how can i know a field's fieldtype before call execute?

[c123321]

i write comm procedure
Excesql(sqltext:string;params: array of const);

ｏｒａｃｌｅ　１０Ｇ；ｕｎｉｄａｃ　4.1.3


procedure TForm1.ExecSql(sql:String;params: array of const);
begin
Self.UniSQL1.SQL.Text := sql;
Self.UniSQL1.Params[0].value := Random(7000);
ShowMessage(IntToStr(params[0].vType)+','+IntToStr(params[1].vType));
//the TDateTime Type be convert to VExtended, when uses the next row, it is ok, else it is error;
//but i can not know the params[1] is TDatatime Field,how can i know? or use other method?
//such as { array of varint} but varint can not pass TStream; i like this procedure is common procedure
Self.UniSQL1.Params[1].DataType := ftDateTime;
Self.UniSQL1.Params[1].value := params[0].VExtended^;
Self.UniSQL1.Params[2].value := params[1].VExtended^;
Self.UniSQL1.Execute;
end;

procedure TForm1.btn3Click(Sender: TObject);
var
dt: TDateTime;
sal: Double;
begin
Randomize;
dt := Now;
sal := dt;
ExecSql('INSERT INTO EMP(EMPNO,hiredate,sal) VALUES (:randnum,:ssdate,:sal)',[dt, sal]);
end;

[c123321]

i write comm procedure
Excesql(sqltext:string;params: array of const);

oracle 10G, unidac　4.1.3 unidac demo db;


procedure TForm1.ExecSql(sql:String;params: array of const);
begin
Self.UniSQL1.SQL.Text := sql;
// Self.UniSQL1.Parpare; can use this then the UniSQL1.Params be setted? this value can not;
Self.UniSQL1.Params[0].value := Random(7000);
ShowMessage(IntToStr(params[0].vType)+','+IntToStr(params[1].vType));
//the TDateTime Type be convert to VExtended, when uses the next row, it is ok, else it is error;
//but i can not know the params[1] is TDatatime Field,how can i know? or use other method? i think where i
//such as { array of varint} but varint can not pass TStream; i like this procedure is common procedure
Self.UniSQL1.Params[1].DataType := ftDateTime;
Self.UniSQL1.Params[1].value := params[0].VExtended^;
Self.UniSQL1.Params[2].value := params[1].VExtended^;
Self.UniSQL1.Execute;
end;

procedure TForm1.btn3Click(Sender: TObject);
var
dt: TDateTime;
sal: Double;
begin
Randomize;
dt := Now;
sal := dt;
ExecSql('INSERT INTO EMP(EMPNO,hiredate,sal) VALUES (:randnum,:ssdate,:sal)',[dt, sal]);
end;

[AlexP]

Hello,

We cannot define the parameter type created by a user, so we send the value that is set to the parameter (in our case, it is a number) to the server. You should either set the parameter type explicitly

UniSQL1.Params[1].DataType := ftDateTime;

or use casting when setting the parameter type

UniSQL1.Params[1].Value := VarToDateTime(params[0].VExtended^);

else, specify the type you bind

UniSQL1.Params[1].AsDateTime := params[0].VExtended^;

[c123321]

the import thing is that i don't know the type is datetime because i will write a common procedure, why the unisql1.prepare procdure can not set the parameter type ?

Hello,

We cannot define the parameter type created by a user, so we send the value that is set to the parameter (in our case, it is a number) to the server. You should either set the parameter type explicitly

UniSQL1.Params[1].DataType := ftDateTime;

or use casting when setting the parameter type

UniSQL1.Params[1].Value := VarToDateTime(params[0].VExtended^);

else, specify the type you bind

UniSQL1.Params[1].AsDateTime := params[0].VExtended^;

[AlexP]

Hello,

Automatic definition of user's parameters is not supported for Oracle, the parameter type will remain ffUnknown even after calling the Prepare method. One of the possible ways of realization of such universal method can be transfer of a parameters pair (value-type) to the method

Code: Select all

ExecSql('INSERT INTO EMP(EMPNO,hiredate,sal) VALUES (:randnum,:ssdate,:sal)',[dt, Integer(ftDateTime), sal, Integer(ftFloat)]);


  Self.UniSQL1.Params[1].DataType := TFieldType(params[1].VExtended);
  Self.UniSQL1.Params[1].value := params[0].VExtended^;
  Self.UniSQL1.Params[2].DataType := TFieldType(params[3].VExtended);;
  Self.UniSQL1.Params[2].value := params[2].VExtended^;

[c123321]

thinks, final solve is this:

ExecSql('INSERT INTO EMP(EMPNO,hiredate,sal) VALUES (:randnum,:ssdate,:sal)',[varfromdatetime(dt), sal]);

[AlexP]

Hello,

Glad to see that you solved the problem.
If you have any other questions, feel free to contact us.