I am trying to print a specific column of a mysql table told by the user in runtime (without using if else ,which will make code tidious)
var columns = ['D'];
("SELECT ?? FROM money",[columns], function (err, results, fields)
IN THIS I HAVE TO SPECIFY COLUMN NAME(D) --
results[2].D
OR
var x = String("D") + i.toString();
results[2].x
THIS DIDT WORKED
If you want to access a column by name, but you have the name in a variable, remember JavaScript objects allow access that way:
let column = 'D';
results[2][column] // => D column value
Your var x
defines an x
variable. This, however:
results[2].x
This looks up a property named literally x
on that result.
It's also not clear what the intent behind String("D")
is, as "D"
is already a string. Making a superstring?
JavaScript has an interpolation system specifically for this:
var x = `D${i}`;
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