Support For Sqlcancel() With The Drda Listener And Db2 For I With The Db2 Wire Protocol Driver

[mwalton@microstrategy.com]

Please implement support of SQLCancel() with the DB2 Wire Protocol driver when connected to DB2 for i database. The current driver does not send or does not support SQLCancel() with this DB type and so long running queries do not get cancelled. The historical reason is that in the past the DRDA listener did not support SQLCancel but that was rectified in the DB2 for i 6.1 release (see below for more details). Document title: IBM i 6.1 Technical Overview Excerpt: https://books.google.com/books?id=2FfAAgAAQBAJ&pg=PA97&lpg=PA97&dq=drda+sqlcancel&source=bl&ots=gNFy3F-yDt&sig=dpH2nzdPUgcHYJd 6Sk6Ja3H4ooM&hl=en&sa=X&ved=0CEsQ6AEwCGoVChMIo8ScubXYyAIVi6seCh2rGQsy#v=onepage&q=drda%20sqlcancel&f=false Statement: "DRDA in IBM 6.1 supports the the SQLCancel() statement." As it stands now, any SQL statement that is submitted by the client using the DB2 Wire Protocol driver will run until completion regardless of the call by the application to cancel the execution (SQLCancel()). This means that the only way to kill long running and potentially resource draining SQL is to have the DB2 for i administrator to kill it from the admin console. As a point of comparison, the IBM Native ODBC Driver for iSeries does not have this problem. It can successfully pass the SQLCancel() request to the DB server and the statement will stop executing.

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