Re: RPGLESQL - random records from large file

A large file,say a million records in which there are about 12,000
records with a "W" in Field20. I want 10 random records from the
12000. I can't figure out how to write the WHERE clause so that only
records from the 12,000 will be included .

Here's what I use for random hits on the big file:

exec sql select rand(MICROSECOND(CURRENT_TIMESTAMP)) into :wField5
from SYSIBM/SYSDUMMY1;
wSeed = wField5 * 10000;
//
---------------------------------------------------------------------
// Get 10 random numbers
clear wCount;
wNdx = 0;
dow wNdx < 10 and wCount < 1200; // (if we can't get 10 in
1200, bail)
wCount += 1;
exec sql select rand(:wSeed) into :wField5
from SYSIBM/SYSDUMMY1;
wSeed = wField5 * 10000;
exec sql select FIELD1 into :wField1
from FILE01
where rrn(FILE01) = :wSeed;

...

"where rrn(FILE01) = :wSeed and FIELD20 = 'W';" seems easy but somehow
wrong.

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