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1 files changed, 22 insertions, 25 deletions
diff --git a/doc/src/FAQ/FAQ.html b/doc/src/FAQ/FAQ.html index b1ca31a3855..0bc7cd27d4d 100644 --- a/doc/src/FAQ/FAQ.html +++ b/doc/src/FAQ/FAQ.html @@ -10,7 +10,7 @@ alink="#0000ff"> <H1>Frequently Asked Questions (FAQ) for PostgreSQL</H1> - <P>Last updated: Thu Dec 5 00:47:26 EST 2002</P> + <P>Last updated: Fri Feb 14 09:03:00 EST 2003</P> <P>Current maintainer: Bruce Momjian (<A href= "mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)<BR> @@ -18,10 +18,10 @@ <P>The most recent version of this document can be viewed at <A href= - "http://www.PostgreSQL.org/docs/faq-english.html">http://www.PostgreSQL.org/docs/faq-english.html</A>.</P> + "http://www.ca.PostgreSQL.org/docs/faq-english.html">http://www.ca.PostgreSQL.org/docs/faq-english.html</A>.</P> <P>Platform-specific questions are answered at <A href= - "http://www.PostgreSQL.org/users-lounge/docs/faq.html">http://www.PostgreSQL.org/users-lounge/docs/faq.html</A>.</P> + "http://www.ca.PostgreSQL.org/users-lounge/docs/faq.html">http://www.ca.PostgreSQL.org/users-lounge/docs/faq.html</A>.</P> <HR> <H2 align="center">General Questions</H2> @@ -314,11 +314,11 @@ '#PostgreSQL' "$USER" irc.phoenix.net.</CODE></P> <P>A list of commercial support companies is available at <A href= - "http://www.PostgreSQL.org/users-lounge/commercial-support.html">http://www.PostgreSQL.org/users-lounge/commercial-support.html</A>.</P> + "http://www.ca.PostgreSQL.org/users-lounge/commercial-support.html">http://www.ca.PostgreSQL.org/users-lounge/commercial-support.html</A>.</P> <H4><A name="1.7">1.7</A>) What is the latest release?</H4> - <P>The latest release of PostgreSQL is version 7.2.3.</P> + <P>The latest release of PostgreSQL is version 7.3.2.</P> <P>We plan to have major releases every four months.</P> @@ -327,7 +327,7 @@ <P>Several manuals, manual pages, and some small test examples are included in the distribution. See the <I>/doc</I> directory. You can also browse the manual online at <A href= - "http://www.PostgreSQL.org/users-lounge/docs/">http://www.PostgreSQL.org/users-lounge/docs/</A>.</P> + "http://www.ca.PostgreSQL.org/users-lounge/docs/">http://www.ca.PostgreSQL.org/users-lounge/docs/</A>.</P> <P>There are two PostgreSQL books available online at <A href= "http://www.PostgreSQL.org/docs/awbook.html">http://www.PostgreSQL.org/docs/awbook.html</A> @@ -536,8 +536,8 @@ interface?</H4> Yes, there are several graphical interfaces to PostgreSQL available. - These include PgAccess <a href="http://www.pgaccess.com"> - http://www.pgaccess.com</a>), PgAdmin II (<a + These include PgAccess <a href="http://www.pgaccess.org"> + http://www.pgaccess.org</a>), PgAdmin II (<a href="http://www.pgadmin.org">http://www.pgadmin.org</a>, Win32-only), RHDB Admin (<a href="http://sources.redhat.com/rhdb/">http://sources.redhat.com/rhdb/ @@ -547,10 +547,6 @@ http://phppgadmin.sourceforge.net/ </a>), a web-based interface to PostgreSQL. - <P>We have a nice graphical user interface called PgAccess which can - also be used as a report generator. The Web page is - <A href="http://www.pgaccess.org/">http://www.pgaccess.org/</A>.</P> - <H4><A name="2.4">2.4</A>) What languages are able to communicate with PostgreSQL?</H4> @@ -757,11 +753,6 @@ the number of allowed backend processes is so your system won't run out of resources.</P> - <P>In PostgreSQL versions prior to 6.5, the maximum number of - backends was 64, and changing it required a rebuild after altering - the MaxBackendId constant in - <I>include/storage/sinvaladt.h</I>.</P> - <H4><A name="3.9">3.9</A>) What is in the <I>pgsql_tmp</I> directory?</H4> <P>This directory contains temporary files generated by the query @@ -947,6 +938,10 @@ LIMIT 1; </PRE> + <P>If you believe the optimizer is incorrect in choosing a + sequential scan, use <CODE>SET enable_seqscan TO 'off'</CODE> and + run tests to see if an index scan is indeed faster.</P> + <P>When using wild-card operators such as <SMALL>LIKE</SMALL> or <I>~</I>, indexes can only be used in certain circumstances:</P> <UL> @@ -1039,10 +1034,10 @@ <PRE> Type Internal Name Notes -------------------------------------------------- -"char" char 1 character -CHAR(n) bpchar blank padded to the specified fixed length VARCHAR(n) varchar size specifies maximum length, no padding +CHAR(n) bpchar blank padded to the specified fixed length TEXT text no specific upper limit on length +"char" char one character BYTEA bytea variable-length byte array (null-byte safe) </PRE> @@ -1056,11 +1051,13 @@ BYTEA bytea variable-length byte array (null-byte safe) stored out-of-line by <SMALL>TOAST</SMALL>, so the space on disk might also be less than expected.</P> - <P><SMALL>CHAR(n)</SMALL> is best when storing strings that are - usually the same length. <SMALL>VARCHAR(n)</SMALL> is best when - storing variable-length strings but it limits how long a string can - be. <SMALL>TEXT</SMALL> is for strings of unlimited length, maximum - 1 gigabyte. <SMALL>BYTEA</SMALL> is for storing binary data, + <SMALL>VARCHAR(n)</SMALL> is best when storing variable-length + strings and it limits how long a string can be. <SMALL>TEXT</SMALL> + is for strings of unlimited length, with a maximum of one gigabyte. + <P><SMALL>CHAR(n)</SMALL> is for storing strings that are all the + same length. <SMALL>CHAR(n)</SMALL> pads with blanks to the specified + length, while <SMALL>VARCHAR(n)</SMALL> only stores the characters + supplied. <SMALL>BYTEA</SMALL> is for storing binary data, particularly values that include <SMALL>NULL</SMALL> bytes. These types have similar performance characteristics.</P> @@ -1286,7 +1283,7 @@ BYTEA bytea variable-length byte array (null-byte safe) </PRE> For this to be fast, <CODE>subcol</CODE> should be an indexed column. - We hope to fix this limitation in a future release. + This preformance problem will be fixed in 7.4. <H4><A name="4.23">4.23</A>) How do I perform an outer join?</H4> |