ORDER BY and dates issue

Hello, I encounter an issue trying to ordering my data containing date columns.

Here an example of code (Apps script):

function myTest() {
  var data =[{id: 200, fromDate: new Date("2022-11-29"), toDate: new Date("2022-11-29")}, 
    {id:  100, fromDate: new Date("2022-11-30"), toDate: new Date("2022-11-30")},
    {id:  101, fromDate: new Date("2022-11-30"), toDate: new Date("2022-11-30")}, 
    {id:  102, fromDate: new Date("2022-11-30"), toDate: new Date("2022-11-30")}, 
    ];

  var db = new alasql.Database("MyDB");
  db.exec('CREATE TABLE mytable (id INT, fromDate Date, toDate Date)');
  db.tables.mytable.data = data;

  console.log(db.tables.mytable.data);
  var res = db.exec(`SELECT id FROM mytable ORDER BY fromDate, id ASC`,);

  console.log(res);
}

The result I get:

[ {id: 200}, {id: 102}, {id: 101}, {id: 100} ]

But the result I expect is:

[ {id: 200}, {id: 100}, {id: 101}, {id: 102} ]

Any idea of what’s happening ?

[Buroni]

I’ve spent some time looking into this issue. It seems like there’s several factors involved.

Short answer: You can get round this by setting alasql.options.valueof = true;. For example see this fiddle http://jsfiddle.net/3rbL75hc/

Long answer:

This seems to be partially fixed on the develop branch for 2.1.3. If I recreate @fabads’ example in a local test on develop, it reproduces the error. However if I add fromDate to the select query columns then it works as we’d expect.

# This doesn't work on `develop`
SELECT id FROM mytable ORDER BY fromDate, id ASC

# This does work
SELECT id, fromDate FROM mytable ORDER BY fromDate, id ASC

# Note that neither work on <2.1.3

The issue here is that the date needs to be converted to a Unix epoch via date.valueOf(). This only happens when the column type explicitly is DATE, DATETIME, STRING or NUMBER: see 426orderby.js#L60. However, the fromDate column as well as all associated type information is dropped out of the query object when it’s not explicitly SELECTed.

This is also what causes the issue in @mathiasrw’s example: since it’s an anonymous query, there’s no type information for date so the .valueOf() prefix is never added to the date.

I’m looking into how to get round this, but someone more familiar with the codebase may be able to make a quicker fix with this information!

[mathiasrw]

Any luck @Buroni ?