1、创建测试表,
create table test_order(id number, value1 number, value2 number)
2、插入测试数据
insert into test_order values(1,1001,2001)
insert into test_order values(2,1002,2002)
insert into test_order values(3,1003,2003)
insert into test_order values(4,1004,2004)
insert into test_order values(5,1005,2005)
3、查询表中所有记录数,select t.*, rowid from test_order t,
4、编写sql,按value1字段做升序,按value2字段做降序,
select t.*,
row_number() over(order by value1) rn1,
row_number() over(order by value2 desc) rn12
from test_order t
SQL 语句中, asc是指定列按升序排列,desc则是指定列按降序排列。
排序子句语法:order by 列名 asc/desc
例表格:tt
1、按列n2的升序排列
select * from tt order by n2 asc2、按列n2的降序排列
select * from tt order by n2 desc3、复合排序,先按列n1升序排列,再按n2降序排列
select * from tt order by n1 asc,n2 descmySQL里desc和asc的意思desc是descend 降序意思
asc 是ascend 升序意思
sql = "select 表内容名from 数据库表名 Putout=true order by 读取的排序表名 asc"
例如
sql = "select * from user where Putout=true order by timedesc"//按最新时间来排序
sql = "select * from user where Putout=true order by timeasc" //按早时间来排序
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