First Query:

myquery.SQL.Text := 'INSERT INTO mytable '+
 '(id,mytext,mydate)'+
 'VALUES '+
 '(LASTAUTOINC(''mytable'')+1,''some text'', CURRENT_TIMESTAMP)';
myQuery.ExecSQL;

Second Query:

myquery.SQL.Text := 'INSERT INTO mytable '+
 '(id,mytext,mydate)'+
 'VALUES '+
 '(LASTAUTOINC(''mytable'')+1,:mytext, CURRENT_TIMESTAMP)';
myQuery.ParamBynamemytextxt').AsString := 'my text';
myQuery.ExecSQL;