Mysql 按列列出的SQL计数出现次数
经过一些研究,我还没有找到我需要的,我想我会在这里问。我目前正在尝试开发一个应用程序的高级搜索模式,我的任务被卡住了。也许你能帮我。假设我有下表:Mysql 按列列出的SQL计数出现次数,mysql,sql,count,sql-like,Mysql,Sql,Count,Sql Like,经过一些研究,我还没有找到我需要的,我想我会在这里问。我目前正在尝试开发一个应用程序的高级搜索模式,我的任务被卡住了。也许你能帮我。假设我有下表: ID | Name | Surname 1 | John | Mim 2 | Johnny | Crazy 3 | Mike | Something 4 | Milk | Milk 5 | Peter | IDontknow 6 | Mitch | SomeName 然后在我的前端,有一个输入字段。该字
ID | Name | Surname
1 | John | Mim
2 | Johnny | Crazy
3 | Mike | Something
4 | Milk | Milk
5 | Peter | IDontknow
6 | Mitch | SomeName
然后在我的前端,有一个输入字段。该字段的输入将以这种方式通过查询:
SELECT name, surname FROM people WHERE name LIKE 'input%' OR surname LIKE 'input%'
现在假设我的输入是“Mi”,那么在“name”列中有3列匹配,在姓氏中有2列匹配。这就是我要找的
输出以下内容的计数:
Column | Count
Name | 3
Surname | 2
有没有一种方法可以在一个查询中实现这一点
到目前为止我所尝试的:实际上,我在数据库中的localhost上创建了上面的表,并尝试了不同的查询。尝试使用
选择count(姓名)、count(姓氏)
,但这两个计数都将输出3。所以我甚至不确定这是否只在一个查询中可行。使用union all
SELECT 'name' as col, count(name) as cnt FROM people WHERE name LIKE 'input%'
union all
SELECT 'surname', count(surname) FROM people WHERE surname LIKE 'input%'
创建自定义组时使用case
SELECT (case when name LIKE 'input%' then 'name'
else 'surname' end) as Column, count(*) as cnt
FROM people WHERE name LIKE 'input%' OR surname LIKE 'input%'
group by Column
在Mysql中,布尔值被计算为1或0,因此您可以这样做:
select 'Name' Column, sum(name LIKE 'input%') Count from people
union all
select 'Surname', sum(surname LIKE 'input%') from people
对于Mysql 8.0+您可以避免使用CTE对表进行双重扫描:
with cte as (
select
sum(name LIKE 'input%') namecounter,
sum(surname LIKE 'input%') surnamecounter
from people
)
select 'Name' Column, namecounter Count from cte
union all
select 'Surname', surnamecounter from cte
试试这个:
SELECT "Name" as Column, count(*) as Count FROM people WHERE name LIKE 'mi%'
UNION
SELECT "Surname" as Column, count(*) as Count FROM people WHERE surname LIKE 'mi%'
不包含
人员表的联合[ALL]
的解决方案:
SELECT
CASE cj.x WHEN 1 THEN 'Name' ELSE 'Surname' END AS `Column`,
CASE cj.x
WHEN 1 THEN COUNT(CASE WHEN Name LIKE concat(@input, '%') THEN 1 end)
ELSE COUNT(CASE WHEN Surname LIKE concat(@input, '%') THEN 1 END)
END `Count`
FROM people CROSS JOIN (SELECT 1 AS x UNION ALL SELECT 2) AS cj
WHERE Name LIKE concat(@input, '%') OR Surname LIKE concat(@input, '%')
GROUP BY cj.x;
Mi的输出
输入:
| Column | Count |
+---------+-------+
| Name | 3 |
| Surname | 2 |
在线测试。我的朋友,你是真正的英雄。