FireDAC paramamania

[Mark Williams 14]

I am having difficulties with a parameterized query designed to be used repeatedly. It works first time but never a second.

 

The query is fairly complicated so I prepare it on app initialization for repeated use, but it works just once and returns an empty dataset on every other occasion (even with the same parameter).

 

If I reset the query text (FDQuery.SQL.Text := FDQuery.SQL.Text) it works as expected.

 

That rather defeats the purpose of preparing the query in advance. Is it the case that parameters cannot be used in repeated queries?

[Hans J. Ellingsgaard 21]

You need to close and open the query every time you change the parameter values, if it has a result set. 

[Mark Williams 14]

So simple! Thanks.