Florian Weimer <[EMAIL PROTECTED]> writes:
> I run this innocent query
> CREATE TABLE foo AS SELECT DISTINCT bar FROM baz ORDER BY bar;
> and the resulting table contains duplicate rows. 8-(
> According to EXPLAIN, an index scan on the bar column is used (using
> the underlying B-tree index).
Do you mean an indexscan followed immediately by a Unique node? If
so, yeah, that would depend entirely on correct ordering of the
indexscan output to produce distinct results.
> If I drop the DISTINCT, the output is not correctly ordered, either.
> Perhaps this is an index corruption issue? The hardware itself seems
> fine.
Perhaps. Do you want to save off a physical copy of the index and then
try REINDEXing? If that fixes it, I'd be interested to compare the two
versions of the index.
regards, tom lane
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