Add info about selecting a random row.

doc/FAQ

 
                 Frequently Asked Questions (FAQ) for PostgreSQL
                                        
-   Last updated: Mon May 26 15:25:04 EDT 2003
+   Last updated: Wed May 28 00:35:16 EDT 2003
    
    Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
    
@@ -58,7 +58,7 @@
                            Operational Questions
                                       
    4.1) What is the difference between binary cursors and normal cursors?
-   4.2) How do I SELECT only the first few rows of a query?
+   4.2) How do I SELECT only the first few rows of a query? A random row?
    4.3) How do I get a list of tables or other things I can see in psql?
    4.4) How do you remove a column from a table, or change it's data
    type?
@@ -627,7 +627,7 @@
     
    See the DECLARE manual page for a description.
    
-    4.2) How do I SELECT only the first few rows of a query?
+    4.2) How do I SELECT only the first few rows of a query? A random row?
     
    See the FETCH manual page, or use SELECT ... LIMIT....
    
@@ -637,6 +637,12 @@
    evaluate only the first few records requested, or the entire query may
    have to be evaluated until the desired rows have been generated.
    
+   To SELECT a random row, use:
+    SELECT col
+    FROM tab
+    ORDER BY random()
+    LIMIT 1;
+
     4.3) How do I get a list of tables or other things I can see in psql?
     
    You can read the source code for psql in file

doc/src/FAQ/FAQ.html

@@ -10,7 +10,7 @@
   alink="#0000ff">
     <H1>Frequently Asked Questions (FAQ) for PostgreSQL</H1>
 
-    <P>Last updated: Mon May 26 15:25:04 EDT 2003</P>
+    <P>Last updated: Wed May 28 00:35:16 EDT 2003</P>
 
     <P>Current maintainer: Bruce Momjian (<A href=
     "mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)<BR>
@@ -83,7 +83,7 @@
     <A href="#4.1">4.1</A>) What is the difference between binary
     cursors and normal cursors?<BR>
      <A href="#4.2">4.2</A>) How do I <SMALL>SELECT</SMALL> only the
-    first few rows of a query?<BR>
+    first few rows of a query?  A random row?<BR>
      <A href="#4.3">4.3</A>) How do I get a list of tables or other
     things I can see in <I>psql</I>?<BR>
      <A href="#4.4">4.4</A>) How do you remove a column from a
@@ -799,7 +799,7 @@
     description.</P>
 
     <H4><A name="4.2">4.2</A>) How do I <SMALL>SELECT</SMALL> only the
-    first few rows of a query?</H4>
+    first few rows of a query?  A random row?</H4>
 
     <P>See the <SMALL>FETCH</SMALL> manual page, or use
     <SMALL>SELECT</SMALL> ... <SMALL>LIMIT</SMALL>....</P>
@@ -811,6 +811,14 @@
     records requested, or the entire query may have to be evaluated
     until the desired rows have been generated.</P>
 
+    <P>To <SMALL>SELECT</SMALL> a random row, use:
+<PRE>
+    SELECT col
+    FROM tab
+    ORDER BY random()
+    LIMIT 1;
+</PRE>
+
     <H4><A name="4.3">4.3</A>) How do I get a list of tables or other
     things I can see in <I>psql</I>?</H4>