Hive table join with update - sql

Question

I am a bit stuck , Can any one help me here. I have two tables with the below structure.
Table 1
Id String
Code1 String
Code2 String
Table 2
Id String
UserCode String
UniversalCode String
What i need to do is to replace all value in code1 and code2 with UniversalCode from the table 2. To be more clear , if code1 matches UserCode then repalce Code1 with universalCode and again for the same record if code2 matches with usercode then replace it with UniversalCode. If there is no match retain the value for code1 and code2. I need to have all records from table 1. Table 1 and Table 2 are connected via Id.
I tried the below for one column but got stuck adding code2
SELECT
Id,
CASE WHEN a.Code1 = b.UserCode then b.UniversalCode else a.Code1 end
from table1 a
LEFT OUTER JOIN table2 b ON (a.Id = b.Id and a.code1 = b.UserCode);
Any suggestions to get this done ? , The real scenario has 5-6 columns where i need to apply the same logic.
Test Data
Table 1
1,123,ABCD
1,ABCD,123
1,456,BCD
1,BCD,789
1,789,100
Table 2
1,123,XXX
1,456,YYY
1,789,ZZZ
2,123,XXX
2,456,YYY
2,789,ZZZ
Output
1,XXX,ABCD
1,ABCD,XXX
1,YYY,BCD
1,BCD,ZZZ
1,ZZZ,100
output with a.id=b.id in Join(Please refer below comments for this output)
1 123 XXX 100 100
1 123 123 100 100
1 123 123 100 100
1 ABCD ABCD 101 101
1 ABCD ABCD 101 101
1 ABCD ABCD 101 101
1 456 456 DEF DEF
1 456 YYY DEF DEF
1 456 456 DEF DEF
1 BCD BCD 789 789
1 BCD BCD 789 789
1 BCD BCD 789 ZZZ
1 789 789 CDE CDE
1 789 789 CDE CDE
1 789 ZZZ CDE CDE
1 100 100 HBT HBT
1 100 100 HBT HBT
1 100 100 HBT HBT
1 100 100 123 XXX
1 100 100 123 123
1 100 100 123 123

Answer 1

I'm not sure if I understand you but something like this should help you.
SELECT
a.Id
, CASE WHEN a.Code1 = b.UserCode THEN b.UniversalCode ELSE a.Code1 END AS Code1
, CASE WHEN a.Code2 = b.UserCode THEN b.UniversalCode ELSE a.Code2 END AS Code2
FROM table1 a
LEFT OUTER JOIN
table2 b
ON a.Id = b.Id;

Answer 2

We can try the below query:-
SELECT
Id,
CASE WHEN Code1 = UserCode then UniversalCode else Code1 end,
CASE WHEN Code2= UserCode then UniversalCode else Code2 end
from
(select a.id,a.Code1,a.Code2,b.UserCode,b.UniversalCode
from table1 a
LEFT OUTER JOIN table2 b ON (a.Id = b.Id and a.code1 = b.UserCode) union
select a.id,a.Code1,a.Code2,b.UserCode,b.UniversalCode
from table1 a
LEFT OUTER JOIN table2 b ON (a.Id = b.Id and a.code1 = b.UniversalCode)) dat ;