Question

我的表格如下：

id       jancuk        pijut
-------------------------------
1        20 * 4         
2         2 + 4         
3     3 - 1 + 2         
4        20 / 5

我想使用pijut列的结果更新列jancuk。这是否可以在oracle中使用查询？
因此，如果表已更新，那么表应如下所示：

id       jancuk        pijut
-------------------------------
1        20 * 4         80
2         2 + 4          6
3     3 - 1 + 2          4
4        20 / 5          4

请帮帮我。感谢。

Answer 1

您可以使用带动态SQL的函数来执行此操作 -

create or replace function calc_value(str in varchar2) return number is
 val_ number;
begin
    if str is null then
         return null;
    end if;
    execute immediate 'begin :val_ := '||str||'; end;' using out val_;
    return val_;
end;
/

，结果选择将是 -

with t as
(
select 1 as id, '        20 * 4 ' as jancuk from dual union all
select 2 as id, '         2 + 4 ' as jancuk from dual union all      
select 3 as id, '     3 - 1 + 2 ' as jancuk from dual union all       
select 4 as id, '        20 / 5 ' as jancuk from dual
)
select id, jancuk, calc_value(jancuk) as pijut
from t

Answer 2

尝试：

update tbl
set "pijut" = xmlquery(replace( "jancuk", '/', ' div ' ) returning content ).getNumberVal();

了解更多信息link

在Oracle中计算单列

2 个答案: