16.10 - Interpreting the Show Locks Display - Teradata Database

Teradata Database Utilities

Teradata Database
Release Number
June 2017
English (United States)
Last Update

The Show Locks utility display provides this information:

  • Summary of the showlocks function
  • Name of the databases, tables, and hash IDs on which locks are placed
  • Username that placed each lock
  • Lock mode: read, write, exclusive, or access
  • Identification numbers of the AMPs on which the locked database or table resides
  • Job identifier (only for DSA archive/recovery operations)
  • Proxy table locks, which enable sequential locking on all-AMP table locks

Show Locks reports All AMPs rather than individual AMP numbers when the locked database or table resides on all AMPs. Information is provided for only the most restrictive lock a user has placed on an object.

When no locks are found, Showlocks reports this message:

There are currently no host utility locks in the DBS.

Example: Show Locks Output with ARC HUT Locks

In this example, exclusive locks are placed on the employee table in the personnel database and on the entire service database. One read lock is placed on the parts database, and another read lock on the invoice table in the accounting database.

    Show Locks Utility

     This program queries all AMPs and reports all Host Utility locks.
 which currently exist at both the data base level and the table level.

 For each lock which is found, an entry will appear on your console
 which includes the following information:
- Data Base Name
- Table Name (if applicable)
- HashID (if applicable)
- User Name of user who placed lock
- Lock Mode
- AMP Number
- JobId of DSA Job (if applicable)
- PROXY LOCK (if applicable)

   USER ADMIN    MODE Read    AMP  All AMPs
   USER PETERS   MODE Read    AMP  24
   USER ACCMGR   MODE Excl    AMP  27
   USER DBC      MODE Excel   AMP  3
--ShowLocks Processing Complete--

The following locks have also been applied.

Username... Placed the lock on the...
ADMIN invoice table that resides on all AMPs.
PETERS parts database which resides on AMP 24.
ACCMGR portion of the employee table that resides on AMP 27.
DBC portion of the service database that resides on AMP 3.

Example: Show Locks Output with DSA Database-Level HUT Lock

 USER DBC   MODE Read     AMP All Amps JobId: 1300542

Example: Show Locks Output with DSA Object-Level HUT Lock

 USER DBC  MODE Read     AMP All Amps JobId: 3400241 
 USER DBC  MODE Read     AMP 1        JobId: 3400241  PROXY LOCK