mysql 语法

                                  -create database database_name; show databases;show tables;
                                 | -create table table_name(column_name1 column_type,column_name2 column_type); desc table_name;
                                 |
                                 | -drop table table_name;
DDL---------               |-drop -drop database database_name;
(数据定义语言)              |          
                                 | -alter table table_name ALTER_SPECIFICATION column_name column_definition [first/after column_name];;
                                 |-alter -alter table table_name rename new_table_name;

                                |-insert -insert into table_name (field1,field2,field3.....) values (value1,value2,value3....)
                                | -insert into table_name (field1,field2,field3.....) values (record1_value1,record1_value2,...record1_valuen),
                                | (record2_value1,record2_value2,...record2_valuen);
DML---------               |-update -update table_name set field1=value1,field2=value2... where condition;
（数据操作语言）          | -update table_name1,table_name2 set table_name1.field1=expr1,table_name2.field2=expr2 where condition;
                                |
                                |-delete -delete from table_name where condition;
                                | -delete t1,t2...from t1,t2 where condition;
                                |
                                |-select -select * from table_name where condition;
                                | -select * from table_name where condition order by field desc/asc;
                                | -select * from table_name limit(offset_start,row_count);
                                | -select field1,field2 fun_name from table_name /where where_contition/group by fieldn/with rollup/having where_contition;
                                | -select * from t1 union/union all select t2 union/union...;

                         |-grant select,insert on database_name.* to 'user_name'@'localhost' identified by '密码'
        DCL---------|
（数据控制语言）   |-revoke select,insert on database_name.* to 'user_name'@'localhost';