Question

我编写了一个mysql查询来使用nodejs api检索数据。一切正常，但我想改变数据格式。我的数据格式是：

"data": [
    {
        "Name": "faseeh tauheed,Muhammad  Saeed,Farhan Khan",
        "Email": "faseeh@gmail.com,saeed@gmail.com,farhan@gmail.com",
        "Contact": "923158414969,923132347067,923471220797",
        "Skill": "HTML",
        "Experience": "36,72,48"
    }
]

但我希望每个人的记录在一行中如下：

"faseeh tauheed", "faseeh@gmail.com", "923158414969", "HTML", "36"

我在数据中遇到歧义，所以我使用了MYSQL的GROUP_CONCAT（）方法。这是我的疑问：

SELECT GROUP_CONCAT(DISTINCT CONCAT(a.FirstName," ",a.LastName)) AS Name,
GROUP_CONCAT(DISTINCT b.Email) as Email, GROUP_CONCAT(DISTINCT a.Contact) as Contact,
GROUP_CONCAT(DISTINCT c.skillName) as Skill, GROUP_CONCAT(DISTINCT d.totalExperience) 
AS Experience from applicant_personal_info a JOIN applicant b ON a.ApplicantID = 
b.ApplicantID JOIN applicant_skills c ON a.ApplicantID = c.ApplicantID 
JOIN applicant_professional_info d ON a.ApplicantID = d.ApplicantID 
WHERE c.skillName = 'HTML'

Answer 1

最好不要连接任何数据。然后，您将拥有可以轻松使用的单独行。我也解散了FirstName和Name，因为稍后会更容易使用 - 但如果你真的需要，你可以保持这个连续

SELECT a.FirstName AS FirstName,
       a.LastName AS Name,    -- or CONCAT(a.FirstName," ",a.LastName) as Name 
       b.Email AS Email,
       a.Contact AS Contact,
       c.skillName AS Skill,
       d.totalExperience AS Experience
FROM applicant_personal_info a
JOIN applicant b ON a.ApplicantID = b.ApplicantID
JOIN applicant_skills c ON a.ApplicantID = c.ApplicantID
JOIN applicant_professional_info d ON a.ApplicantID = d.ApplicantID
WHERE c.skillName = 'HTML'

你会得到：

"data": [
    {
        "FirsName": "faseeh",
        "Name": "tauheed",
        "Email": "faseeh@gmail.com",
        "Contact": "923158414969",
        "Skill": "HTML",
        "Experience": "36"
    },
    {
        "FirstName": "Muhammad",
        "Name": "Saeed",
        "Email": "saeed@gmail.com",
        "Contact": "923132347067",
        "Skill": "HTML",
        "Experience": "72"
    },
    {
        "FirstName": "Farhan",
        "Name": "Khan",
        "Email": "farhan@gmail.com",
        "Contact": "923471220797",
        "Skill": "HTML",
        "Experience": "48"
    }
]

如果您只需要获取第一行数据，请在查询末尾添加以下行：

 LIMIT 1;

-

最后但并非最不重要的一点是，如果出于某种原因肯定需要使用这些CONCAT，您可以将这些数据与节点分开。你的SQL语句已经足够复杂了，即使你通过过度复杂的方式正确地完成它，如果需要的话，在几个月内维护和改变将是一场噩梦。

- 编辑：

SELECT CONCAT('"',
         a.FirstName , '", "',
         a.LastName , '", "',
         b.Email , '", "',
         a.Contact , '", "',
         c.skillName , '", "',
         d.totalExperience , '"') as user
FROM applicant_personal_info a
JOIN applicant b ON a.ApplicantID = b.ApplicantID
JOIN applicant_skills c ON a.ApplicantID = c.ApplicantID
JOIN applicant_professional_info d ON a.ApplicantID = d.ApplicantID
WHERE c.skillName = 'HTML'

应该给：

"data": [
    {
        "User": "\"faseeh\", \"tauheed\", \"faseeh@gmail.com\", \"923158414969", \"HTML\", \"36\""
    },
    {
... with all the other users in the same format
]

\＆＃34;这里仅代表双引号可能会在你的json中转义的事实

MYSQL查询格式

1 个答案: