Managing Query Performance - Teradata Database

You can monitor queries using the Teradata Viewpoint Query Monitor portlet and other tools and utilities to identify poorly performing queries. Poor query performance is usually due to:

Stale statistics. See “Collecting Statistics” on page 486.

Poor query construction. See “Finding and Fixing Problem Queries” on page 491.

Skewed query processing. See “Managing Skewed Processing” on page 493.

Skewed table distribution. See “Identifying and Fixing Skewed Tables” on page 495.

Locks that block queries from accessing needed data. See “Identifying and Managing Blocked Queries” on page 499.

This section also covers the performance issues related to transaction rollbacks, which occur when a query fails to complete. See “Working with Transaction Rollbacks” on page 501.