How to select a dynamic list of fields generated on the fly?

[john dimm]

The SELECT query builder takes a variable number of arguments, 

  db.select(a1, a2, a3)...

But I don't know how many fields will be requested.  The schema is determined at runtime.

Is there a way to pass an array or comma-separated list of fields to db.select?

[Demetrios Papadopoulos]

IIUC your question, this can be done with simple JS features, and does not need any special feature from Lovefield.

Using ES6 spread operator "...":

let myDynamicFieldList = calculateList(); // Returns an array of Lovefield columns at runtime.
db.select(...myDynamicFieldList).from(myTable).exec();

Without ES6, using plain old Function.apply (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/apply)

let myDynamicFieldList = calculateList(); // Returns an array of Lovefield columns.
db.select.apply(db, myDynamicFieldList).from(myTable).exec();

Hope this helps,

Thanks