From: phd at sun.med.ru (Oleg Broytmann)
Date: Sat, 3 Apr 1999 14:35:10 GMT
Subject: GadFly - MemoryError
Message-ID: <Pine.SOL2.3.96.SK.990403182611.18369K-100000@sun.med.ru>
Content-Length: 1025
X-UID: 817                                                  

Hello!

   I tried to add yeat another database backend to my project "Bookmarks
database". My database contains now about 3000 URLs, not too much, I think.
I subclass by BookmarksParser to parse bookmarks.html into gadfly database
and got a database of 500 Kbytes - very small database, I hope.
   Then I tried to find duplicates (there are duplicates). I ran the query:

SELECT b1.rec_no, b2.rec_no, b1.URL
   FROM bookmarks b1, bookmarks b2
WHERE b1.URL = b2.URL
AND   b1.rec_no < b2.rec_no

   GadFly eats all memory and fails with MemoryError. Is it that gadfly
really constructs multiplication of b1 and b2, thus getting 3000*3000
pairs? Or I just did something wrong?
   I tried to create indicies, but this was not of any help.

   BTW, where are indicies stored? After creating ones I didn't find
additional files - only one file in the database changed.

Oleg.
---- 
    Oleg Broytmann  National Research Surgery Centre  http://sun.med.ru/~phd/
           Programmers don't die, they just GOSUB without RETURN.





