How to Know Teradata is in Pseudo table Lock

The pseudo table mechanism is a way to serially queue all table level locks through the use of an internal pseudo table. In this table the database locks the row hash of the table's table ID.


What does” Pseudo Table” Locks mean in EXPLAIN Plan in Teradata:

  1. It is a false lock which is applied on the table to prevent two users from getting conflicting locks with all-AMP requests. PE will determine an particular AMP to manage all AMP LOCK requests for given table and Put Pseudo lock on the table.

  3. To put in Simple terms: its like an University with 10 gates and at a given time you can enter the university through one gate ( or main gate) for security check.

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