Dear friends,
My oracle version is 10 G.
I have a table vactype,this table contains vac id column have null values.
i want to create an index in vac id column is possible create index in null
column?
Any body help me.
Expecting ur replies..
Hastha23.
4  2802 
Dear friends,
My oracle version is 10 G.
I have a table vactype,this table contains vac id column have null values.
i want to create an index in vac id column is possible create index in null
column?
Any body help me.
Expecting ur replies..
Hastha23.
Hi Hastha,
It is possible to create index on a column which contains NULL values.
Regards,
Pradeep.
dear friend,
which index i choosing?
unique ,non unique is possible to create index in null column?
PLease replies..
dear friend,
which index i choosing?
unique ,non unique is possible to create index in null column?
PLease replies..
Hi hastha,
Unique Index is also possible.
Regards,
Pradeep.
Index will not be applied on the null values. Like if in a query i write
suppose i have the index on column_1 of table_1
and when i fire the query mentioned below
select * from table_1 where column_1 is null;
then index is not used.
for resolving it with some twiking, you can follow the link
http://www.dba-oracle.com/oracle_tips_nul l_idx.htm
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