Query Blocks and Delays | Teradata Vantage - 17.00 - 17.05 - Investigating Query Blocks and Delays - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - Database Administration

Product
Advanced SQL Engine
Teradata Database
Release Number
17.00
17.05
Published
June 2020
Language
English (United States)
Last Update
2021-01-22
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Most blocks are momentary and do not require attention. However, if a block persists, you can investigate it to identify the cause and determine whether further action is required.

  1. Use the Teradata Viewpoint Query Monitor portlet to monitor the parameters related to query blocks and delays.
    State Description
    Blocked Indicates that a session query is held up by a lock on an object that the query is attempting to access.
    Blocked Time How long the query has been blocked.

    Momentary locks are normal and not harmful. Persistent locks may indicate:

    • A runaway query or hung query that cannot complete and release its locks, and which should be aborted
    • A long-running query, such as large-scale update or backup operation, which should be rescheduled to avoid resource contention
    Delayed Indicates that the query is in a delay queue caused by a workload rule.
  2. Click the session ID for the query to access the Details View.
    • If a query is blocked, see the Blocked By tab for details
    • If the query is delayed, the Delay tab provides details about the cause of the delay
  3. You can also use the Lock Viewer portlet to find out more about the block, including:
    • Block Time
    • Database
    • Table
    • Delay
    • Blocked User
    • Blocking Level
    • Blocking User