Insert/Update/Delete using by SQL

Posted in Databases

This example uses COUNTRY.DB database of DBDEMOS standard alias. SQL is a power tool for working with database. This example shows 3 main operations with database (Insert, Update and Delete record).

// Insert record
procedure TForm1.Button1Click(Sender: TObject);
begin
  with Query1 do
  begin
    Active:=False;
    SQL.Clear;
    SQL.Add('Insert into country(NAME,CAPITAL,CONTINENT,AREA,POPULATION) 
               values(
                 ''A_My_Country'', 
                 ''A_My_Capital'', 
                 ''A_My_Continent'', 
                 1, 
                 1)');
    ExecSQL;
  end;
  Table1.Refresh;
end;

// Delete record
procedure TForm1.Button2Click(Sender: TObject);
begin
  with Query1 do
  begin
    Active:=False;
    SQL.Clear;
    SQL.Add('Delete from country where name=''A_My_Country''');
    ExecSQL;
  end;
  Table1.Refresh;
end;

//Update record
procedure TForm1.Button3Click(Sender: TObject);
begin
  with Query1 do
  begin
    Active:=False;
    SQL.Clear;
    SQL.Add('Update country set name=''A_Your_Country'' 
               where name=''A_My_Country''');
    ExecSQL;
  end;
  Table1.Refresh;
end;