我在创建视图时,用到了union all,结果出现了'未明确定义列'的错误,注意我的所有列名都没有错误,我一共用了3个union all,如果执行任意两个都没有问题,执行3个union all 就出现了上面的问题,不知道大家明白我的意思没有,举例:
create or replace A
as
select fieldname from b where sw1
union all
select fieldname from b where sw2
union all
select fieldname from b where sw3
union all
select fieldname from b where sw4如果我任意执行其中的两个union all,一点问题也没有
不知道大家遇到过这样的问题没有,望指点一二!
急,急,急!
create or replace A
as
select fieldname from b where sw1
union all
select fieldname from b where sw2
union all
select fieldname from b where sw3
union all
select fieldname from b where sw4如果我任意执行其中的两个union all,一点问题也没有
不知道大家遇到过这样的问题没有,望指点一二!
急,急,急!
as
这里少了关键字了吧?
create or replace view a
as
as
select fieldname f from b where sw1
union all
select fieldname f from b where sw2
union all
select fieldname f from b where sw3
union all
select fieldname f from b where sw4都加上别名试试
create view A
as
select * from (
select fieldname from b where sw1
union all
select fieldname from b where sw2
union all
select fieldname from b where sw3
union all
select fieldname from b where sw4
) x
union all
select fieldname from b where sw2
union all
select fieldname from b where sw3
union all
select fieldname from b where sw4
这部分很复杂,我只是简单的写成上面的格式罢了.