[thelist] MySQL GROUP BY Anomaly?
Jay Blanchard
jay.blanchard at niicommunications.com
Thu May 9 12:51:01 CDT 2002
I have 2 tables with RecordDate in them, one has millions of records, one
has hundreds of records. If I perform the following query on the table with
hundreds;
mysql> select RecordDate
-> from tblInfo
-> WHERE RecordDate BETWEEN '2002-03-04' AND '2002-03-06'
-> GROUP BY RecordDate;
I get three rows back in the result;
+------------+
| RecordDate |
+------------+
| 2002-03-04 |
| 2002-03-05 |
| 2002-03-06 |
+------------+
but if I run this query against the table with millions of records I get (a
small snippet of the results)
| 2002-03-06 |
| 2002-03-05 |
| 2002-03-06 |
| 2002-03-05 |
| 2002-03-06 |
| 2002-03-05 |
| 2002-03-06 |
| 2002-03-05 |
| 2002-03-04 |
+------------+
34164 rows in set (17.78 sec)
Can anyone enlighten me as to what is happening? Both tables are on the same
machine, but the one with millions of records is a MERGE table. If I run the
query against the individual tables in the merge, they return the proper (3
row) result.
Thanks!
Jay
More information about the thelist
mailing list