Question

我有一个mysql查询，工作正常，但结果带有尾随和引导引号。这是如何：

SELECT 
     SUBSTRING_INDEX(SUBSTRING_INDEX(concat_values, ',',1), ',', -1) as first_col,
     SUBSTRING_INDEX(SUBSTRING_INDEX(concat_values, ',',2), ',', -1) as second_col,
     SUBSTRING_INDEX(SUBSTRING_INDEX(concat_values, ',',3), ',', -1) as third_col,
     SUBSTRING_INDEX(SUBSTRING_INDEX(concat_values, ',',4), ',', -1) as fourth_col

FROM (
    select 
     SELECT GROUP_CONCAT(column_name) as concat_values
    FROM my_table t1
    GROUP BY (uid) 

    ) t;

结果如下：

 Column1             Column2                  Column3       

["Result_1"]        ["Result_2"]             ["Result_3"]

我想修剪括号（[]）和引号（＆＃34;＆＃34;），以便结果显示为＆＃39; Result_1＆＃39;。已尝试使用TRIM(BOTH)，但我收到语法错误。

我最好如何修剪它？

Answer 1

这将有效：

    $str = '["Result_1"]';
    echo trim($str, '"');

    $str = '["Result_1"]';
    echo trim($str, '[');

    $str = '["Result_1"]';
    echo trim($str, ']');

Answer 2

这可以解决你在mysql中的问题

SELECT TRIM(BOTH '"' FROM TRIM(TRAILING ']' FROM TRIM(LEADING '[' FROM '["test"]')))

由于性能方面的考虑，我更喜欢修剪应用程序中的字符串。

修改

以下是如何为sql添加修剪

SELECT 
    TRIM(BOTH '"' FROM TRIM(TRAILING ']' FROM TRIM(LEADING '[' FROM SUBSTRING_INDEX(SUBSTRING_INDEX(concat_values, ',',1), ',', -1))))  AS first_col,
    TRIM(BOTH '"' FROM TRIM(TRAILING ']' FROM TRIM(LEADING '[' FROM SUBSTRING_INDEX(SUBSTRING_INDEX(concat_values, ',',2), ',', -1))))  AS second_col,
    TRIM(BOTH '"' FROM TRIM(TRAILING ']' FROM TRIM(LEADING '[' FROM SUBSTRING_INDEX(SUBSTRING_INDEX(concat_values, ',',3), ',', -1))))  AS third_col,
    TRIM(BOTH '"' FROM TRIM(TRAILING ']' FROM TRIM(LEADING '[' FROM SUBSTRING_INDEX(SUBSTRING_INDEX(concat_values, ',',4), ',', -1))))  AS fourth_col
FROM (
select 
 SELECT GROUP_CONCAT(column_name) as concat_values
FROM my_table t1
GROUP BY (uid) 

) t;

TRIM字符串连接值

2 个答案:

修改