[SOLVED] IBX uninitialised parameter.
lazarus / 16-Databases

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iru · 2019-09-24 05:34

Gentlefolk,

Environment: Linux Mint 19.2, Laz 2.02, IBX 2.3.2, Firebird 3.0.....

On the open of a IBX.IBDataSet with the SelectSQL property set to

'Select A.EVENTNUM, A.EVENTGENDER, A.EVENTTYPE, ......... From E
VENTDATA A where A.EVENTCOMPETITION = :EVENTCOMPETITION and
A.EVENTTYPE = :EVENTTYPE order....... ';

an exception occurs.

   SQL Param No. 1 (EVENTTYPE) is uninitialsed.

EVENTTYPE is varchar(3). All records in the table 'A' have EVENTTYPE
with a non NUL value.

No parameters are set on the IBX.IBDataSet.

An open on IBX.IBDataSet with the SelectSQL property set to

'Select A.EVENTNUM, A.EVENTGENDER, A.EVENTTYPE,....... From EVENTDATA
A where A.EVENTCOMPETITION = :EVENTCOMPETITION order.........';

works correctly with all records matching EVENTCOMPETITION displayed
in a grid.

Any help/ideas/suggestions appreciated, Ian.

I reviewed the above and it prompted me to check some semi forgotten
'brilliant' code in the IBX.IBDataSetBeforeOpen routine.

Problem solved, Ian.

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tonyw · 2019-09-24 08:56

Have you given a value to the parameter ":EVENTTYPE"? The exception
suggests not.

A common way to set the initial value is to do this in the dataset's
"BeforeOpen" event hander. For example:

procedure TForm1.MyDataSetBeforeOpen(DataSet: TDataSet);
begin
  (Dataset as TIBDataSet).ParamByName('EVENTTYPE').AsString := ''xxx';
end;

When the select query is executed, it will then return all rows with
column "EVENTTYPE" that have the value 'xxx'

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Cityalex · 2019-10-11 03:10

It would be good if we could work together on issues related to good
matters. Like this again in the future