Frequently Asked Questions (FAQ) for PostgreSQL
- Last updated: Wed Apr 17 22:48:04 EDT 2002
+ Last updated: Thu Apr 18 00:44:51 EDT 2002
Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
4.5) What is the maximum size for a row, a table, and a database?
4.6) How much database disk space is required to store data from a
typical text file?
- 4.7) How do I find out what tables or indexes are defined in the
- database?
+ 4.7) How do I find out what tables, indexes, databases, and users are
+ defined?
4.8) My queries are slow or don't make use of the indexes. Why?
4.9) How do I see how the query optimizer is evaluating my query?
4.10) What is an R-tree index?
Indexes do not require as much overhead, but do contain the data that
is being indexed, so they can be large also.
- 4.7) How do I find out what tables or indexes are defined in the database?
+ 4.7) How do I find out what tables, indexes, databases, and users are
+ defined?
psql has a variety of backslash commands to show such information. Use
- \? to see them.
+ \? to see them. There are also system tables beginning with pg_ that
+ describe these too. Also, psql -l will list all databases.
Also try the file pgsql/src/tutorial/syscat.source. It illustrates
many of the SELECTs needed to get information from the database system
alink="#0000ff">
<H1>Frequently Asked Questions (FAQ) for PostgreSQL</H1>
- <P>Last updated: Wed Apr 17 22:48:04 EDT 2002</P>
+ <P>Last updated: Thu Apr 18 00:44:51 EDT 2002</P>
<P>Current maintainer: Bruce Momjian (<A href=
"mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)<BR>
table, and a database?<BR>
<A href="#4.6">4.6</A>) How much database disk space is required
to store data from a typical text file?<BR>
- <A href="#4.7">4.7</A>) How do I find out what tables or indexes
- are defined in the database?<BR>
+ <A href="#4.7">4.7</A>) How do I find out what tables, indexes,
+ databases, and users are defined?<BR>
<A href="#4.8">4.8</A>) My queries are slow or don't make use of
the indexes. Why?<BR>
<A href="#4.9">4.9</A>) How do I see how the query optimizer is
<P>Indexes do not require as much overhead, but do contain the data
that is being indexed, so they can be large also.</P>
- <H4><A name="4.7">4.7</A>) How do I find out what tables or indexes
- are defined in the database?</H4>
+ <H4><A name="4.7">4.7</A>) How do I find out what tables, indexes,
+ databases, and users are defined?</H4>
<P><I>psql</I> has a variety of backslash commands to show such
- information. Use \? to see them.</P>
+ information. Use \? to see them. There are also system tables
+ beginning with <i>pg_</i> that describe these too. Also, <i>psql
+ -l</i> will list all databases.</P>
<P>Also try the file <I>pgsql/src/tutorial/syscat.source</I>. It
illustrates many of the <SMALL>SELECT</SMALL>s needed to get