Re: 5 new entries for FAQ

From: Dan Armbrust <daniel(dot)armbrust(dot)list(at)gmail(dot)com>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: 5 new entries for FAQ
Date: 2005-08-10 20:31:07
Message-ID: 42FA640B.3070209@gmail.com
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Bruce Momjian wrote:
<blockquote cite="mid200508101933(dot)j7AJXGU12502(at)candle(dot)pha(dot)pa(dot)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 ----
&lt;P&gt;The maximum table size and maximum number of columns can be
quadrupled by increasing the default block size to 32k.&lt;/P&gt;

+ &lt;P&gt;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.&lt;/P&gt;
+
&lt;H3&gt;&lt;A name="4.5"&gt;4.5&lt;/A&gt;) How much database disk space is required
to store data from a typical text file?&lt;/H3&gt;</pre>
</blockquote>
<blockquote cite="mid200508101933(dot)j7AJXGU12502(at)candle(dot)pha(dot)pa(dot)us"
type="cite">
<pre wrap=""><hr size="4" width="90%">
</pre>
</blockquote>
I liked the FAQ entry written up by the original submitter much better,
WRT to the long index issue.&nbsp; 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.&nbsp; It doesn't contain the optional
workaround, and it doesn't have a link into the full text searching
features as the recommended fix.&nbsp; I was one of the 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 are going 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>
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