My teacher recently talked about the statement 'GOTO', to be used in Management Studio, but I didn't quite understand it at first. He stated that GOTO is being used to jump to different pieces of code, with the help of a label I can name by myself. This is the code he used to represent his example:
select 'first'
goto jump
select 'second'
jump:
select 'third'
When I execute the code, sure enough, it prints 'first' and 'third'. My question now is what was the select 'second' doing there in the first place?
In your example, the second select is clearly unnecessary.
GOTO is an example of "control-flow" for the the program code. It is a construct from the earliest computer languages, one that maps directly onto how the hardware works when processing languages such as C or assembly code. Since then, it has been included in many other languages.
GOTO would often be used with IF. However, T-SQL offers better control flow functionality, such as:
In general, you should be using these constructs and not GOTO. In fact, GOTO is rather controversial. Many people think it is always a sign of poor code ("spaghetti code" is sometimes used to describe this type of code). Others will make a very rare exception for something like exception handling (which I sometimes do) or some types of state machines.
In my opinion, GOTO should only be taught after all the other constructs and only for very specific purposes.