About case when and the sql clause

Question

Hi:
The following is my sql clause:
SELECT t.*,b.name
FROM dbtest1 t
LEFT OUTER JOIN dbtest b ON t.NO = b.empno
WHERE t.ChineseName like '%'||:ChineseName||'%' AND b.name like '%'||:name||'%'
ORDER BY t.ChineseName
The main problem is I hope to check the b.name if it is null it can be passed as NVL function, so I try using case when, but it not working.
When b.name exist in where clause, the result columns will not include the data without b.name(or implies the b.name is NULL); And that
make the result data not exactly right.
is it possible to use case when to make the following snippet implemented:
case when b.name is not NULL then b.name like '%'||:name||'%'
else b.name = NULL(b.name=b.name seems not work to parsing null data)
end
Thanks a lot.

Answer 1

962769 wrote:
Hi:
The following is my sql clause:
SELECT t.*,b.name
FROM dbtest1 t
LEFT OUTER JOIN dbtest b ON t.NO = b.empno
WHERE t.ChineseName like '%'||:ChineseName||'%' AND b.name like '%'||:name||'%'
ORDER BY t.ChineseName
The main problem is I hope to check the b.name if it is null it can be passed as NVL function, so I try using case when, but it not working.
When b.name exist in where clause, the result columns will not include the data without b.name(or implies the b.name is NULL); And that
make the result data not exactly right.
is it possible to use case when to make the following snippet implemented:
case when b.name is not NULL then b.name like '%'||:name||'%'
else b.name = NULL(b.name=b.name seems not work to parsing null data)
end
Thanks a lot.Your question isn't very clear. But below is the statement as I make a meaning out of it.
SELECT t.*,b.name
FROM dbtest1 t
LEFT OUTER JOIN dbtest b ON t.NO = b.empno
WHERE t.ChineseName like '%'||:ChineseName||'%'
     AND b.name like '%'||NVL(:name, b.name)||'%'
ORDER BY t.ChineseNameIf you want to use case, then:
SELECT t.*,b.name
FROM dbtest1 t
LEFT OUTER JOIN dbtest b ON t.NO = b.empno
WHERE t.ChineseName like '%'||:ChineseName||'%'
     AND b.name like '%'|| case when b.name is not null then :name else b.name end ||'%'
ORDER BY t.ChineseNameIf this is not what you are looking for then, read {message:id=9360002} and post the relevant details with an example (Create Table script, Sample Data creation script and the Expected output of the sample data).