How to add a new column to an existing table with websql

Question

I have an android app (created with cordova) that is already live and in use. There are some data being stored on the device database. I have to make an update that requires an additional column to one of the tables in the database. I want to add the new column without the need to clear the app storage so i created a function that attempts to add a new column before executing some other function dependant on that table. here is the code for that altering code

var alterEntryTable = function()
{
    qObj = $q.defer();

    dbService.db.transaction(function(tx) {

        tx.executeSql(
            'ALTER TABLE entry ADD created_at TIMESTAMP ',
            [],
            function (tx, rss) {
                qObj.resolve({error: false});
            }, function (tx, rss) {
                qObj.resolve({ error: true});
            }
        );
    });

    return qObj.promise;
};

the problem is that it always returns an error. someone help please. Thank you

Answer 1

The second parameter in your error handler is a SQLError object. You can log its message property to get details on the error.

function (tx, rss) {
    console.log(rss.message);
    qObj.resolve({ error: true});
}

Did the error message help at all? I think you're missing COLUMN in your SQL. It should be ALTER TABLE entry ADD COLUMN created_at TIMESTAMP .

Also timestamp is not a datatype in SQLite , but it's harmless to keep it there.