What is the difference between Primary Index & Secondar index in Teradata?...

 

Primary Index

Secondary Index

It can be created while creating a table.

It can able to create after table creation too.

It can't be modified…

If we need to change the PI then needs to drop the table and needs to recreate it along with new PI…

It can be modified.

Only one PI can able to create it in table

We can create around 64 columns oriented SI..

It will perform the full table scan

It will not perform the full table scan and it will improve the performance.

If we didn’t define the PI then TD will automatically will assign the PI

It’s an optional

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