MySQL在行前选择 [英] MySQL select before after row

问题描述

这是示例表:

Column             | 1st record | 2nd record | 3rd record | 4th record | etc<br />
id (primary)       | 1          | 5          | 8          | 12         | etc<br />
name               | name 1     | name 2     | name 3     | name 4     | etc<br />
date               | date 1     | date 2     | date 3     | date 4     | etc<br />
callValue (unique) | val1       | val2       | val3       | val4       | etc

我选择一行作为要显示的数据(例如:具有callValue的行:val3).但是我找不到解决方案:
我需要选择上一行和下一行.因此，在此示例中，我需要从行vallValue:val4和callValue:val2或id:5和id:12中获取数据.

I select one row that is the data to show (for example: row with callValue: val3). But I cannot find a solution for this:
I need to select previous and next row. So, in this example, I need to get data from rows vallValue: val4 and callValue: val2, or id: 5 and id: 12.

使用id = id +-1不能完成此操作，因为由于删除行，id不必是连续的.

It cannot be done with id=id+-1 because id doesn't have to be continuous because of deleting rows.

推荐答案

尝试一下:

select * from test where callValue = 'val3'  
union all  
(select * from test where callValue < 'val3' order by id desc limit 1) 
union all  
(select * from test where callValue > 'val3' order by id asc limit 1) 

或

select * from test where id = 8
union all  
(select * from test where id < 8 order by id desc limit 1) 
union all  
(select * from test where id > 8 order by id asc limit 1) 

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