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Add info about selecting a random row.
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‎doc/FAQ

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Frequently Asked Questions (FAQ) for PostgreSQL
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Last updated: Mon May 26 15:25:04 EDT 2003
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Last updated: Wed May 28 00:35:16 EDT 2003
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Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
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Operational Questions
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4.1) What is the difference between binary cursors and normal cursors?
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4.2) How do I SELECT only the first few rows of a query?
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4.2) How do I SELECT only the first few rows of a query? A random row?
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4.3) How do I get a list of tables or other things I can see in psql?
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4.4) How do you remove a column from a table, or change it's data
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type?
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See the DECLARE manual page for a description.
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4.2) How do I SELECT only the first few rows of a query?
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4.2) How do I SELECT only the first few rows of a query? A random row?
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See the FETCH manual page, or use SELECT ... LIMIT....
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evaluate only the first few records requested, or the entire query may
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have to be evaluated until the desired rows have been generated.
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To SELECT a random row, use:
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SELECT col
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FROM tab
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ORDER BY random()
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LIMIT 1;
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4.3) How do I get a list of tables or other things I can see in psql?
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You can read the source code for psql in file

‎doc/src/FAQ/FAQ.html

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alink="#0000ff">
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<H1>Frequently Asked Questions (FAQ) for PostgreSQL</H1>
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<P>Last updated: Mon May 26 15:25:04 EDT 2003</P>
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<P>Last updated: Wed May 28 00:35:16 EDT 2003</P>
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<P>Current maintainer: Bruce Momjian (<A href=
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"mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)<BR>
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<A href="#4.1">4.1</A>) What is the difference between binary
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cursors and normal cursors?<BR>
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<A href="#4.2">4.2</A>) How do I <SMALL>SELECT</SMALL> only the
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first few rows of a query?<BR>
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first few rows of a query? A random row?<BR>
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<A href="#4.3">4.3</A>) How do I get a list of tables or other
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things I can see in <I>psql</I>?<BR>
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<A href="#4.4">4.4</A>) How do you remove a column from a
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description.</P>
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<H4><A name="4.2">4.2</A>) How do I <SMALL>SELECT</SMALL> only the
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first few rows of a query?</H4>
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first few rows of a query? A random row?</H4>
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<P>See the <SMALL>FETCH</SMALL> manual page, or use
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<SMALL>SELECT</SMALL> ... <SMALL>LIMIT</SMALL>....</P>
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records requested, or the entire query may have to be evaluated
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until the desired rows have been generated.</P>
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<P>To <SMALL>SELECT</SMALL> a random row, use:
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<PRE>
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SELECT col
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FROM tab
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ORDER BY random()
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LIMIT 1;
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</PRE>
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<H4><A name="4.3">4.3</A>) How do I get a list of tables or other
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things I can see in <I>psql</I>?</H4>
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