基本语句

select * from table

从表table中查询所有数据

select * from table where "列名" = "?"

从表table中查询列名等于？的数据

update table set "列名1" = "?1" where "列名2" = "?2"

将表table中列名2的等于?2时将列名1的数据改为?1

insert into table values(????)

插入数据

delete from table where "列名" = "?"

将表中列名等于?的数据删除

select concat(colum1,colum2) as name from table

将table中colum1,colum2合并为name并打印

train(colum)

去除colum数据的空格

order by colum1

根据colum1进行升序排序,可有多个参数

order by column desc

根据colum1进行降序排序

select * from table limit num

输出num条数据

select * from table limit num1,num2

从num1开始输出num2条数据，不包num1;

select * from table1 as a,table2 as b where a.colum1 = b.cloum2

关联打印，将表a表b中相关的数据打印出来