MonitorSQLCurrentStep Function | Application Programming Reference | Vantage - 17.10 - MonitorSQLCurrentStep - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - Application Programming Reference

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1090-171K
Language
English (United States)

Returns data about the step being executed of the currently running request for the specified host, session, and vproc.

Syntax

REPLACE FUNCTION SYSLIB.MonitorSQLCurrentStep (
  HostIdIn SMALLINT,
  SessionNoIn INTEGER,
  RunVprocNo SMALLINT
) RETURNS TABLE (
    HostId SMALLINT,
    SessionNo INTEGER,
    DynamicPlan  SMALLINT
    PartialSteps SMALLINT,
    NumOfSteps SMALLINT,
    CurLvl1StepNo SMALLINT,
    CurLvl2StepNo SMALLINT
    ZoneID INTEGER,
    SPName VARCHAR(128) CHARACTER SET UNICODE,
    SPDBName VARCHAR(128) CHARACTER SET UNICODE
    DefaultDBName VARCHAR(128) CHARACTER SET UNICODE
  )
  ...
;

Syntax Elements

HostIdIn
Logical ID of a host (or client) with sessions logged on.
A value of -1 indicates all hosts.
SessionNoIn
Session number of the SQL to monitor.
RunVprocNo
PE vproc number where the session runs.
HostId
Logical host ID associated with a PE or session. For a PE, HostId identifies one of the hosts or LANs associated with the described PE. For a session, the combination of a host ID and a session number uniquely identifies a user session on the system.
This value is NULL for AMPs. A value of zero represents the Supervisor window.
SessionNo
Number of the current session. Together with a given host ID, a session number uniquely identifies a session on the database system. This value is assigned by the host (or client) at logon time.
DynamicPlan
Plan type:
  • 0 = Static plan
  • 1 = Dynamic plan
For more information on static and dynamic explanations of a request, see the EXPLAIN request modifier in Teradata Vantage™ - SQL Data Manipulation Language, B035-1146 or Teradata Vantage™ - SQL Request and Transaction Processing, B035-1142.
PartialSteps
Possible values:
  • 0 = All steps are returned
  • 1 = Partial plan or no plan is returned

    If a partial plan is returned, this indicates the steps for the final plan fragment of the dynamic explanation of the request has not yet been generated.

    If no plan is returned, this indicates the request has been throttled and is in the delay queue.

A value 1 cannot occur for a static plan.
For more information on static and dynamic explanations of a request, see Teradata Vantage™ - SQL Data Manipulation Language, B035-1146 or Teradata Vantage™ - SQL Request and Transaction Processing, B035-1142.
NumOfSteps
Number of steps in the description text in the third statement of the response.
Plan DynamicPlan Field Value PartialSteps Field Value NumOfSteps
Static 0   Number of steps for plan.
Complete dynamic 1 0 Number of steps for plan.
Partial dynamic 1 1 Number of steps generated.
If a request with a partial dynamic plan has been throttled and is in the delay queue (that is, no rows are returned in response to the third statement), NumOfSteps is zero.
For more information, see the MONITOR SQL DynamicPlan and PartialSteps fields.
CurLvl1StepNo
Number of the currently executing level 1 step. If parallel steps are executing, it is the number of the lowest executing step.
If this is a request with a dynamic plan that has been throttled and is in the delay queue (for example, when the NumOfSteps field value is zero and both the DynamicPlan are PartialSteps field values are 1), the CurLvl1StepNo field value is zero.
CurLvl2StepNo
Number of the currently executing step. If parallel steps are executing, it is the number of the highest executing step. If only one step is executing, CurLvl1StepNo and CurLvl2StepNo are identical.
If this is a request with a dynamic plan that has been throttled and is in the delay queue (for example, when the NumOfSteps field value is zero and both the DynamicPlan are PartialSteps field values are 1), the CurLvl2StepNo field value is 1.
If only one step is executing, CurLvl1StepNo and CurLvl2StepNo are identical.
ZoneId
The unique identifier of the zone.
SPName
The outer stored procedure name, if a stored procedure is being executed.
NULL is returned in indicator mode if no stored procedure is being executed.
SPDName
This is the owner database name of the outer stored procedure if a stored procedure is being executed.
NULL is returned in indicator mode if no stored procedure is being executed.
DefaultDBName
This field returns the default database name of the session at the start of the non-stored procedure request. For stored procedures, it returns the default database name of the session when the stored procedure was compiled.

Usage Notes

This table function is only supported in Constant Mode.

If MONITOR SQL processing is not completed within the timeout interval, then an error is returned to the client application. When a MONITOR SQL request is timed out, the processing continues internally to its completion. If the client application submits a new MONITOR SQL request for the same timed out target session while the previous timed out one is still being processed, then an error is returned. The timeout interval can be set in the DBS Control field, PMPC_TimeoutSecs. The default timeout interval is 60 seconds. If the PMPC_TimeoutSecs field is set to zero, the MONITOR SQL timeout request will be disabled and no timeout will occur. For more information on the PMPC_TimeoutSecs field, see Teradata Vantage™ - Database Utilities, B035-1102.

The MonitorSQLCurrentStep function provides similar functionality to the PMPC MONITOR SQL request. For information about this interface, see MONITOR SQL.

Example: Using MonitorSQLCurrentStep

select * from table (monitorsqlcurrentstep(1,1472,30718)) as t1;

*** Query completed. One row found. 11 columns returned.
*** Total elapsed time was 1 second.

       HostId      1
    SessionNo        1472
  DynamicPlan      0
PartialSteps      0
   NumOfSteps     13
CurLvl1StepNo     10
CurLvl2StepNo     10
       ZoneId           0
       SPName
     SPDBName
DefaultDBName TESTUSER