what is HASH join?

Answer Posted / ankush

A hash join is a join optimization method where two tables
are joined based on a hashing algorithm.

Hashing refers to the conversion of a column's primary key
value to a database page number on which the row will be
stored. Retrieval operations that specify the key column
value use the same hashing algorithm and can locate the row
directly. Hashing provides fast retrieval for data that
contains a unique key value.

Note that a hash value cannot be converted back to the
original value.

Is This Answer Correct ?    4 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is procedure and function in sql?

740


What is sql*loader and what is it used for?

740


what does it mean to have quoted_identifier on? What are the implications of having it off? : Sql dba

718


What is loop in pl sql?

759


How many sql core licenses do I need?

677






What is recursive join in sql?

750


What is pl sql variable?

697


What is difference between inner join and cross join?

713


What is the difference between an inner join and an outer join?

716


What is 19 null in sql?

703


what is the difference difference between procedure and packages

9643


What is join view in sql?

696


How do you optimize a query?

724


What are local and global variables and their differences?

803


What are the set operators in sql?

771