TSQL Create table inside case statement

Question

The code below tries to use case condition to create a table or another. What would be the sql way to express that?

DECLARE @tmp VARCHAR(255)

SET @tmp = 'A'

SELECT CASE @tmp
WHEN 'A' THEN CREATE TABLE #Hello (ID Int, Hello varchar)
WHEN 'B' THEN CREATE TABLE #Goodbye (ID Int, Goodby varchar)
END

Answer 1

Instead of a CASE statement, simply use IF, since inside the CASE statement you cannot control the flow of execution of TSQL Statements or use DDL statements.

As per @ Zohar Peled's comment, I am adding an arbitrary length to the varchar fields, since they had been declared without any:

DECLARE @tmp VARCHAR(255)

SET @tmp = 'A'
IF @tmp = 'A'  
BEGIN 
 --PRINT 'Creating table #Hello'
 CREATE TABLE #Hello (ID Int, Hello varchar(128))
END
ELSE
IF @tmp = 'B'
BEGIN
 --PRINT 'Creating table #Goodbye'
 CREATE TABLE #Goodbye (ID Int, Goodby varchar(128))
END