Question for mysql

can this code lag server because he is starting every 1 second in timer?:

pawn Code:

new Result:total3 = sql_query(mysql, "SELECT * FROM `Players` WHERE `Online`='1'");

sql_store_result(total3);

new ttotal3 = sql_num_rows(total3);

sql_free_result(total3);

that code is used to count for online players.