Is it possible to have a variable either inside quotation marks or NULL when checking for case within a string in JavaScript

Question

Is it possible to have a variable either inside quotation marks or NULL when checking for case within a string in JavaScript

The challenge lies in titling this particular question, but demonstrating it is quite straightforward. My goal is to include multiple value sets in an SQL insert statement like the following:

var sqlInsertString = `INSERT INTO events (url) VALUES`
var sqlInsertValuesString = `('${event.url ? event.url : null}', null, 1, 2, 3)`

pg_client.query(sqlInsertString + sqlInsertValuesString)

This process occurs within a loop, hence the need for separating the insert string and values string. What I aim for is to have the URL inserted as 'https://www.example.com' with quotes if event.url contains a URL, and to insert null if event.url is empty.

In my current code snippet above, 'null' is inserted as a string with quotes instead of an actual null value in the database. Removing the quotes would lead to errors due to the presence of ':' in the URL.

How can I modify the sqlInsertValuesString to either provide a valid URL string or a genuine null without quotation marks using this approach?

javascript sql

Answer 1

Answer №1

Using parametrised queries serves multiple purposes, not just for preventing injection attacks. It streamlines the process like this:

pg_client.query(
  "INSERT INTO events (url, nothing, one, two, three) VALUES ($1, $2, $3, $4, $5)",
  [event.url || null, null, 1, 2, 3]
)
.then(res => ...)
.catch(err => ...)

No need to worry about quoting, all the technicalities are taken care of by the driver.

Even if security isn't your primary concern, utilizing parametrised queries is beneficial for clarity and as a best practice: by consistently implementing parametrised queries always, you eliminate the risk of overlooking possible injections and inadvertently creating vulnerabilities in your program.

Answer 2

Using parametrised queries serves multiple purposes, not just for preventing injection attacks. It streamlines the process like this:

pg_client.query(
  "INSERT INTO events (url, nothing, one, two, three) VALUES ($1, $2, $3, $4, $5)",
  [event.url || null, null, 1, 2, 3]
)
.then(res => ...)
.catch(err => ...)

No need to worry about quoting, all the technicalities are taken care of by the driver.

Even if security isn't your primary concern, utilizing parametrised queries is beneficial for clarity and as a best practice: by consistently implementing parametrised queries always, you eliminate the risk of overlooking possible injections and inadvertently creating vulnerabilities in your program.

Answer 3

Answer №2

If you prefer not to use backticks, you have the option to do it differently

var event = {};
event.url = 'http://someurl.com';
var sqlInsertString = "INSERT INTO events (url, a, b, c, d) VALUES ";
var sqlInsertValuesString = "('" + (event.url ? event.url + "'" : null) + ", null, 1, 2, 3)";

console.log(sqlInsertString + sqlInsertValuesString);

var event = {};
var sqlInsertString = "INSERT INTO events (url, a, b, c, d) VALUES ";
var sqlInsertValuesString = "(" + (event.url ? "'" + event.url + "'" : null) + ", null, 1, 2, 3)";

console.log(sqlInsertString + sqlInsertValuesString);

Answer 4

If you prefer not to use backticks, you have the option to do it differently

var event = {};
event.url = 'http://someurl.com';
var sqlInsertString = "INSERT INTO events (url, a, b, c, d) VALUES ";
var sqlInsertValuesString = "('" + (event.url ? event.url + "'" : null) + ", null, 1, 2, 3)";

console.log(sqlInsertString + sqlInsertValuesString);

var event = {};
var sqlInsertString = "INSERT INTO events (url, a, b, c, d) VALUES ";
var sqlInsertValuesString = "(" + (event.url ? "'" + event.url + "'" : null) + ", null, 1, 2, 3)";

console.log(sqlInsertString + sqlInsertValuesString);

Answer 5

Answer №3

To enhance clarity, it would be beneficial to break down the assignment into two steps:

let eventUrl = event.url ?? null;
const sqlInsertString = `INSERT INTO events (url) VALUES (${eventUrl}, null, 1, 2, 3)`

The nullish coalescing operator was utilized for assigning a value to eventUrl.

Answer 6

To enhance clarity, it would be beneficial to break down the assignment into two steps:

let eventUrl = event.url ?? null;
const sqlInsertString = `INSERT INTO events (url) VALUES (${eventUrl}, null, 1, 2, 3)`

The nullish coalescing operator was utilized for assigning a value to eventUrl.

Answer 7

Answer №4

If you give it a shot

`(${event.url ? `'${event.url}'` : `null`})`

There will be single quotes enclosing the URL if it's present, but not for null values.

Answer 8

If you give it a shot

`(${event.url ? `'${event.url}'` : `null`})`

There will be single quotes enclosing the URL if it's present, but not for null values.

Answer 9

Answer №5

In my search on Google, I also discovered that using backslashes to escape the backtick can be effective:

${event.url ? (`\`` + event.url + `\``) : null},

However, after careful consideration, I found the selected response to be superior.

Answer 10

In my search on Google, I also discovered that using backslashes to escape the backtick can be effective:

${event.url ? (`\`` + event.url + `\``) : null},

However, after careful consideration, I found the selected response to be superior.

Is it possible to have a variable either inside quotation marks or NULL when checking for case within a string in JavaScript

Answer №1

Answer №2

Answer №3

Answer №4

Answer №5

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