How can I assign a NULL value to TSQLDataSet parameter?

I tried to use this
. . .
SQLDataSet1.CommandText := 'insert into Arquivo (FldInt, FldStr, FldDate)
values (:FldInt, :FldStr, :FldDate)'
SQLDataSet1.ParamByName('FldInt').value := 15;
SQLDataSet1.ParamByName('FldStr').value := 'TEST';
SQLDataSet1.ParamByName('FldDate').value := NULL;             // Error here
. . .

With ADO this work, but with dbExpress a get this msg:
    No value for parameter FldDate

I already tried this:
  SQLDataSet1.ParamByName('FldDate').Clear;

--
Thanks in advance,
Alvaro L. S. Almeida

SQLDataSet1.ParamByName('FldDate').Clear;

--
Bill
(TeamB cannot answer questions received via email)

"Bill Todd (TeamB)" <bill.nos...@dbginc.com> wrote in message
news:3bd1e2c3$1_2@dnews...

If I try this I get the msg:  No value for parameter "FldDate"

I'm using D6.01 with IB6.01 and dbExpress (TSQLDataSet).

--
Alvaro L. S. Almeida

I am not sure what the source of that error is. Does the field allow nulls?

--
Bill
(TeamB cannot answer questions received via email)

Yes, the field allow nulls. I already tested with another field types, and
the error is the same (No value for parameter "XXX").

I'm using Delphi 6.01 Pro  with  INTERBASE 6.0.1

This is the table:
CREATE TABLE "TestTbl"
(  
  "FldInt"     INTEGER NOT NULL,
  "FldStr"     VARCHAR(50) CHARACTER SET WIN1252 COLLATE PXW_INTL850,
  "FldDate"  DATE
);

for insert, I'm using
  SQLDataSet1.CommandText := 'insert into TesTbl (FldInt, FldStr, FldDate) values (:FldInt, :FldStr, :FldDate)';

but I can't pass a NULL value to any parameter.

I already tested these:
  SQLDataSet1.ParamByName('FldDate').Clear;
  SQLDataSet1.ParamByName('FldDate').AsString := '';
  SQLDataSet1.ParamByName('FldDate').value := NULL;
  SQLDataSet1.ParamByName('FldDate').AsDate := NULL;
 . . .

Using IBX or ADO (with SqlServer), I can assign NULL to any parameter, but with dbExpress, I can't!

--
Alvaro L. S. Almeida

On Sat, 20 Oct 2001 17:53:57 -0300, "Alvaro L. S. Almeida"

Try the following

SQLDataset1.ParamByName('FldDate').asDate:=date;
SQLDataset1.ParamByName('FldDate').Clear;

(Syntax not tested) As I Remember from working with the BDE, one has
to set some additional Info for the Parameter and the Assignment of a
Dummy-Value takes care of that. Then clearing the Parameter sets it to
NULL, but keeps the other Parameters (like fieldtype and so on)

HTH
Georg

Great!
It works!

--
Thanks,
Alvaro L. S. Almeida
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