Update only one column in user info - MySQL NodeJS - mysql

Question

I'm builing a classic CRUD (create, read, update, delete) API with NodeJS/Express and MySQL.
I created a route to update my user informations that works fine.
The problem :
If I dont send EVERY data (first_name, last_name etc...), the columns with no data update to undefined in MySQL database, and the column with data don't update. I would like that if I don't send data, no change happens for the columns, and only the one with datas change.
Here is my controller :
module.exports.updateUser = (req, res, next) => {
if (req.method == "PUT") {
let userDetails = `UPDATE users SET first_name = '${req.body.first_name}', last_name = '${req.body.last_name}', user_name = '${req.body.user_name}' WHERE id = ${req.params.id}`;
sql.query(userDetails, function (err, result) {
if (!err) {
res.status(200).json({ message: "User infos updated." })
} else {
res.status(401).json({ message: "Error when updating user infos." })
}
})
}
}
So, if I make a PUT request on an existing user in db with only the mail for example :
{
"mail": "test2#test2.com"
}
all my user datas become null and user.mail stays the same.
Anyone could help me on this ?
Thank you 🙂

Answer 1

Use this query for update one or more filled update at a time
module.exports.updateUser = (req, res, next) => {
if (req.method == "PUT") {
let query = '';
if(req.body.first_name){
query = `first_name =
'${req.body.first_name}'`
}else
if(req.body.last_name){
query = ` last_name =
'${req.body.last_name}'`
}else
if(req.body.user_name){
query = `user_name =
'${req.body.user_name}'`
}eles if(req.body.first_name
&& req.body.last_name)
{
query =`first_name = '${req.body.first_name}', last_name = '${req.body.last_name}'`
}else if(
req.body.last_name && req.body.user_name
{
query = `last_name = '${req.body.last_name}', user_name = '${req.body.user_name}'`
}else if(req.body.first_name
&& req.body.last_name && req.body.user_name)
{
query =`first_name = '${req.body.first_name}', last_name = '${req.body.last_name, user_name = '${req.body.user_name}'}'`
}
let userDetails = `UPDATE users SET ${query} WHERE id = ${req.params.id}`;
sql.query(userDetails, function (err, result) {
if (!err) {
res.status(200).json({ message: "User infos updated." })
} else {
res.status(401).json({ message: "Error when updating user infos." })
}
})
}
}

Answer 2

Thanks to #jutendra, it works.
After few months (and gained skills), here is a cleaner version if ever someone is interested :
module.exports.updateUser = (req, res, next) => {
if (req.method !== "PUT") return;
const updates = [];
if (req.body.first_name) updates.push(`first_name = '${req.body.first_name}'`);
if (req.body.last_name) updates.push(`last_name = '${req.body.last_name}'`);
if (req.body.user_name) updates.push(`user_name = '${req.body.user_name}'`);
if (updates.length === 0) {
res.status(400).json({ message: "No updates provided" });
return;
}
const query = `UPDATE users SET ${updates.join(", ")} WHERE id = ${req.params.id}`;
sql.query(query, (err, result) => {
if (!err) {
res.status(200).json({ message: "User infos updated." });
} else {
res.status(401).json({ message: "Error when updating user infos." });
}
});
};