How to input declared variable in js into mssql query in node.js?

Question

I have introduced some variables a,b and c as follows in my code

var a = 10; var b = 90; var c = b - a + 1;

req2.query('SELECT TOP(81) [Numbers], [Square_Root] FROM Kiso_task_table WHERE Numbers   >=  10  AND Numbers <= 90', function (err, data) {
        if (err) {
            console.log(err);
            return;
        }
        else {
            console.log(data);
        }
        conn.close();
    });

I don't want to enter my data into query by "typing them from my finger". To be more precise, instead of req2.query('SELECT TOP(81) I want to have req2.query('SELECT TOP(c), where variable c is already defined with assigned value.

SELECT TOP(81)... will give you up to 81 rows. I'm honestly not 100% sure what you are trying to do. Are you trying to concatenate the variables (they don't seem to appear in your code anywhere)? Can you edit the post and add the expected results? — Jacob H
– Jacob H, Commented Nov 9, 2018 at 13:44

squillman · Accepted Answer · 2018-11-09 15:20:46Z

1

You need to make a parameterized query.

req2.query(`SELECT TOP(${c}) [Numbers], [Square_Root] FROM Kiso_task_table WHERE Numbers >=  ${a}  AND Numbers <= ${b}`, function (err, data) {
        if (err) {
            console.log(err);
            return;
        }
        else {
            console.log(data);
        }
        conn.close();
    });

edited Nov 9, 2018 at 15:20

answered Nov 9, 2018 at 13:53

squillman

13.7k3 gold badges45 silver badges65 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

zorro47 Over a year ago

Having introduced those changes, console displays " RequestError: Syntax error, permission violation, or other nonspecific error at StreamEvents.req.once.err"

squillman Over a year ago

Undeleted... I updated my answer with more code. I'm assuming you're using the mssql npm package to query SQL Server. Can you confirm that's the case?

zorro47 Over a year ago

Exactly, I'm using mssql npm package

squillman Over a year ago

Argh, sorry... I put single quotes in instead of backticks. I've updated the answer. Give it another try.

squillman Over a year ago

Ok. Not sure what the issue is, it works on my side.

|

zorro47 · Accepted Answer · 2018-11-09 17:27:47Z

0

req2.query('SELECT TOP('+ c +')[Numbers], [Square_Root] FROM Kiso_task_table WHERE Numbers >=' + a +  'AND Numbers <=' + b, function (err, data) {
        if (err) {
            console.log(err);
            return;
        }
        else {
            console.log(data);
        }
        conn.close();
    });

answered Nov 9, 2018 at 17:27

zorro47

2211 silver badge12 bronze badges

1 Comment

squillman Over a year ago

While this works, don't do this. You open yourself up to SQL injection attacks.

Collectives™ on Stack Overflow

How to input declared variable in js into mssql query in node.js?

2 Answers 2

6 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

6 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related