计数SQL语法计数(值)多个列

时间:2021-12-02 14:37:14

Hello im trying to learn about Count in sql, but i cant even count how many times a value is in a specific column

你好,我正在尝试学习sql中的Count,但我甚至无法计算一个值在特定列中的次数

My database structure is this. (table : natural)

我的数据库结构是这样的。(表:自然)

ID |  one |  two | three |

1  |   34 |  45  |  80  |
2  |   41 |  34  |  7   |
3  |   7  |  18  |  22  |
4  |   8  |  7   |  45  |

Im trying this

我尝试这

 $result=mysql_query("SELECT COUNT(one) AS total FROM natural
WHERE one=7")or die("Error: ".mysql_error());
$data=mysql_fetch_assoc($result);
echo $data['total'];

but even with just 1 column in count i cant get the result..

但即使只列了一列,我也得不到结果。

What i need is count how many times is a "value" (for example 7) in all the columns

我需要计算的是在所有列中有多少次“值”(例如7)!

like in this example value 7 = 3 total (multiple columns)

如本例中的值7 = 3 total(多列)

How can i make a sql like that.

我怎么能做出这样的sql呢?

EDIT: Trying this (where is my syntax problem?)

编辑:尝试这个(我的语法问题在哪里?)

$result=mysql_query("SELECT  COUNT(DISTINCT id) TotalCount FROM tblname WHERE 7 IN (one, two, three)")or die("Error: ".mysql_error());
$data=mysql_fetch_assoc($result);
echo $data['TotalCount'];

I SUCK, thanks for your answers, but i think my problems is with mysql_query () cause i always got a syntax problem, with all your answers and its obviously me.

谢谢你的回答,但我认为我的问题是mysql_query(),因为我总是有语法问题,所有的答案都是我的。

$result=mysql_query("SELECT (SUM(CASE WHEN   one = 7 THEN 1 ELSE 0 END) +
        SUM(CASE WHEN   two = 7 THEN 1 ELSE 0 END) +
        SUM(CASE WHEN three = 7 THEN 1 ELSE 0 END)) TotalCount
  FROM natural")or die("Error: ".mysql_error());
$data=mysql_fetch_assoc($result);
echo $data['TotalCount'];

To Fix this last code, just use one and two ... so on, and natural thats the correct syntax :D

要修改最后的代码,只需使用1和2……这就是正确的语法:D。

1 个解决方案

#1


7  

This one will give you the right answer even if values repeat across columns

即使值在列中重复,这个也会给你正确的答案。

SELECT (SUM(CASE WHEN   one = 7 THEN 1 ELSE 0 END) +
        SUM(CASE WHEN   two = 7 THEN 1 ELSE 0 END) +
        SUM(CASE WHEN three = 7 THEN 1 ELSE 0 END)) TotalCount
  FROM table1

SQLFiddle

SQLFiddle

If you have following data

如果你有以下数据。

| ID | ONE | TWO | THREE |
--------------------------
|  1 |  34 |  45 |    80 |
|  2 |  41 |   7 |     7 |
|  3 |   7 |  18 |    22 |
|  4 |   7 |   7 |    45 |

Output will be

输出将

| TOTALCOUNT |
--------------
|          5 |

#1


7  

This one will give you the right answer even if values repeat across columns

即使值在列中重复,这个也会给你正确的答案。

SELECT (SUM(CASE WHEN   one = 7 THEN 1 ELSE 0 END) +
        SUM(CASE WHEN   two = 7 THEN 1 ELSE 0 END) +
        SUM(CASE WHEN three = 7 THEN 1 ELSE 0 END)) TotalCount
  FROM table1

SQLFiddle

SQLFiddle

If you have following data

如果你有以下数据。

| ID | ONE | TWO | THREE |
--------------------------
|  1 |  34 |  45 |    80 |
|  2 |  41 |   7 |     7 |
|  3 |   7 |  18 |    22 |
|  4 |   7 |   7 |    45 |

Output will be

输出将

| TOTALCOUNT |
--------------
|          5 |