`SQLFiddle Demo`

Question

有表格：

create table test(a int,b varchar(1000));

insert into test(a,b)
values(1,'1*0*6|2*0*4|3*0*2|4*0*1'),(2,'3*0*6|7*0*4|3*8*2)

希望从此获得选择：

a  b1  b2  b3
1, 1 , 0 , 6
1, 2,  0 , 4
1, 3,  0 , 2
1, 4,  0 , 1
2, 3,  0 , 6
2, 7,  0 , 4
2, 3,  8 , 2

怎么做？

Answer 1

<强> POSTGRESQL

select a, b[1], b[2], b[3]
from (
    select a, regexp_split_to_array(b, '*') from test
) as dt(b)

<强> MYSQL

SELECT 
a,
SUBSTRING_INDEX(b,'*', 1) as b1,
SUBSTRING_INDEX(SUBSTRING_INDEX(b,'*', 2), '*', -1) as b2,
SUBSTRING_INDEX(SUBSTRING_INDEX(b,'*', 3), '*', -1) as b3
from test

Answer 2

这不是一种非常有效的方法，但对于预期的输出，你可以尝试一下

`SQLFiddle Demo`

select a, 
  SUBSTRING_INDEX(b, '*', 1) as b1, 
  SUBSTRING_INDEX(SUBSTRING_INDEX(b, '*', 2),'*',-1) as b2,
  SUBSTRING_INDEX(SUBSTRING_INDEX(SUBSTRING_INDEX(b, '*', 3),'*',-1),'|',1) as b3 
from test

Answer 3

我使用此脚本将|的字符串解析为行http://kedar.nitty-witty.com/blog/wp-content/uploads/2009/12/split_string.sql。在我只有一个分隔符*的行后，我将其拆分：

call split_string()
SELECT
id,
SUBSTRING_INDEX(splitted_column,'*', 1) as b1,
SUBSTRING_INDEX(SUBSTRING_INDEX(splitted_column,'*', 2), '*', -1) as b2,
SUBSTRING_INDEX(SUBSTRING_INDEX(splitted_column,'*', 3), '*', -1) as b3
from my_splits

拆分多个字符的字符串

3 个答案:

`SQLFiddle Demo`