1、增加 
(1)插入记录:
INSERT [INTO] tbl_name[( col_name )] {VALUES | VALUE}({expr | DEFAULT},...),(...),...

(2)可以使用子查询(SubQeury):
INSERT [INTO] tbl_name SET col_name={expr | DEFAULT},...

(3)将查询结果插入到指定数据表:
INSERT [INTO] tbl_name[(col_nmae,...)] SELECT ...

2、删除
DELETE FROM tbl_name [WHERE where_condition]

3、更新
UPDATE [LOW_PRIORITY] [IGNORE] table_reference SET col_name1={expr1 | DEFAULT }[, col_name1={expr1 | DEFAULT }]...[WHERE where_condition]

4、查询
SELECT select_expr [,select_expr]
[
FROM table_references
[ WHERE where_condition ]//条件表达式,支持函数或运算符
[ GROUP BY {col_name | position} [ASC | DESC], ... ] //查询结果分组
[ HAVING where _condition ]//分组条件
[ ORDER BY {col_name | expr | position} [ASC | DESC ], ... ]//查询结果排序
[ LIMIT {[offset,] row_count | row_count OFFSET offset} ] //限制查询结果返回的数量
]

*表示所有列
AS 赋予别名

写操作:INSERT  UPDATE  DELETE
读操作:SELECT