Is not null in mysql stored procedure?
I have a MySQL stored procedure where I find the max value from a table. Show If there is no value I want to set the variable to yesterday's date.
The problem is that The following code is not being executed for some reason
How can I set the variable
asked Aug 28, 2013 at 23:06
2
Try: UPDATE Example:
answered Aug 28, 2013 at 23:16
wchiquitowchiquito 15.8k2 gold badges33 silver badges45 bronze badges 10 To check for NULL or empty variable, use the IF condition. Let us create a stored procedure − mysql> delimiter // mysql> create procedure checkingForNullDemo(Name varchar(20)) begin if Name is NULL OR Name='' then select 'Adam Smith'; else select Name; end if ; end // Query OK, 0 rows affected (0.00 sec) mysql> delimiter ; Case 1 When NULL is passed. Call the stored procedure using call command mysql> call checkingForNullDemo(NULL); This will produce the following output − +------------+ | Adam Smith | +------------+ | Adam Smith | +------------+ 1 row in set (0.00 sec) Query OK, 0 rows affected, 1 warning (0.00 sec) Case 2 When a value is passed. Call the stored procedure using the call command mysql> call checkingForNullDemo('John Doe'); This will produce the following output − +----------+ | Name | +----------+ | John Doe | +----------+ 1 row in set (0.00 sec) Query OK, 0 rows affected (0.00 sec)
Updated on 25-Feb-2020 13:02:51
IS NOT NULL in MySQL?The NOT NULL constraint enforces a column to NOT accept NULL values. This enforces a field to always contain a value, which means that you cannot insert a new record, or update a record without adding a value to this field.
Is NULL and is not null in MySQL?“IS NULL” is the keyword that performs the Boolean comparison. It returns true if the supplied value is NULL and false if the supplied value is not NULL. “NOT NULL” is the keyword that performs the Boolean comparison. It returns true if the supplied value is not NULL and false if the supplied value is null.
IS NOT NULL operator in SQL?Description. The IS NOT NULL condition is used in SQL to test for a non-NULL value. It returns TRUE if a non-NULL value is found, otherwise it returns FALSE. It can be used in a SELECT, INSERT, UPDATE, or DELETE statement.
Is NULL or is not null?The IS NULL condition is satisfied if the column contains a null value or if the expression cannot be evaluated because it contains one or more null values. If you use the IS NOT NULL operator, the condition is satisfied when the operand is column value that is not null, or an expression that does not evaluate to null.
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