Question

+-------+-----------+------------+
| id    | sequence  | text       |
+-------+-----------+------------+
| 12345 | 01        | Hello, my  | 
| 12345 | 02        | name is CJ | 
| 54321 | 01        | Good morn  | 
| 54321 | 02        | ing! Sup!  | 
+-------+-----------+------------+

我完全迷失了。这些行中有2条消息1）“你好，我的名字是CJ”和2）“早上好！Sup！”

如何通过ID和正确的顺序（序列）选择这两种消息？

所以结果将是

“你好，我的名字是CJ”

“早上好！Sup！”

Answer 1

尝试 GROUP_CONCAT

SELECT id,GROUP_CONCAT(text SEPARATOR ' ')
FROM tableA
GROUP BY id;

Answer 2

$scope.clicked = function(index){
 let currentOption=$scope.Persons[index].show;
 $scope.Persons.forEach(x=>x.show=false);
 $scope.Persons[index].show=!currentOption;
}

Answer 3

SELECT id,GROUP_CONCAT(text ORDER BY sequence  SEPARATOR ' ') AS messages
FROM table1
GROUP BY id;

<强>输出

id      messages
12345   Hello, my name is CJ
54321   Good morning! Sup!

<强>演示

http://sqlfiddle.com/#!9/f38d19/5

GROUP_CONCAT（）函数

MySQL GROUP_CONCAT（）函数返回一个连接的字符串来自组的非NULL值。

语法：

GROUP_CONCAT([DISTINCT] expr [,expr ...]
         [ORDER BY {unsigned_integer | col_name | expr}
             [ASC | DESC] [,col_name ...]]
         [SEPARATOR str_val])

mysql选择具有相同ID的行，并按另一列的顺序选择

3 个答案: