MultiLoad Sessions State Displays - Advanced SQL Engine - Teradata Database

Database Utilities

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
Published
January 2021
Language
English (United States)
Last Update
2021-01-23
dita:mapPath
ynh1604715438919.ditamap
dita:ditavalPath
hoy1596145193032.ditaval
dita:id
B035-1102
lifecycle
previous
Product Category
Teradata Vantageā„¢

Several displays are defined for the sessions that are part of MultiLoad operations.

The following sections describe those displays:

  • Preliminary Phase Sessions
  • Application Phase Session for Apply Task
  • Application Phase Session for Delete Task
  • Active Parent Session in an Acquisition Phase
  • Inactive Parent Session in an Acquisition Phase
  • Child Session in an Acquisition Phase

In addition to the phase State Detail line, a line describing the current phase is displayed.

If the session is in the Preliminary or Application phase, the current task type (Delete or Apply) is displayed. The information displayed is different for each phase: Preliminary, Application, and Acquisition. In the Application phase, each of the two task types is displayed.

When the action involves more than one AMP, row count summaries are meaningless and are not reported.

Preliminary Phase Session Display

The following shows an example display session, that is part of a MultiLoad operation, in the Preliminary phase.

State Details : Session involved in MLOAD utility
MLoad Phase : Preliminary - Received all DML Steps.
Task Running : Apply Task
               
Statements Dispatched Time     CPU Usage Accesses DMLCount
---------- ---------- -------- --------- -------- --------
        10          2 12:09:09         7       15        5

The possible tasks include Apply Task and Delete Task. These are the Subphases:

  • No MLOAD step has been received.
  • Receiving MLOAD step.
  • Received all MLOAD steps.
  • Received all DML (Data Manipulation Language) steps.

The state display for the preliminary phase of a MultiLoad operation contains the following information.

The column named... Contains the...
Statements total number of statements in the current session request.
Dispatched highest statement number dispatched to the AMPs.
Time time that the last step for the highest statement number was sent to the AMPs.
CPU Usage accumulated time in thousandths of a second that all AMPs spent processing the current request.
Accesses total number of segment access calls executed on all AMPs for the session request.
DML Count number of DML steps received if the current phase is Received all DML Steps.

Application Phase Session for Apply Task Display

The Query Session display for each table during an Apply Task includes the name of the database and table, the current action, the number of workrows applied, and the total number of workrows. The following shows an example display session involved in a MultiLoad operation during an Apply Task.

State Details : Session involved in MLOAD utility
MLoad Phase : Application.
Task Running : Apply Task
               
Statements Dispatched Time     CPU Usage Accesses
---------- ---------- -------- --------- --------
         1          1 11:09:37    811751  349,637
               
DataBase.Table                = SPOOL_RES.WT_TDEM_PAIMT_MEDfffffffffffffffffffffffffffAction                        = Process Data and Secondary index
# of WorkRows applied         =  1,210,838
Total # of WorkRows           = 51,639,908
# of NUSI change rows applied =          0
Total # of NUSI change rows   =          0     

The display for active parent sessions involved in the Apply Task of a MultiLoad operation provides the following information.

The column named... Contains the...
Statements total number of statements in the current session request.
Dispatched highest statement number dispatched to the AMPs.
Time time that the last step for the highest statement number was sent to the AMPs.
CPU Usage accumulated time in thousandths of a second that all AMPs spent processing the current request.
Accesses total number of segment access calls executed on all AMPs for the session request.

In addition, the display provides the following information.

Field Description
DataBase.Table Identifies the table on which the MultiLoad operation is running.
Action Describes the action being performed in the MultiLoad session.
# of WorkRows applied Displays the number of work rows processed in the apply phase.
Total # of WorkRows Displays the total number of rows processed.
# of NUSI change rows applied Number of nonunique secondary index rows processed in the apply phase.
Total # of NUSI change rows Total number of nonunique secondary index rows processed.

Application Phase Session for Delete Task Display

The following shows an example of the Query Session display for each table during a Delete Task, which includes the name of the database and table, the current action, the number of rows scanned, and the number of rows deleted.

State Details : Session involved in MLOAD utility
MLoad Phase : Application.
Task Running : Delete Task

Statements Dispatched Time     CPU Usage Accesses
---------- ---------- -------- --------- --------
         3          3 11:24:32    844679  310,987
               
DataBase.Table                = SPOOL_RES.WT_TDEM_PAIMT_MED
Action                        = Process Data
# of rows scanned             =  22,357
# of rows deleted             = 245,349
The values shown include both the primary and the fallback count.

The Delete Task display for a MultiLoad operation contains the same information as described for the Apply Task display except that it reports the number of rows processed and deleted rather than the rows processed by the apply phase.

Active Parent Session in an Acquisition Phase Display

The following shows an example display of an active parent session which is part of a MultiLoad operation.

State Details : Active Parent Session involved in MLOAD utility
MLoad Phase : Acquisition - Data Loading is in progress.
               
Statements Dispatched Time     CPU Usage Accesses Row Count
---------- ---------- -------- --------- -------- ---------
         1          1 09:23:45         8      166     9,854 

If you request detail information, Query Session reports child sessions as well. These are the descriptions of the phase:

  • Data Loading is in progress.
  • Data Loading is complete.

The display for active parent sessions involved in MultiLoad operations provides the following information.

The column named... Contains the...
Statements total number of statements in the current session request.
Dispatched highest statement number dispatched to the AMPs.
Time time that the last step for the highest statement number was sent to the AMPs.
CPU Usage accumulated time in thousandths of a second that all AMPs spent processing the current request.
Accesses total number of segment access calls executed on all AMPs for the session request.
Row Count total number of rows processed by the MultiLoad task.

Inactive Parent Session in an Acquisition Phase Display

The following shows an example display of an inactive parent session that is part of a MultiLoad operation.

State Details: InActive Parent Session involved in MLOAD Utility
MLoad Phase : Acquisition - Data Loading is complete.
               
CPU Usage Accesses Row Count
--------- -------- ---------
      130      654    45,673

These are the possible descriptions of the phase:

  • Data Loading is in progress.
  • Data Loading is complete.

The display for inactive parent sessions involved in a MultiLoad operation contains the following information.

The column named... Contains the...
CPU Usage accumulated time in thousandths of a second that all AMPs spent processing the current request.
Accesses total number of segment access calls executed on all AMPs for the session request.
Row Count total number of rows processed by the MultiLoad task.

Child Session in an Acquisition Phase Display

The following shows an example display for child sessions involved in a MultiLoad operation when the long form of the display is requested in response to the Detail Information Needed prompt.

State Details: CHILD session involved in MLOAD Acquisition Phase
               
Session # Request # State    TimeStamp Row Count
--------- --------- -------- --------- ---------
     1055      1632 Inactive 15:57:10      5,286
     1056      1635 Active   15:57:23        372

Child sessions involved in MultiLoad operations display these columns.

The column named... Contains the...
Session # session identifier.
Request # number of the request.
State state of the session, indicating whether the session is active or inactive.
TimeStamp time that is updated whenever a request is received from the host, a request is reinitiated to another AMP, or a response is sent to the host.
Row Count total number of rows loaded by the session.