Question

oracle 取当天日期减一天 应该如何写

oracle 取当天日期减一比如今天是20100406 语句运行后的结果是20100405 天 应该如何写

Answer 1

1、创建测试表，

create table test_sysdate(v_date date);

2、插入测试数据

insert into test_sysdate values(sysdate);

insert into test_sysdate values(sysdate-1);

insert into test_sysdate values(sysdate-1.1);

insert into test_sysdate values(sysdate-1.2);

insert into test_sysdate values(sysdate-2);

insert into test_sysdate values(sysdate-3);

3、查询表中所有记录数，select t.*, rowid from test_sysdate t，

4、编写sql，查询日期为前一天的记录，select t.*, rowid from test_sysdate t where to_char(v_date,'yyyymmdd') = to_char(sysdate-1,'yyyymmdd')

Answer 2

1、创建测试表，

create table test_sysdate(v_date date);

2、插入测试数据

insert into test_sysdate values(sysdate);

insert into test_sysdate values(sysdate-1);

insert into test_sysdate values(sysdate-1.1);

insert into test_sysdate values(sysdate-1.2);

insert into test_sysdate values(sysdate-2);

insert into test_sysdate values(sysdate-3);

3、查询表中所有记录数，select t.*, rowid from test_sysdate t，

4、编写sql，查询日期为前一天的记录，select t.*, rowid from test_sysdate t where to_char(v_date,'yyyymmdd') = to_char(sysdate-1,'yyyymmdd')

Answer 3

select to_char(sysdate-1,'yyyymmdd') from dual;
select trunc(sysdate)-1 from dual;
这些都是OK的，我亲自试过

Answer 4

如果是只要取到天,那就是:
select to_char(sysdate-1,'yyyymmdd') from dual;

Answer 5

select to_char(to_date('20100406')-1,'yyyymmdd') from dual