sql column default value with functions in javascript

I am new to SQL, but I am trying to set up a database in the html5 sql storage using a javascript in a jquery $(document).ready statement. I have been testing in Chrome, and firefox, but firefox does not work at all, and the problem that I have in chrome, is that I can set up a d开发者_开发知识库efault value just fine if it is a static value, but when I try to use a function, things do not turn out so well, I think that this code only calls the default function once when I actually want it to call the function every time. However, when I try to do that the function ErrorDB gets called. here is the code:

$(document).ready(function()
{
var db;
try{if(window.openDatabase){
    db =openDatabase("fetchnotes", "1.0","fetchnotesDB",1000000);
    if (!db) {alert("failed to load database on disk"); return;};   
    }     
            else{
       alert("could not open database.");
       return;
    }

}catch(err){alert("error "+err); return;}
db.transaction(initializeDB, errorDB);
});
function initializeDB(tx){
    tx.executeSql('Drop TABLE IF EXISTS NOTES');
    tx.executeSql('CREATE TABLE IF NOT EXISTS'+
    ' NOTES(ID int primary key,NoteText, LastModified Date NOT NULL DEFAULT "'  
            +defaultLastModified()+ '")');
    tx.executeSql('INSERT INTO NOTES (ID, NoteText) VALUES (1, "make a better database") ');
}

function errorDB(tx,err)
{
    alert("error "+err);        
}
function defaultLastModified()
{
    var result= new Date();
    return result;      
}

Okay I found something of a solution for the problem, which is that That I had an incorrect data type as well as a few other things. the for corrected code is here:

tx.executeSql("CREATE TABLE IF NOT EXISTS"+
    " NOTES(ID INTEGER PRIMARY KEY,NoteText TEXT ," +
    "LastModified TIMESTAMP DEFAULT (datetime('now','localtime')));");

you technically do not need the 'localtime', leaving it out means that the time would be in GMT which is standard for SQL. However, I still do not know how to in general get a user defined function to be the default value, which is still my main question.

There are 3 things I think are wrong.

1. I'm pretty sure a JS Date-object won't fit in a SQL-query (... "' + defaultLastModified() + "' ...).
2. If it would fit, it wouldn't work as you think either: defaultLastModified() will return now, so when you add a record in 2 weeks, it'll still contain now (so 2 weeks prior to adding the record).
3. Haven't dates (in SQL) got a default value by default (that'll automatically fill in the real now, always)?

My understanding is that executeSql is only supported on WebKit based browsers, thus it will not work in Firefox or IE. I would suggest looking for another method to write to a browser side database.

For WebKit browsers (Chrome, Safari) you may want to try using a semicolon to close the SQL statement.

Example

tx.executeSql('CREATE TABLE IF NOT EXISTS NOTES(ID int primary key,NoteText, LastModified Date NOT NULL DEFAULT "' + defaultLastModified() + '");');