:49 AM, in message
> > <1190015368(dot)148293(dot)56830(at)y42g2000hsy(dot)googlegroups(dot)com>, valgog
> > <valgog(at)gmail(dot)com> wrote:=20
> >> Are you sure you understood what was the question?
> >>
> >> Is the TBL1.CATEGORY = TBL2.CATEGORY the same as TBL1.CATEGORY &
> >> TBL2.CATEGORY > 0?
>
> > Yes, given that he stipulated that one and only one bit would be set.
>
> Really? In that case, isn't this bit-field just a bad implementation of
> an enum-style field?
>
> regards, tom lane
>
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