Interested to Buy Any Domain ? << Click Here >> for more details...
Give the reasoning behind using an index.
- 2 Answers
- 6377 Views
- I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / pradeeshkumar
Its as simple as why do we need an index page in front of a
book. Whenever we wish to read a scpecific text from the
book, we'll first check the index and locate where that
specific text is. Similarly when create an index it enables
the queries to locate praticular row or entity in a table
by directly refering to the index instead of searching the
entire table. Whenever a table is created with a primary
key, an index ia automatically created on the primary key
column which makes easier access of table entries. When you
execute query say( select * from student where
student_id=10;), your query will first hit the index
(primary index on primary key column) and then will retrive
the corresponding row from the table. If there's no such
entry in the table, it'll return an empty result set
without searching the table.
| Is This Answer Correct ? | 0 Yes | 0 No |
Its as simple as why do we need an index page in front of a
book. Whenever we wish to read a scpecific text from the
book, we'll first check the index and locate where that
specific text is. Similarly when create an index it enables
the queries to locate praticular row or entity in a table
by directly refering to the index instead of searching the
entire table. Whenever a table is created with a primary
key, an index ia automatically created on the primary key
column which makes easier access of table entries. When you
execute query say( select * from student where
student_id=10;), your query will first hit the index
(primary index on primary key column) and then will retrive
the corresponding row from the table. If there's no such
entry in the table, it'll return an empty result set
without searching the table.
| Is This Answer Correct ? | 0 Yes | 0 No |
Explain an ORA-01555
How do you resize a data file?
What is index? How many types of indexes?
can u tell me how many types of oracle and which type all detail in oracle (suppose all history of oracle )
Hey i want to join oracle apps so will you pls tell me that which institute is best in hyderabad.
how to display last 5 letters from a name (take emp table ename )
what is different between inline query,subquery& corelated query?
What is the technical flow associated with P2P or Procure to Pay cycle like the tables, APIs, concurrent programs involved in this cycle. Only technical please.
What is mrc and what is its use? : oracle accounts receivable
Can we modify approve purchase order?if yes what is navigation?
1. What is PO rate variance gain and loss?
What do you mean by hz_ in customer tables? : oracle accounts receivable
Oracle General 
