Derik Whittaker

I couldn't agree more.  

It pains me to no end when I have to work with this kind of code.  The performance difference is ridiculously trivial at this point, but the difference in maintainability is massive.

From time to time, I have to support a VB6/SQL Server 6.5 legacy app that takes it even farther.  It uses column indexes and SELECT * in a way that precludes even appending a new column to certain tables in the database.

Derik,

You're right. But even in such trival examples i see authors still use "Estimated". Please even though it speeks for itself use constants or readonly properties.

No offence but some people just take the word 'writing' of the author.

Derik,

Usage of constant instead of magic string is better, if used in multiple places.

If one is worried about column name changes, use of an alias can help.

e.g. if The column name in TABLE is "Estimate" - the query could be written as "SELECT Estimate as EstimatedDate FROM TABLEA"

In this case, the .net code can use alias name to retrieve values. Changing of the column name in table won't break the code.

Lets further break the code.

Datarow firstrow = table.rows[0];

int estimatevalue = firstrow["estimateddate"];

Pardon my c# code above.

Derik,

In my experience if you introduce a constant, even if it is only used once other developers are more eager to use it. I've seen a lot of copy paste of the 'Magic string'. But this is just my experience.