Question

表格中有以下字符串：

step1.cards.choice_step_1
step1.cards.choice_step_2

step2.cards.choice_step_1
step2.cards.choice_step_2

我会使用该模式替换所有字符串中的空字符：

^step([0-9]|[1-9][0-9]).cards.choice_step_1$
^step([0-9]|[1-9][0-9]).cards.choice_step_2$

在MySQL中可以这样做吗？

最后我会得到结果：

修改

select regex_replace('[^0-9]','','step1.cards.choice_step_1');

回复我

请帮助您了解以下数据的正确模式：

sometext.step1
sometext.step1.cards.choice_step_1
sometext.step1.cards.choice_step_2
sometext.step1.desire

sometext.step2
sometext.step2.cards.choice_step_1
sometext.step2.cards.choice_step_2
sometext.step2.desire

获得以下结果：

step1
step1
step1
step1

step2
step2
step2
step2

Answer 1

您可以尝试这样的事情：

create table test (field1 varchar(100));
select * from test;
+------------------------------------+
| field1                             |
+------------------------------------+
| sometext.step1                     |
| sometext.step1.cards.choice_step_1 |
| sometext.step1.cards.choice_step_2 |
| sometext.step1.desire              |
| sometext.step2                     |
| sometext.step2.cards.choice_step_1 |
| sometext.step2.cards.choice_step_2 |
| sometext.step2.desire              |
| step1                              |
+------------------------------------+

查询：

select 
    field1,

    -- find position of step
    position('step' in field1) as step,

    -- find position of dot AFTER step is found
    position('.' in 
            substr(field1, position('step' in field1), length(field1))) 
            + position('step' in field1) as dot,

    -- if position of 'step' --and-- position of 'step' + position of 'dot' is 1
    --    that means: step is at position 1 and dot is not found, display field as is
    -- if position of 'step' --and-- position of 'step' + position of 'dot' are equal
    --    that means: dot is not found. Grab everything from step onwards
    -- if position of 'step' --and-- position of 'step' + position of 'dot' are **NOT** equal
    -- grab everything from where step was found thruogh just before dot was found
    case
    when position('step' in field1) = 1 
         and 
         position('.' in substr(field1, position('step' in field1), length(field1))) 
         + position('step' in field1) = 1 
         then 
            field1
    when position('step' in field1) = 
        position('.' in substr(field1, position('step' in field1), length(field1))) 
        + position('step' in field1) 
        then 
            substr(field1, position('step' in field1), length(field1))
    else 
        substr(field1, 
            position('step' in field1), 
            position('.' in substr(field1, position('step' in field1), length(field1)))-1
        )
    end as ans  

from test;

结果：

+------------------------------------+------+------+-------+
| field1                             | step | dot  | ans   |
+------------------------------------+------+------+-------+
| sometext.step1                     |   10 |   10 | step1 |
| sometext.step1.cards.choice_step_1 |   10 |   16 | step1 |
| sometext.step1.cards.choice_step_2 |   10 |   16 | step1 |
| sometext.step1.desire              |   10 |   16 | step1 |
| sometext.step2                     |   10 |   10 | step2 |
| sometext.step2.cards.choice_step_1 |   10 |   16 | step2 |
| sometext.step2.cards.choice_step_2 |   10 |   16 | step2 |
| sometext.step2.desire              |   10 |   16 | step2 |
| step1                              |    1 |    1 | step1 |
+------------------------------------+------+------+-------+

注意包含所需数据的最后一个字段。请随意根据您的需要进行调整。

mysql定期用空char替换字符

1 个答案: