Subject Re: [IBO] Transaction confusion
Author Helen Borrie (TeamIBO)
At 10:05 AM 15-01-02 +1100, John Peterson wrote:
>Hi All,
>I have a fairly simple service application that inserts records into a table. The app uses TIB_CONNECTION and TIB_DSQL components in a Data Module to perform the insertion.

I agree with Geoff, you are probably getting these periodic Invalid Transaction Handle errors because your DSQL is sitting in the same transaction as something else that either committed or rolled the transaction back, so that, once in a while, there is no transaction when you expect one.

You don't seem to be doing any exception handling to cover that possibility and I think that, at the very least, you will have to test for InTransaction before attempting to execute your statement.

Another observation + a couple of questions:

>Code snippet:
> if not DM1.SQL.Prepared then DM1.SQL.Prepare;
> with DM1.SQL.Params do begin
> Columns[0].AsInteger := StrToInt(copy(Su9.Line[3],29,6)); //SIDO
> ......
> Columns[84].AsString := copy(Su9.Line[5],71,1); // Tyre Decal
> end;
> DM1.SQL.Execute;
> (
> "SIDO",
> .......
> )
> (
> ?SIDO,
> .......
> ?TyreDecal
> )

Assuming DM1 is the DSQL object:

if not DM1.Prepared then DM1.Prepare;
with DM1 do begin
Params[0].AsInteger := StrToInt(copy(Su9.Line[3],29,6)); //SIDO
Params[84].AsString := copy(Su9.Line[5],71,1); // Tyre Decal


The SQL property is a TStrings...but perhaps this was just mistyping in your mail program.

Second, why are you passing constants to Params? Are these data going into non-data-aware controls?


Helen Borrie (TeamIBO Support)

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