将对象数组分解为用于数据库存储的单独变量（React、express、sql server）
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【中文标题】将对象数组分解为用于数据库存储的单独变量（React、express、sql server）【英文标题】：Breaking down array of objects into separate variables for database storage (React,express,sql server) 【发布时间】：2020-02-18 09:11:10 【问题描述】：我的 reactjs 应用程序中有一个存储的对象数组，当控制台记录时看起来像这样。
0: answer: "yes↵", question: "Is the keyboard separate from the screen?", state: "Declined with soloution defined"
1: answer: "yes", question: "Does the keyboard tilt?", state: "Accepted"
2: answer: "Question declined But not a problem", question: "Is it possible to find a comfortable typing postion?", state: "Accepted"
3: answer: "yes", question: "Do you have a good keyboard technique?", state: "Accepted"
4: answer: "Question declined But not a problem", question: "Are the characters on the keyboard clear and readable?", state: "Accepted"
5: answer: "sgdfgdfgdf", question: "Is your mouse or other pointing device suitable to the task you're using it for?", state: "problem specified"
6: answer: "yes", question: "Is the mouse (or other pointing device) located sufficently close to you? ", state: "Accepted"
7: answer: "sdfsdfsdfsd", question: "Is there support for your wrist and forearm when using the mouse(or other pointing device)", state: "Declined with soloution defined"
8: answer: "yes", question: "Does the mouse (or other pointing device) work smoothly at a speed that suits you?", state: "Accepted"
9: answer: "asdasdas", question: "Can you easily adjust the software settings for speed and accuracy of the pointer?", state: "Declined with soloution defined"
10: answer: "asdasdads", question: "Are the characters on your screen clear and readable?", state: "problem specified"
11: answer: "yes", question: "Is the text size on your screen confortable to read?", state: "Accepted"
12: answer: "asdasdasd", question: "Is the image on your screen free from flicker and jitter?", state: "Declined with soloution defined"
13: answer: "asdasdasd", question: "Is your screen's specification suitable for its intended use?", state: "problem specified"
14: answer: "yes", question: "Is the brightness and/or contrast on your screen adjustable?", state: "Accepted"
这包括答案、问题和状态（已回答问题的状态不是反应组件中的状态）
我想做的是将这些传递给表达，以便我可以使用 npm 包 mssql 将它们上传到我的 SQL 数据库中。但是，由于这些都存储在数组中，我不确定如何将它们拆分。
理想情况下，我希望将整个对象传递给 SQL，然后将整个对象存储在数据库中，例如（伪代码）
insert into table where answer = answer and question = question and state = state
基本上要将此与 SQL 一起使用，我将如何分解这些以与我的后端一起使用，或者我可以使用特定的 SQL 存储过程传递整个对象。
create procedure StoreAnswers
@answer_values
as
INSERT INTO QuestionResponses
(RUId, QuestionId, Date, QuestionWhenAnswered, QuestionResponse, Accepted, AssignedWorkStation )
VALUES
$answer_values
编辑
存储过程
create procedure StoreAnswers(@Results varchar(max))
as begin
insert into QuestionResponses(QuestionResponse, QuestionWhenAnswered, State)
select substring(value, charindex('answer: "', value) + 10, charindex('", ', value, charindex('answer: "', value) + 10) - charindex('answer: "', value) - 10) as answer,
substring(value, charindex('question: "', value) + 11, charindex('", ', value, charindex('question: "', value) + 11) - charindex('question: "', value) - 11) as question,
substring(value, charindex('state: "', value) + 8, charindex('"', value, charindex('state: "', value) + 8) - charindex('state: "', value) - 8) as state
from string_split(@Results, char(10))
end;
如何从 express npm 传递到 sql 查询
app.post("/post-question-answers", async (req, res) =>
console.log("!called");
let results = req.body.results;
console.info(results);
await sql.connect(config, function(err)
if (err) console.log(err);
// create Request object
var request = new sql.Request();
request.input("Results", sql.VarChar, results);
// query to the database and get the records
request.execute("dbo.StoreAnswers", function(err, recordset)
if (err) console.log(err);
// send records as a response
res.json(recordset);
);
);
res.statusCode = 400;
res.statusMessage = "bad request";
// res.json( message: "Email Missing" );
);
这是控制台信息（结果）
[
[0]
[0] answer: 'yes',
[0] question: 'Is the keyboard separate from the screen?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Does the keyboard tilt?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Is it possible to find a comfortable typing postion?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Do you have a good keyboard technique?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Are the characters on the keyboard clear and readable?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: "Is your mouse or other pointing device suitable to the task you're using it for?",
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Is the mouse (or other pointing device) located sufficently close to you? ',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Is there support for your wrist and forearm when using the mouse(or other pointing device)',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Does the mouse (or other pointing device) work smoothly at a speed that suits you?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Can you easily adjust the software settings for speed and accuracy of the pointer?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Are the characters on your screen clear and readable?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Is the text size on your screen confortable to read?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Is the image on your screen free from flicker and jitter?',
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: "Is your screen's specification suitable for its intended use?",
[0] state: 'Accepted'
[0] ,
[0]
[0] answer: 'yes',
[0] question: 'Is the brightness and/or contrast on your screen adjustable?',
[0] state: 'Accepted'
[0]
[0] ]
错误
RequestError: Invalid length parameter passed to the LEFT or SUBSTRING function.
【问题讨论】：
SQL Server 的版本？ 我相当确定的最新版本 【参考方案1】：此解决方案将源代码行转换为 json 字符串（您的日志行已经与 json 非常相似，因此只需要稍作更改）。通过这种方式，您可以使用标准 SQL Server 函数来读取它们的值，从而使代码更简洁、更易于维护，并且有望比我的其他建议更健壮。
仍然使用带有换行符的 string_split 函数分隔行。
create procedure StoreAnswers(@text varchar(max))
as begin
insert into QuestionResponses(question, answer, state)
select json_value(json, '$.question') as question,
json_value(json, '$.answer') as answer,
json_value(json, '$.state') as state
from (select replace(replace(replace(substring(value, charindex('', value), len(value)), 'answer: ', '"answer": '), 'question: ', '"question": '), 'state: ', '"state": ') as json
from string_split(@source, char(10))
where value like '%%%') as jsons
end;
json_value 是从 json 字符串中提取值的 SQL 函数。
从源代码行到 json 的转换示例。来自：
0: 答案：“是”，问题：“键盘是否与键盘分开？ screen?", state: "Declined with Solution defined"
...我们将其转换为：
"answer": "yes", "question": "键盘是否与 screen?", "state": "Declined with Solution defined"
我们只是删除了初始行号，并在标识符中添加了引号。这个表达式做了那些改变：
replace(replace(replace(substring(value, charindex('', value), len(value)), 'answer: ', '"answer": '), 'question: ', '"question": '), 'state: ', '"state": ')
您可以在此处实时查看从源文本中提取每个值的过程：http://sqlfiddle.com/#!18/9eecb/74419
【讨论】：
【参考方案2】：我不能说太多关于如何用 express 编写，但你需要的是一个类似的 SQL 查询
INSERT INTO `table_name`
(answer, question, created_at, updated_at)
VALUES
$sql_insert_values
sql_insert_values 将是具有逗号分隔值的字符串数组。 每个字符串将代表一个字段，并且每一列都有逗号分隔的值。
如果您在某个字段上有一些唯一键或索引，请添加 ON DUPLICATE KEY UPDATE value = VALUES(value)。
如果您有任何疑问，请随时询问。
PS： 发送到 SQL 的值将采用以下格式：
["(question value in string, answer value in string, date-time, date-time)", "()", "()"]。这是一个更简单的查询示例：
INSERT INTO tbl_name (a,b,c)
VALUES(1,2,3), (4,5,6), (7,8,9);
更多信息请参考：https://dev.mysql.com/doc/refman/8.0/en/insert.html
【讨论】：
很好，那么这将如何在存储过程中完成。对象变量数据类型是什么？ 您需要稍微重新格式化您的数据。$sql_insert_values 将是一个数组。这是一个例子 ["('这是我的问题', '这是我的答案', Time.now, Time.now") , "('这是我的第二个问题', '这是我的第二个答案', Time.now, Time.now)" ]
嘿，我已经更新了存储过程工作的问题？
抱歉 henry 我对存储过程了解不多。我只能帮你查询。
@henrypf 如果您从查询中获得帮助，您可以投票赞成我的回答。【参考方案3】：
您可以使用带有换行符的 string_split 将您的文本分成几行，然后使用 substring 在这些行中分隔您的值，使用 charindex 来标识它们的位置。
declare @text varchar(max) =
'0: answer: "yes↵", question: "Is the keyboard separate from the screen?", state: "Declined with soloution defined"
1: answer: "yes", question: "Does the keyboard tilt?", state: "Accepted"
2: answer: "Question declined But not a problem", question: "Is it possible to find a comfortable typing postion?", state: "Accepted"
3: answer: "yes", question: "Do you have a good keyboard technique?", state: "Accepted"
4: answer: "Question declined But not a problem", question: "Are the characters on the keyboard clear and readable?", state: "Accepted"
5: answer: "sgdfgdfgdf", question: "Is your mouse or other pointing device suitable to the task you''re using it for?", state: "problem specified"
6: answer: "yes", question: "Is the mouse (or other pointing device) located sufficently close to you? ", state: "Accepted"
7: answer: "sdfsdfsdfsd", question: "Is there support for your wrist and forearm when using the mouse(or other pointing device)", state: "Declined with soloution defined"
8: answer: "yes", question: "Does the mouse (or other pointing device) work smoothly at a speed that suits you?", state: "Accepted"
9: answer: "asdasdas", question: "Can you easily adjust the software settings for speed and accuracy of the pointer?", state: "Declined with soloution defined"
10: answer: "asdasdads", question: "Are the characters on your screen clear and readable?", state: "problem specified"
11: answer: "yes", question: "Is the text size on your screen confortable to read?", state: "Accepted"
12: answer: "asdasdasd", question: "Is the image on your screen free from flicker and jitter?", state: "Declined with soloution defined"
13: answer: "asdasdasd", question: "Is your screen''s specification suitable for its intended use?", state: "problem specified"
14: answer: "yes", question: "Is the brightness and/or contrast on your screen adjustable?", state: "Accepted"'
select substring(value, charindex('answer: "', value) + 10, charindex('", ', value, charindex('answer: "', value) + 10) - charindex('answer: "', value) - 10) as answer,
substring(value, charindex('question: "', value) + 11, charindex('", ', value, charindex('question: "', value) + 11) - charindex('question: "', value) - 11) as question,
substring(value, charindex('state: "', value) + 8, charindex('"', value, charindex('state: "', value) + 8) - charindex('state: "', value) - 8) as state
from string_split(@text, char(10))
您可以在这里看到提取工作：http://sqlfiddle.com/#!18/9eecb/74353
因此，接受您的文本并将其插入表中的存储过程将是：
create procedure StoreAnswers(@text varchar(max))
as begin
insert into QuestionResponses(answer, question, state)
select substring(value, charindex('answer: "', value) + 10, charindex('", ', value, charindex('answer: "', value) + 10) - charindex('answer: "', value) - 10) as answer,
substring(value, charindex('question: "', value) + 11, charindex('", ', value, charindex('question: "', value) + 11) - charindex('question: "', value) - 11) as question,
substring(value, charindex('state: "', value) + 8, charindex('"', value, charindex('state: "', value) + 8) - charindex('state: "', value) - 8) as state
from string_split(@text, char(10))
end;
【讨论】：
问题、答案和状态有时会发生巨大变化，这会影响这个吗？ 啊，好吧，我想如果修改这可能就是答案。目前它正在抛出错误消息`RequestError: Invalid length parameter passing to the LEFT or SUBSTRING function.` 完全更新问题，如果您知道为什么会发生这种情况，请告诉我【参考方案4】：我认为您必须创建一个额外的表 t_servey(id, name, ...) 并在 t_question 表中使用 servey_id 以备将来使用。
t_question(
id,
servey_id, -- link on t_servey table
answer,
question,
created_at,
updated_at
)
并添加bining变量（？）以插入到表中：
insert into t_question (servey_id, answer, question, created_at, updated_at) values (?, ?, ?, ?, ?)
【讨论】：
【参考方案5】：为什么你不在你的 express 应用中使用 orm
喜欢续集 它将使您的生活更轻松，并消除在您的应用程序中构建 sql 语句的所有麻烦
检查它的文档 https://sequelize.org/
在你的情况下使用 sequlize
1- 在数据库中创建你的表
2- 在您的快速应用程序中为该表制作模型
3-调用model.bulkCreate(整个对象)
试试看
【讨论】：
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