mysql essays practice

The total number of statistics: select count (*) Number as from table name;
specify the query: Query student number is 2011001003 participants final score in the score table: SELECT SUM (score) FROM stu WHERE xuehao = '2011001003';
Query highest score , the lowest score, average score: SELECT MAX (score) AS highest score, mIN (score) AS lowest score, AVG (score) AS average FROM table;