select MIN/MAX when no row selected

From: "Ricardo Coelho" <rcoelho(at)px(dot)com(dot)br>
To: <pgsql-hackers(at)postgresql(dot)org>
Subject: select MIN/MAX when no row selected
Date: 1999-11-17 10:08:51
Message-ID: 002401bf30e3$c1a6b260$03fafdc8@px.com.br
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Hi All,

I think I had read this question with count(*) before.....

PgSql returns one row with a null field when we use select MIN or MAX on a
table, but the result should be "no rows selected".

I didn't try with C function, but I got the same result with psql.

So, I'm sending a Java example to Peter.

try {
rs=stmt.executeQuery("select min(field1) from tab where
field1>maxValueOfField1");
if (rs.next()) {
System.out.println("I found a row !!!!");
theResult=rs.getString(1);
if (theResult==null)
System.out.println("Min of field1 is NULL !!!!");
}
} catch (.............

maxValueofField1 = select max(field1) from tab;

Is it correct ?

I'm using PgSql 6.5.2, RHLinux/Intel 6.0

Thanks,

Ricardo Coelho.

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