Data Control Session vs Aux Session

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Teradata Employee

Data Control Session vs Aux Session

What is the difference between Control session and Aux session in terms of utilites ?

 

Can they both be aborted ? Can we see both of them in DBC.LogonOffV ?


Accepted Solutions
Teradata Employee

Re: Data Control Session vs Aux Session

Both Control and Aux sessions are normal SQL sessions, so requests from them can be logged via DBQL if you want to see what they do. The Control session obtains the LSN and initiates the actual utility processing. The Aux session handles certain supporting setup / cleanup activities.

 

All the sessions, including the parallel "special" sessions, are visible in DBC.LogOnOffV. You can abort any of the sessions individually, but normally you only need to abort the Control session to kill the job. 

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Teradata Employee

Re: Data Control Session vs Aux Session

Both Control and Aux sessions are normal SQL sessions, so requests from them can be logged via DBQL if you want to see what they do. The Control session obtains the LSN and initiates the actual utility processing. The Aux session handles certain supporting setup / cleanup activities.

 

All the sessions, including the parallel "special" sessions, are visible in DBC.LogOnOffV. You can abort any of the sessions individually, but normally you only need to abort the Control session to kill the job. 

Teradata Employee

Re: Data Control Session vs Aux Session

Hi Fred,

 

Thanks for the information.

 

What will happend if we abort any aux session, will it abort the whole load job too or is it the aborting of the control session only which would eventually abort the whole load job ?

Teradata Employee

Re: Data Control Session vs Aux Session

Aborting the Aux session will cause the job to fail eventually (but perhaps not immediately).

Teradata Employee

Re: Data Control Session vs Aux Session

Thanks for all the information Fred.