Tagged Questions
5
votes
2answers
149 views
Cardinality rule for bitmap indexes
The Oracle documentation includes the following advice:
A bitmap index should be built on each of the foreign key columns of
the fact table or tables
In that reference, there is even a bitmap ...
1
vote
1answer
90 views
What is the best relationship model for high performance?
I want to model a relationship between Customer and Transaction.
However, because Customer is only described by a unique string and no extra info, I have two possibilities to implement it in the ...
4
votes
2answers
750 views
How I should fix the following update statement to make it run faster?
I have the following DML:
UPDATE rc_usutb011 u
SET cod_ant=(
SELECT cod_hst
FROM rc_pdptb101 p
WHERE ocip_hst=ocip_ant
AND p.sector=u.sector
);
The explain plan ...
0
votes
1answer
95 views
Creating Indexes to optimize query
I have this query and I want to increase its performance by adding appropriate Indexes.
DELETE
FROM MYTAB1
WHERE MYID1 IN
( SELECT MYID2 FROM MYTAB2 );
I am not familiar with the ...
3
votes
1answer
701 views
Oracle not using index when > used in where clause
We have a relatively classic scenario where the date clause of the query generated by the application uses a "greater than" for a given date.
Because there is no end clause to the date range, oracle ...
