Question : Begin/Commit Nested Transactions in VFP/Sql Server environment

Hi Folks,

 In my VFP 8.0 app, when a user clicks on the MODIFY button, I want to lock the row right away (Pessimistic). I do not use a VFP transaction, but rather a sql server transaction as follows:

  *-- set sql server timeout to 5 seconds, begin the transaction, then select with two lock hints.
  lcSqlExec = "SET LOCK_TIMEOUT 5000 " + ;
            " BEGIN TRANSACTION " + ;
            " Select * From " + tabl_lock + "  WITH (UPDLOCK,ROWLOCK) " + " Where Pkey = " + lcPkey
           
  lnResult = SQLExec(gnConnection, lcSqlExec, 'c_TableLocked')


So far, this works fine. In other words, if I go to a QA Sql session (or another VFP session) and issue the same exact Select as above (same tabl_lock and lcPkey), it WILL time out.

Now...when the user finishes his modification he simply cliks the OK button. Behind the scenes I exec an Update stored procedure. Within that proc, I begin/commit a nested transaction as follows:
                ...
               SET @SqlStr = @SqlStr + ' WHERE ' + @pSqlWhere
            BEGIN TRANSACTION
                   EXEC sp_executeSql @SqlStr -- this runs the dynamic Update command
            COMMIT TRANSACTION
               .....

Now the confusing part is that after I exec this procedure, it appears that my first transaction has auto-commited. My first tran should still be open, no ?

I know this because I check the value of the sql server system var @@trancount before AND after I exec the Update stored proc :

    =SQLExec(gnConnection, "select @@trancount as transaction_count", 'c_TranCount')


Before I exec my stored proc, @@trancount shows 1 transaction. As soon as I exec the stored proc, @@trancount returns a zero. WHY ??? I should still be running within my original transaction that I started up above (when locking the row).

This doesn't allow me to cleanly COMMIT my first transaction via SqlExec() ....I don't understand why this happens...

thank you,
John

Answer : Begin/Commit Nested Transactions in VFP/Sql Server environment

Closed, no 125 points refunded.

modulo
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