performance boost by seemingly unnecessary string initialization?

Question

At the moment I maintain a quirky codebase, and came across the following same pattern more than 100 times:

string NotMySqlQuery = ""; //why initialize the string with "", only to overwrite it on the next line?
NotMySqlQuery = "The query to be executed";

Since I came across this so often, I now doubt my own good judgement.

Is this a trick to optimize the compiler or does it bring any other advantages?

It reminds me a bit of the old times when I did write some code in C++, but it still doesn't look like proper dealing with strings to me.

Why would someone write code like that?

Answer 1

There is no performance advantage of that syntax. It is even slightly worse than not initializing it at all, since the strings are immutable in c# and this way 2 separate strings are allocated.

Answer 2

For your simple case, it is better to save the 2 lines into one, there is no point to assign it an empty string, and immediately assign another value to it.

string NotMySqlQuery = "The query to be executed";

This is clearer.