From: Warren Young
Date: March 20 2009 5:09am
Subject: Re: checking NULL
List-Archive: http://lists.mysql.com/plusplus/8492
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On Mar 19, 2009, at 10:50 PM, Jithin Emmanuel wrote:

>                                name = row["name"].get_string();

First, you really should consider upgrading to MySQL++ v3.  You're  
clearly still on 2.3 or earlier.  There have been probably half a  
dozen changes to the way we handle SQL nulls in v3.0.0 and later, some  
of them highly useful.

Second, my previous reply didn't say to convert the return value of  
Row::operator[]() to a std::string and then make the test.  I said to  
test the return value of Row::operator[]() directly.  Why?  Because  
there's nothing like SQL null in C or C++.  When you convert SQL data  
to a non-SQL data type, you lose the SQL null flag.  You must test for  
the flag before you make the conversion.