Locate() fails with a 'Variant conversion error', if you search for only one field and have this in a variant array.
This is a problem if you create the array to search for dynamically at runtime.
In the case, that you array would have only one entry, you have to pass the value itself:
Note:
This was observed under Delphi 3 with BDE 5 using InterBase and MS-SQL. I don't know if the problem occurs with later versions of Delphi. BDE version and dbms should not matter.
begin
..
MyArr := ..
FieldStr :=
..
case FieldCount of
0: // error
1: found := Table1.Locate(FieldStr, MyArr[0], []);
else found := Table1.Locate(FieldStr, MyArr, []);
end;
end.