How to join tables on values : Table 1:  
Col A | Col B | Col C | Col D  
Cat 1   | Bla a | C-1 | D-1  
Cat 1   | Bla a | C-2 | D-2  
Cat 1   | Bla a | C-3 | D-3  
Cat 2   | Bla b | C-4 | D-4   
Cat 2   | Bla b | C-5 | D-5  

Table 2:  
Col A | Col B | Col E  
Cat 1   | Bla a | E-1   
Cat 2   | Bla b | E-2   
Cat 2   | Bla b | E-3   
Cat 2   | Bla b | E-4

Desired Table:  
Col A | Col B | Col C | Col D | Col E  
Cat 1   | Bla a | C-1 | D-1  | E-1   
Cat 1   | Bla a | C-2 | D-2  | NULL  
Cat 1   | Bla a | C-3 | D-3  | NULL  
Cat 2   | Bla b | C-4 | D-4  | E-2    
Cat 2   | Bla b | C-5 | D-5  | E-3   
Cat 2   | Bla b | NULL  | NULL  | E-4

I want to add Column E of Table 1 to Table 2. I want to Match Columns A and B of both Tables. There is no correlation between columns C and D to Column E. I have tried Inner and outer joins, What I get is:

Wrong Table:  
Col A | Col B | Col C | Col D | Col E  
Cat 1   | Bla a | C-1 | D-1  | E-1     
Cat 1   | Bla a | C-2 | D-2  | E-1    
Cat 1   | Bla a | C-3 | D-3  | E-1    
Cat 2   | Bla b | C-4 | D-4  | E-2  
Cat 2   | Bla b | C-4 | D-4  | E-3  
Cat 2   | Bla b | C-4 | D-4  | E-4  
Cat 2   | Bla b | C-5 | D-5  | E-2       
Cat 2   | Bla b | C-5 | D-5  | E-3  
Cat 2   | Bla b | C-5 | D-5  | E-4    

Please Help. Thank You
