How many different types of indexes we have in oracle?
Answers were Sorted based on User's Feedback
Answer / sathish
B TREE INDEX
FUNCTION BASED INDEX
REVERSE KEY INDEX
BIT MAP INDEX
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / rohit
In Oracle there are two types of SQL index namely, implicit and explicit.
Implicit Indexes:
They are created when a column is explicity defined with PRIMARY KEY, UNIQUE KEY Constraint.
Explicit Indexes:
They are created using the "create index.. " syntax.
NOTE:
1) Even though sql indexes are created to access the rows in the table quickly, they slow down DML operations like INSERT, UPDATE, DELETE on the table, because the indexes and tables both are updated along when a DML operation is performed. So use indexes only on columns which are used to search the table frequently.
2) Is is not required to create indexes on table which have less data.
3) In oracle database you can define up to sixteen (16) columns in an INDEX.
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / shankar
1.B-tree indexes:
B-tree indexes have the following subtypes:
Index-organized tables
Reverse key indexes
Descending indexes
B-tree cluster indexes
2.Bitmap and bitmap join indexes
3.Function-based indexes
4.Application domain indexes
Is This Answer Correct ? | 0 Yes | 0 No |
How to retrieve the count of updated rows?
Why we use bulk collect in oracle?
How to create an initialization parameter file?
Is postgres faster than oracle?
How to recover a dropped index?
What exactly do quotation marks around the table name do?
Define the terms primary key foreign key and also the difference between primary and the unique key
How to restrict the duplicate records in table valuesets
Explain an exception and its types?
Whats the benefit of dbms_stats over analyze?
what diffrence between function and procedure?
how to find the n'th highest salary from emp ?