I have a mysql stored procedure in which I want to write a composite If statement. Let a, b,c be the variables then In what order the following if will execute.
IF (a AND c=0) OR (b AND c=0) OR (!a AND !b) THEN
execute the code....
The above If statement not working properly. Is there any problem in the statement? I actually want to know the precedence of AND, OR operators.
I think you want:
IF (a IS NOT NULL AND c=0) OR (b IS NOT NULL AND c=0) OR (a IS NOT NULL AND b IS NOT NULL) THEN
execute the code....
In SQL, NULL
does not act like FALSE
; SQL uses 3-state logic where an expression can be TRUE
, FALSE
, or NULL
, and all comparisons with NULL
are FALSE
. See the documentation Working with NULL Values .
If statement allows you to execute a set of SQL statements based on condition. If certain condition returns true then statement executes, otherwise not.
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