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Update FAQ.
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doc/FAQ

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@@ -67,14 +67,14 @@
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4.6) What is the maximum size for a row, table, database?
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4.7) How much database disk space is required to store data from a
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typical text file?
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4.8) How do I find out what indices or operations are defined in the
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4.8) How do I find out what tables or indexes are defined in the
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database?
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4.9) My queries are slow or don't make use of the indexes. Why?
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4.10) How do I see how the query optimizer is evaluating my query?
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4.11) What is an R-tree index?
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4.12) What is Genetic Query Optimization?
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4.13) How do I do regular expression searches and case-insensitive
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regular expression searches?
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4.12) What is the Genetic Query Optimizer?
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4.13) How do I perform regular expression searches and
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case-insensitive regular expression searches?
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4.14) In a query, how do I detect if a field is NULL?
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4.15) What is the difference between the various character types?
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4.16.1) How do I create a serial/auto-incrementing field?
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Why?
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4.22) How do I create a column that will default to the current time?
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4.23) Why are my subqueries using IN so slow?
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4.24) How do I do an outer join?
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4.24) How do I perform an outer join?
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Extending PostgreSQL
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Indexes do not require as much overhead, but do contain the data that
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is being indexed, so they can be large also.
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4.8) How do I find out what indices or operations are defined in the
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database?
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4.8) How do I find out what tables or indexes are defined in the database?
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psql has a variety of backslash commands to show such information. Use
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\? to see them.
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extending R-trees requires a bit of work and we don't currently have
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any documentation on how to do it.
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4.12) What is Genetic Query Optimization?
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4.12) What is the Genetic Query Optimizer?
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The GEQO module speeds query optimization when joining many tables by
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means of a Genetic Algorithm (GA). It allows the handling of large
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join queries through nonexhaustive search.
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4.13) How do I do regular expression searches and case-insensitive regular
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expression searches?
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4.13) How do I perform regular expression searches and case-insensitive
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regular expression searches?
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The ~ operator does regular expression matching, and ~* does
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case-insensitive regular expression matching. There is no
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case-insensitive variant of the LIKE operator, but you can get the
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effect of case-insensitive LIKE with this:
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WHERE lower(textfield) LIKE lower(pattern)
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case-insensitive regular expression matching. The case-insensitive
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variant of LIKE is called ILIKE.
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4.14) In a query, how do I detect if a field is NULL?
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You test the column with IS NULLIS NOT NULL.
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Depending on your shell, only one of these may succeed, but it will
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set your process data segment limit much higher and perhaps allow the
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query to complete. This command applies to the current process, and
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all subprocessesHTML & CSS specifications are available from
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http://www.w3.org/ To learn more about Tidy see
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http://www.w3.org/People/Raggett/tidy/ Please send bug reports to Dave
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Raggett care of Lobby your company to join W3C, see
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http://www.w3.org/Consortium created after the command is run. If you
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are having a problem with the SQL client because the backend is
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returning too much data, try it before starting the client.
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all subprocesses created after the command is run. If you are having a
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problem with the SQL client because the backend is returning too much
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data, try it before starting the client.
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4.20) How do I tell what PostgreSQL version I am running?
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We hope to fix this limitation in a future release.
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4.24) How do I do an outer join?
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4.24) How do I perform an outer join?
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PostgreSQL 7.1 and later supports outer joins using the SQL standard
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syntax. Here are two examples:

doc/src/FAQ/FAQ.html

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@@ -103,15 +103,15 @@ <H2>Operational Questions</H2>
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database?<BR>
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<A href="#4.7">4.7</A>) How much database disk space is required
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to store data from a typical text file?<BR>
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<A href="#4.8">4.8</A>) How do I find out what indices or
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operations are defined in the database?<BR>
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<A href="#4.8">4.8</A>) How do I find out what tables or
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indexes are defined in the database?<BR>
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<A href="#4.9">4.9</A>) My queries are slow or don't make use of
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the indexes. Why?<BR>
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<A href="#4.10">4.10</A>) How do I see how the query optimizer is
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evaluating my query?<BR>
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<A href="#4.11">4.11</A>) What is an R-tree index?<BR>
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<A href="#4.12">4.12</A>) What is Genetic Query Optimization?<BR>
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<A href="#4.13">4.13</A>) How do I do regular expression searches
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<A href="#4.12">4.12</A>) What is the Genetic Query Optimizer?<BR>
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<A href="#4.13">4.13</A>) How do I perform regular expression searches
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and case-insensitive regular expression searches?<BR>
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<A href="#4.14">4.14</A>) In a query, how do I detect if a field
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is <SMALL>NULL</SMALL>?<BR>
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default to the current time?<BR>
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<A href="#4.23">4.23</A>) Why are my subqueries using
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<CODE><SMALL>IN</SMALL></CODE> so slow?<BR>
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<A href="#4.24">4.24</A>) How do I do an <I>outer</I> join?<BR>
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<A href="#4.24">4.24</A>) How do I perform an <I>outer</I> join?<BR>
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<CENTER>
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<P>Indexes do not require as much overhead, but do contain the data
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that is being indexed, so they can be large also.</P>
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<H4><A name="4.8">4.8</A>) How do I find out what indices or
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operations are defined in the database?</H4>
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<H4><A name="4.8">4.8</A>) How do I find out what tables or
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indexes are defined in the database?</H4>
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<P><I>psql</I> has a variety of backslash commands to show such
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information. Use \? to see them.</P>
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practice, extending R-trees requires a bit of work and we don't
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currently have any documentation on how to do it.</P>
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<H4><A name="4.12">4.12</A>) What is Genetic Query
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Optimization?</H4>
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<H4><A name="4.12">4.12</A>) What is the Genetic Query
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Optimizer?</H4>
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<P>The <SMALL>GEQO</SMALL> module speeds query optimization when
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joining many tables by means of a Genetic Algorithm (GA). It allows
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the handling of large join queries through nonexhaustive
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search.</P>
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<H4><A name="4.13">4.13</A>) How do I do regular expression
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<H4><A name="4.13">4.13</A>) How do I perform regular expression
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searches and case-insensitive regular expression searches?</H4>
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<P>The <I>~</I> operator does regular expression matching, and
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<I>~*</I> does case-insensitive regular expression matching. There
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is no case-insensitive variant of the <SMALL>LIKE</SMALL> operator,
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but you can get the effect of case-insensitive <SMALL>LIKE</SMALL>
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with this:</P>
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<PRE>
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WHERE lower(textfield) LIKE lower(pattern)
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</PRE>
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<I>~*</I> does case-insensitive regular expression matching. The
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case-insensitive variant of <SMALL>LIKE</SMALL>
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is called <SMALL>ILIKE</SMALL>.</P>
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<H4><A name="4.14">4.14</A>) In a query, how do I detect if a field
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is <SMALL>NULL</SMALL>?</H4>
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Depending on your shell, only one of these may succeed, but it will
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set your process data segment limit much higher and perhaps allow
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the query to complete. This command applies to the current process,
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and all subprocessesHTML & CSS specifications are available from http://www.w3.org/
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To learn more about Tidy see http://www.w3.org/People/Raggett/tidy/
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Please send bug reports to Dave Raggett care of <html-tidy@w3.org>
1153-
Lobby your company to join W3C, see http://www.w3.org/Consortium
1154-
created after the command is run. If you are
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and all subprocesses created after the command is run. If you are
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having a problem with the <SMALL>SQL</SMALL> client because the
11561148
backend is returning too much data, try it before starting the
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client.
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</PRE>
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We hope to fix this limitation in a future release.
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<H4><A name="4.24">4.24</A>) How do I do an <I>outer</I> join?<BR>
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<H4><A name="4.24">4.24</A>) How do I perform an <I>outer</I> join?<BR>
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</H4>
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<P>PostgreSQL 7.1 and later supports outer joins using the SQL

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