Re: 5 new entries for FAQ - Mailing list pgsql-general

From Dan Armbrust
Subject Re: 5 new entries for FAQ
Date
Msg-id 42FA640B.3070209@gmail.com
Whole thread Raw
In response to Re: 5 new entries for FAQ  (Bruce Momjian <pgman@candle.pha.pa.us>)
Responses Re: 5 new entries for FAQ  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-general
Bruce Momjian wrote: <blockquote cite="mid200508101933.j7AJXGU12502@candle.pha.pa.us" type="cite"><br /><pre wrap="">
I have updated the FAQ to handle three of the items you mentioned.  In
one case, I added a new FAQ entry (double-quoting identifiers with a
link to our docs), and in two other cases (indexing long columns,
case-insensitive columns) I added to existing FAQ items where
appropriate.  Patch attached and applied.

For the batch job and single-CPU issues, they did not fit into existing
FAQ entries, and I am not sure they are asked enough to be added as
FAQs.  I am interested to hear other's opinions on this. </pre></blockquote><blockquote type="cite"><pre
wrap="">***************
*** 613,618 ****
--- 617,628 ----     <P>The maximum table size and maximum number of columns can be     quadrupled by increasing
thedefault block size to 32k.</P> 
 
+     <P>One limitation is that indexes can not be created on columns
+     longer than about 2,000 characters. Fortunately, such indexes are
+     rarely needed. Uniqueness is best guaranteed using another column
+     that is an MD5 hash of the long column, and full text indexing
+     allows for searching of words within the column.</P>
+      <H3><A name="4.5">4.5</A>) How much database disk space is required     to store data from a
typicaltext file?</H3></pre></blockquote><blockquote cite="mid200508101933.j7AJXGU12502@candle.pha.pa.us"
type="cite"><prewrap=""><hr size="4" width="90%" /> </pre></blockquote> I liked the FAQ entry written up by the
originalsubmitter much better, WRT to the long index issue.  This write up does not contain the actual error message
encountered,so its not going to be found by someone looking for a solution to the problem.  It doesn't contain the
optionalworkaround, and it doesn't have a link into the full text searching features as the recommended fix.  I was one
ofthe more recent people to encounter this problem, and I don't think that this FAQ would have helped me (if I even saw
it,because google certainly won't pick it up in a way that most people will search when the encounter the issue - they
aregoing to put in the error message)<br /><br /> Dan<br /><pre class="moz-signature" cols="72">-- 
 
****************************
Daniel Armbrust
Biomedical Informatics
Mayo Clinic Rochester
daniel.armbrust(at)mayo.edu
<a class="moz-txt-link-freetext" href="http://informatics.mayo.edu/">http://informatics.mayo.edu/</a>
</pre>

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