SQL

sql select case when

--CREATE SOME SAMPLE DATA

CREATE TABLE Casedata
  (
     NAME VARCHAR(10)
  );

INSERT INTO Casedata VALUES ('Test 1');
INSERT INTO Casedata VALUES ('Test 2');
INSERT INTO Casedata VALUES ('None');

-- CASE WHEN IN SQL
SELECT NAME,
       CASE
         WHEN NAME = 'Test 1' THEN 'The value is 1'
         WHEN NAME = 'Test 2' THEN 'The value is 2'
         ELSE 'Sorry no Match'
       END
FROM   Casedata 

case statement in select query in sql

INSERT INTO HumanResources.departmentcopy(DepartmentID, GroupName, Name, temp)
SELECT  DepartmentID,
        GroupName,
        Name,
        CASE WHEN DepartmentID = 1 AND Name = 'Engineering and Research'
        THEN 'sucessful' ELSE 'unsucessful' END
FROM HumanResources.department

case statement in sql

Case Statement basically
Like IF - THEN - ELSE statement.

The CASE statement goes through conditions
and returns a value when the
first condition is met and
once a condition is true,
it will stop reading and return the result.
If no conditions are true,
it returns the value in the ELSE clause.

If there is no ELSE part and
no conditions are true, it returns NULL.

FOR EXAMPLE =

CASE
    WHEN condition1 THEN result1
    WHEN condition2 THEN result2
    WHEN conditionN THEN resultN
    ELSE result
END 

-- example:
SELECT 
	CASE
      WHEN (1+6 = 6) THEN 'A'
      WHEN (1+6 = 7) THEN 'B'
      WHEN (1+6 = 8) THEN 'C'
      ELSE 'D'
	END 
FROM DUAL;

Result would be 'B' since it is the first
correct answer