sort Find how many distinct values are among the certain column

Question

I want to send the alert message to client.

So, I found that.

res.send(<'alert("XXX!!!")');

In this way, I didn't use res.render();

I want to use together.

Or

I want to send alert message using res.render();

How do I this?

This is the code.

			if (err)
				console.log(err);
			
			if (flag === 1) { //함수 이름 중복
				try {
					//res.send('<script>alert("함수 이름 중복!")</script>');
					LoadDB(res);
				} catch (exception) {}
			}
			else {
				//(4) 데이터베이스 insert 쿼리
				var query = "insert into automation_script set ?";
				conn.query(query, set, function (error, result, fields) {
					if (error) {
						console.log('Insert_DB error' + error);
					} else {
						try {
							LoadDB(res);
						} catch (exception) {}
					}
				});
			}
			//(5) 데이터베이스 해제
			conn.end();

Thanks you.

Solution 1

I would start with cut since you only care about uniqueness in column 2:

cut -d' ' list.txt

results in:

1
2
1
3
6
7
6

Now you want unique values; uniq will do that, but only if it's sorted. If you're going to sort, go ahead and use sort's -u flag:

cut -d' ' -f2 list.txt | sort -u

Results in:

1
2
3
6
7

and now you can use wc to count the number of lines of output:

cut -d' ' -f2 list.txt | sort -u  | wc -l

which gives you:

5

Note that we're relying a specific format for the list.txt file -- no spaces in people's names!

Solution 2

I would go with:

sort -k2,2 -u names | wc -l
5

Where names has this content:

cat names
Joe 3
Jack 1
Ulysses 6
Fox 2
Cassidy 1
Jones 6
Kevin 7

Comments

[Vinod Louis]

how about sending your alert as text and at client side use eval() to execute prior to that why such need ?

[Soubhik Mondal]

@VinodLouis isn't eval a bad idea?

[Vinod Louis]

@BlazeSahlzen ofcourse it is if adulterated thats why I asked why such need

[Fortuneman]

@VinodLouis eval? Oh! I have to research the eval. Thanks you!

[Prathamesh More]

This will help you stackoverflow.com/questions/56542357/…

[Fortuneman]

First, Thanks you Jamie. I will remember your advice. In fact, I'm novice programmer especially javascript and node.js. But, I got the project that I had to make using javascript and node.js. It's hard but interesting. I will research the http and web socket. Thanks again.

[Jeff Schaller]

Clever combination of the key field with -unique!

[BennX]

While this code may answer the question, providing additional context regarding why and/or how this code answers the question improves its long-term value.