Is it necessary to include "BEGIN" and "END" statements in a SQL script?
Hi. A programmer came in and helped us generate a lot of SQL code. I'm a novice SQL user but I can follow along and decipher what steps are being performed so am reviewing to understand the general flow of the application better. I noticed that in many places the programmer did not use BEGIN and END statements, while in other places, they are being used. Is this just good syntax or are these statements required to perform some functions while others, not so much? A couple of the Sprocs with these statements included are simply calling out table updates but same thing is happening in another sproc and the begin/end statement are not used. thanks
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A stored procedure does not require an outer BEGIN/END statement. There is not harm in adding them to a stored procedure but they aren't necessary. It comes down to local coding standards and personal preference really.
However, a user-defined function DOES require a BEGIN & END.
Within a procedure, say for an IF statement you must include a BEGIN/END if there is more than one statement associated with the conditional. They are not necessary but good practice to always have a BEGIN/END even for a single statement.
i.e.
IF (@A = @B)
BEGIN
-- do something
END
is equivalent to
IF (@A = @B)
--do something
However, a user-defined function DOES require a BEGIN & END.
Within a procedure, say for an IF statement you must include a BEGIN/END if there is more than one statement associated with the conditional. They are not necessary but good practice to always have a BEGIN/END even for a single statement.
i.e.
IF (@A = @B)
BEGIN
-- do something
END
is equivalent to
IF (@A = @B)
--do something
In addition to the above correct answer couple of other places too, such as cursors and WHILE loops, but not many.
No points please, but to expand on Brian's comment, the reason it is good practice around an IF statement is to make sure you don't break logic if another statement is subsequently added. It is clear that it belongs inside the IF block. If you start with:
IF (@A = @B)
SET @B = @B + 1
SET @A = @A - 1
@B will be incremented only if @A and @B are equal and @A will ALWAYS be decremented. Using BEGIN/END makes it clear exactly what should be associated with the IF statement.
IF (@A = @B)
SET @B = @B + 1
SET @A = @A - 1
@B will be incremented only if @A and @B are equal and @A will ALWAYS be decremented. Using BEGIN/END makes it clear exactly what should be associated with the IF statement.
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