Alternative for Multiple Left outer join

Database

Alternative for Multiple Left outer join

Select coalesce (t1.col3,p1.col3) as target_Column1,
coalesce (t2.col3,p2.col3) as target_Column2,
coalesce (t3.col3,p3.col3) as target_Column3,
...
coalesce (t25.col3,p25.col3) as target_Column3,
from
d1.g1_view a
join
d1.g1_metadate b
on
b.cd='some_cd'
left outer join
d1.val_table t1
on
t1.val_cd = a.some_ind
and t1.schm_Cd ='abc'
left outer join
d1.schm_tab p1
on
p1.schm_cd ='abc'

left outer join
d1.val_table t2
t1.val_cd = a.some_other_ind
and t1.schm_Cd ='pqr'
d1.schm_tab p2
on
p1.schm_cd ='pqr'
...
left outer join
d1.val_table t25
t1.val_cd = a.some_other_other_ind
and t1.schm_Cd ='xyz'
d1.schm_tab p25
on
p1.schm_cd ='xyz'

Hi All,

I have a view running for a very long time. Can anybody suggest me alternative for left outer joins to val table and the schm_tab. Thanks in advance.

Thanks,

DrmKd

1 REPLY
Teradata Employee

Re: Alternative for Multiple Left outer join

In one line, there is no alternative to LEFT OUTER JOIN.

Regarding fixing performance .... How are the tables designed? What the joining columns? What is the PI? .... search forum and you will get many scenarios of performance issues.

There is no magic to performant queries. :)