given code how to handle async call inside if the condition.not store newname in name and run callback first
var xyz = function (data, callback) {
try{
pool.query('select * from devices',[1],function(err,result){
if(result.rows[0].name = 12){
pool.query('select * from devices',[12],function(err,result){
result.rows[0].name = result.rows[0].newname;
}
}
callback(result.rows[0].name);
});
}catch(err){
callback(err);
}
}
Since you tagged async-await, you'll need to use Promise's
So
Create a helper function like this
const promiseQuery = (pool, ...args) => new Promise((resolve, reject) => {
pool.query(...args, (err, result) => {
if (err) return reject(err);
resolve(result);
});
});
Then use it like this
var xyz = async function (data, callback) {
try {
const result = await promiseQuery(pool,'select * from devices', [1]);
if (result.rows[0].name = 12) {
const result = await promiseQuery(pool, 'select * from devices', [12]);
result.rows[0].name = result.rows[0].newname;
callback(result.rows[0].name);
}
} catch (err) {
callback(err);
}
}
Of course, some db's already have a promisified version of their functions
So it would be like
var xyz = async function (data, callback) {
try {
const result = await pool.query('select * from devices', [1]);
if (result.rows[0].name = 12) {
const result = await pool.query('select * from devices', [12]);
result.rows[0].name = result.rows[0].newname;
callback(result.rows[0].name);
}
} catch (err) {
callback(err);
}
}