Twitter: raymondcamden


Address: Lafayette, LA, USA

Example of PhoneGap's Database Support

10-20-2011 65,816 views Mobile, jQuery, JavaScript, HTML5 96 Comments

Folks who have used Adobe AIR before already know (or hopefully know) about it's cool, built-in database support. Any AIR application (whether written in Flex or HTML - you do remember you can do AIR with HTML, right?) can make use of an embedded SQLite database. This is incredibly useful for applications and pretty darn easy to use as well. PhoneGap also has built in support for SQLite via their storage support. In this blog entry I'll walk you through a sample application I've created that makes use of the feature. I'll also point out some of the mistakes I made while writing so that hopefully you can avoid the issues I ran into.

First - it is important to carefully read PhoneGap's storage documentation. I don't know why - but the biggest issue I've had with PhoneGap so far has been around my incorrect assumptions not matching up with reality. I guess I shouldn't be surprised there, but with PhoneGap I've found it really critical to carefully read the docs. It isn't that PhoneGap is brittle per se, but you really need to ensure you know what you're doing. Consider yourself warned.

Along with PhoneGap's docs, you want to read the W3C spec for Web SQL Database support. It definitely helped fill in some things that the PhoneGap docs didn't cover. As an example, the PhoneGap docs enumerate the error codes for the SQLError object, but don't tell you the actual values that go with them. The W3C docs for SQLError though have both the labels and the codes.

For folks who are familiar with SQLite in AIR, there are two main differences I've found between the AIR and PhoneGap platforms.

First - it seems (although I've not confirmed this) that PhoneGap only supports asynchronous connections. That's not a bad thing typically, but I tend to prefer synchronous connections since they are a lot simpler to work with. They can lock your application up if you need to perform a particularly long operation, but I like having the option at least. I'll typically use two connections in an AIR app. I'll have a synchronous one for setup and then an asynchronous one to handle post-launch operations. Again - with PhoneGap you only have the asynchronous option.

Second - while both AIR and PhoneGap support transactions through SQLite, PhoneGap requires all SQL transactions to go through a transaction. This adds a level of complexity to your code that may be a bit confusing at first, but once you've worked through a couple of examples it really isn't that big of a deal. It tended to bite me in the rear because I made the mistake of running "executeSQL" on my transaction object instead of "executeSql". The application reported it as a database error because the transaction callback was executing. This was confusing and hard to debug.

Ok - so let's talk about the application. My demo application is called SimpleNotes. It's a very poor, very limited note taking application. It's got a grand total of two screens. The first is a list of your current notes.

You can click a note to edit it, or simply click Add Note.

So how does it work? I've got an event handler that listens in for the deviceready event. This event is fired by PhoneGap when the hardware is ready for business time. I began by having it call a function named phoneReady:

view plain print about
1function phoneReady() {
2 //First, open our db
3 dbShell = window.openDatabase("SimpleNotes", 2, "SimpleNotes", 1000000);
4 //run transaction to create initial tables
5 dbShell.transaction(setupTable,dbErrorHandler,getEntries);
6}

In case your curious why I named the database twice - the first string is the database name while the second one is the display name. Much like my name is Raymond but I write it as G-Megabyte. (Now you know...) The second argument is the version. This can be used to shift the application from one database version to another. Normally you would update a database with SQL though so I'm not sure that folks would change this often in production. The last argument is the size. I picked 1000000 because I thought it looked nice on paper. Notice then we have a transaction to run setupTable. This is where I'll do my initial definitions.

view plain print about
1//I just create our initial table - all one of em
2function setupTable(tx){
3 tx.executeSql("CREATE TABLE IF NOT EXISTS notes(id INTEGER PRIMARY KEY,title,body,updated)");
4}

As you can see, I use "IF NOT EXISTS" in my creation script. That makes it safe to run more than once. For information on valid SQL syntax for SQLite, check their docs. Ok, now if you remember the original transaction call, it had 2 more arguments. The second was a generic error handler, and the third was getEntries. First let's look at the error handler:

view plain print about
1function dbErrorHandler(err){
2 alert("DB Error: "+err.message + "\nCode="+err.code);
3}

Most likely, and especially for an application like this, any error should be logged, possibly emailed, and also result in the termination of the app itself. My application is pretty useless if it can't do what it needs to with the database. But how you handle your errors will be up to the individual application. Let's more on then to getEntries.

view plain print about
1//I handle getting entries from the db
2function getEntries() {
3 dbShell.transaction(function(tx) {
4 tx.executeSql("select id, title, body, updated from notes order by updated desc",[],renderEntries,dbErrorHandler);
5 }, dbErrorHandler);
6}

So compared to the earlier transaction call I got a bit fancier here. I've embedded the function within the transaction call itself. It may be a bit hard to read there so let me rewrite this in pseudo-code so it is clear:

view plain print about
1Start a transaction:
2 execute my sql, and on a good result, run renderEntries, and on a bad result, run dbErrorHandler
3If the transaction fails: run dbErrorHandler

I sometimes tried to put the result handler in the transaction call, but if you do that, you don't get passed the result of the SQL execution. So... don't do that. The second argument to executeSql (the empty array) is how bound parameters are handled. Since I have none I just pass it as an empty array. Now let's look at renderEntries.

view plain print about
1function renderEntries(tx,results){
2 doLog("render entries");
3 if (results.rows.length == 0) {
4 $("#mainContent").html("<p>You currently do not have any notes.</p>");
5 } else {
6 var s = "";
7 for(var i=0; i<results.rows.length; i++) {
8 s += "<li><a href='edit.html?id="+results.rows.item(i).id + "'>" + results.rows.item(i).title + "</a></li>";
9 }
10 $("#noteTitleList").html(s);
11 $("#noteTitleList").listview("refresh");
12 }
13}

So a good portion of this is generic DOM manipulation and jQuery Mobile related, but focus on how I use the results attribute. I can easily check the length and handle an empty database. I can also easily loop over them and access the data. Pretty simple, right? Let's look at one more function. When saving a note, I'm either saving an existing note or editing a new one. I've got code in there to handle that, but let's focus on the actual save operation.

view plain print about
1function saveNote(note, cb) {
2 //Sometimes you may want to jot down something quickly....
3 if(note.title == "") note.title = "[No Title]";
4 dbShell.transaction(function(tx) {
5 if(note.id == "") tx.executeSql("insert into notes(title,body,updated) values(?,?,?)",[note.title,note.body, new Date()]);
6 else tx.executeSql("update notes set title=?, body=?, updated=? where id=?",[note.title,note.body, new Date(), note.id]);
7 }, dbErrorHandler,cb);
8}

So before we start - I'll say that the note argument is a simple JavaScript object. It's got values for title, body, and possibly the ID. The cb argument is simply a call back to execute. Notice how I handle insert versus update logic. Also note how i handle the bound parameters. Very much like AIR. It looks like you can't do named parameters like you can in Adobe AIR, so make your get your positions right.

And that's pretty much it. There's a lot more logic around to handle my form editing and the like, but you can see that yourself in the attached zip. The zip contains an unsigned APK as well as a copy of the code. Note - when saving a note I've got a weird page display issue going on. Anyone who fixes that gets mega bonus points from the pool.

Edit: For folks downloading the code, please see Anne's comment here.

Download attached file

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96 Comments

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  • Commented on 10-20-2011 at 9:53 AM
    Curious... In terms of security is it better to store sensitive data in this manner or to use the HTML 5 web storage? I am concerned about someone being able to look at the data outside the application.

    Thanks,

    --Dave
  • Commented on 10-20-2011 at 10:16 AM
    Hmm. This is a guess:

    SQLite uses a 'real' file. Therefore, someone should be able to find the file and get to it. In AIR you can encrypt the DB. I do not see that option here.

    For LocalStorage, it is tied to the browser instance and the domain. LocalStorage should still work fine w/n PhoneGap, and I'd assume be tied to the Application name (since there is no domain). My gut says it should be more secure - but I wouldn't put any money on it.
  • Commented on 10-20-2011 at 12:01 PM
    Great timing Raymond, as usual.
  • Commented on 10-20-2011 at 1:09 PM
    In my experience SQLite in Adobe AIR (Apollo) was one of highlights in Adobe System aspirations to access the desktop, I remember buying a book on Amazon to start learning (Beginning Adobe AIR). Now with PhoneGap I hope to have the time to use these products!!!
  • Jihane #
    Commented on 03-01-2012 at 5:36 AM
    Hello Sir, thank you so much for this tut, it did hel me a lot, but i am wondering where the database is? i can't find it, even after opening the DDMS perspective, on Eclipse, and i navigate to the app folder, but i am enable to find it,

    Please help, i need to find that database
  • Commented on 03-01-2012 at 5:49 AM
    See this: http://gauravstomar.blogspot.com/2011/08/prepopula...
  • Jihane #
    Commented on 03-01-2012 at 6:00 AM
    Thank's a lot for the reply, except, that in my case, and after that i did implemented the example from your blog, i'am not able to generate the DataBase, even if the interface shwos that notes are added, but i just can't find the generated dataBase.

    thank you
  • Commented on 03-01-2012 at 6:34 AM
    Well, for now, I'd say let's ignore your inability to find the database. Let's focus on your inability to use dbs at all.

    So your saying that when you work with a db, it shows notes being saved, but when you restart the app you see no notes?
  • Jihane #
    Commented on 03-01-2012 at 8:21 AM
    hi again,
    i am able to add notes on the graphic interface, and when in restart the app i do find the saved notes, but the problem is that i can't find the database(i want to see, and consult the saved data)

    Thank you .
  • Commented on 03-01-2012 at 8:51 AM
    Oh, ok, so then I'm out of luck. That blog entry I posted is the only one I know discussing the physical location of the db.
  • Jihane #
    Commented on 03-01-2012 at 8:54 AM
    all right then, but thanks so much an i keep looking for a solution,
    Thank you :)
  • Commented on 04-09-2012 at 4:31 AM
    I encountered a problem saving the notes, can i copy your version of phonegap.jar im using cordova1.5.jar. here's the error:
    Web Console(544): Uncaught TypeError: Cannot call method 'transaction' of undefined at file:///android_asset/www/js/main.js:56
  • Commented on 04-09-2012 at 7:28 AM
    Are you using the exact same version, except you used cordova1.5.jar instead of phonegap.jar?
  • amarjit #
    Commented on 05-18-2012 at 12:51 AM
    I want to use database file as such in the code because data is huge and adding that data to database is hard. I implemented same in Flex application but here i get "no such table" error. My code is:

    db = openDatabase("testdata.db","1.0","Apps Sample Database",5*1024*1024);
    db.transaction(function(tx){
             tx.executeSql("select * from test",[],function(t,res){
             var len=res.rows.length;            
             for(var i=0;i<len;i++){
                                  
                      $('#select-choice-b').append('<option val='+res.rows.item(i)['a']+"'>"+res.rows.item(i)['b']+"</option>");      
                      }
                               
          }, function(tx,error)
          {
             alert("database error:" +error.message);
          });

    here testdata.db is altready ctreated and have table test with data in it.
  • Commented on 05-18-2012 at 7:06 AM
    I believe you want to follow this: http://gauravstomar.blogspot.com/2011/08/prepopula...
  • Ganesh #
    Commented on 05-23-2012 at 5:46 AM
    could you explain me with sample code for connect the MySQl database in phonegap for android project

    Thanks in Advance
  • Commented on 05-23-2012 at 6:10 AM
    You can't run MySQL on a device. It would need to be on a remote server. You can then use JavaScript/Ajax to hit it via something on the server, like ColdFusion, to handle the connection.
  • Ganesh #
    Commented on 05-24-2012 at 3:43 AM
    Than you for your response!Actually i trying for an android app using phone gap which one used for the tracking the bus routes.so for that purpose i have to connect the database or any existing server.i tried with java script and php .but i did n't get success .could you please suggest with some useful code to me.its very use full me.

    A great thanks in advance
  • Commented on 05-24-2012 at 9:52 AM
    Well, it depends on what went wrong. :)

    FIrst off - are you sure your PHP code is right? I'd test that without PhoneGap. You need a PHP script that can respond to remote requests and return database information in JSON format. You can do this w/o touching PhoneGap at all and it will make testing easier.

    At that point, you switch back to your PhoneGap app and see if the Ajax calls work now.
  • venkata #
    Commented on 05-28-2012 at 7:00 AM
    HI.i really lot of things learn t from this blog.thank you providing this extraordinary blog for us. i am new to phone gap.and i want use web services in android app.can any one give detail information about it and any .js or jar files to copy into project?and if you give sample code to me a grateful thanks to you.
  • Commented on 05-28-2012 at 8:00 AM
    Are you talking about the formal definition of Web Services, ie those that use SOAP? If so, you will need to find a JavaScript library that works well with it. SOAP is just XML, but it is very verbose and very stringent on how you use it. If at all possible, I'd recommend a service that uses JSON instead.
  • Abraham #
    Commented on 10-02-2012 at 5:12 PM
    Hi, I´ve been working with phonegap retrieven a ws user data, but for some weird reason when they update info, or anything in the ws response, the app keeps on sending the old response; the only way to get the new response is by uninstalling and installing again the app.

    Any ideas why this could be happening?
  • Commented on 10-03-2012 at 5:42 AM
    I'd have to see more of your code to figure out why it isn't working. SInce your issue really isn't on topic for this blog post, please use my Contact form to send me some details.
  • Miguel #
    Commented on 10-21-2012 at 5:12 AM
    Nice tutorial, Thanks a lot. Ive got a question.
    Do i have to write this:
    var db = window.openDatabase("DDB", "1.0", "DDB", 200000);

    everytime i want to do a query to the database?

    Because when i try to do a query from another html i got nothing I think
  • Miguel #
    Commented on 10-21-2012 at 5:32 PM
    I did it no worries to answer the prevoius question.
    Thanks
  • Anne Spalding #
    Commented on 10-28-2012 at 7:56 PM
    This was not working in IOS because the code
    $("#editPage").live("pageshow", function() {
    var loc = window.location.hash;

    was not retrieving the url parameter. I found another of your blogs (http://www.raymondcamden.com/index.cfm/2012/2/24/G...) which used the data attribute and that fixed the code for me. Just change the var loc line.

    $("#editPage").live("pageshow", function() {
    var loc = $(this).data("url");

    Perhaps this warrants an update to the code?
  • Commented on 10-28-2012 at 8:34 PM
    Thanks Anne. I added a small note towards the end.
  • ad #
    Commented on 11-08-2012 at 11:45 PM
    my error is "Uncaught TypeError: Cannot call method 'transaction' of undefined at file:///android_asset/www/js/main.js:60". so help me... how to slove this error..
  • Commented on 11-09-2012 at 7:00 AM
    @Ad: I'd need more data. It seems like your variable isn't being used correctly. Can you please post your version of main.js to gist.github.com or pastebin?
  • ad #
    Commented on 11-10-2012 at 1:11 AM
    i am new in phonegap.. so i can't get the version of main.js but i am use phonegap-1.1.0.js. i will post my hole main.js to you..
    Thank you to reply me...
  • Aniruddha #
    Commented on 01-09-2013 at 11:49 AM
    Thank you for this tutorial Sir.

    I am just curious as to will it affect performance if we have to execute lots of queries in the table and get their results on app initialization.
    If is it so, is there a better way to counter that.
    I am looking at SQLLite, database.com and PhoneGap storage. Trying to figure out which one suits the best when size of database might cause issues.
  • Commented on 01-09-2013 at 8:57 PM
    Do you really need to execute all those queries on the first load? Maybe some could wait until later - like when some other part of the app is loaded for the first time. That's what I'd do first.
  • Aniruddha #
    Commented on 01-11-2013 at 11:47 AM
    I was thinking on how those jokes/ meme app were created. They get random jokes. Hence, if they have 1000 jokes in record they may be fetching it from DB.
    So, if something on same lines have to be thought for Phonegap, either we will create a DB with those 1000 entries at some point in our application or fetch from already created DB. (Hope I'm assuming right).
    In case if we are loading wouldn't that slow down the mobile app for user, else we are getting from DB, do you have any suggestions on which one works best.

    My apologies for the long comment.
  • Commented on 01-11-2013 at 1:33 PM
    Well, you could try shipping the data with the app (http://www.raymondcamden.com/index.cfm/2012/7/27/G...). Also keep in mind that 1k entries would probably insert pretty darn quickly.
  • Aniruddha #
    Commented on 01-11-2013 at 2:02 PM
    Thank you Sir for that wonderful entry.

    I will use that plugin to work on some demo examples and will see if I could update DB based on user inputs accordingly...
  • Commented on 03-11-2013 at 4:45 PM
    I think you can fake a synchronous executeSql by using a setTimeout loop and have the success and error callbacks do a clearTimeout. Maybe setInterval would even make sense in this scenario because you're just waiting 1 of the 2 callbacks to be called.
  • Commented on 03-11-2013 at 4:47 PM
    Not sure I'd want to do that.
  • pullak #
    Commented on 03-16-2013 at 7:43 AM
    Hi raymond,
    i am new to phonegap. i am using phonegap's cloud build. As u suggest i went through docs about storage. I just want to know, how to give permissions and get started with cloud build ? One Example will be fine.
  • Commented on 03-17-2013 at 6:33 PM
    Sorry, are you about PhoneGap Build? If so, you don't need 'permissions', you just need to register for an account on the site. To get started, read this guide:

    https://build.phonegap.com/docs/start
  • ET #
    Commented on 05-01-2013 at 2:43 PM
    Can you tell me what is the max size of database I can create on IOS device? I read on something like 50MB. Is that correct?
  • Commented on 05-01-2013 at 2:47 PM
    I'm not sure actually. I can say that if you are wanting to store large things, you may wish to use the file system API instead.
  • Jim #
    Commented on 06-20-2013 at 12:18 AM
    Hi, i try to work with phonegap and android sdk, but i have a problem. when i launch my application to my device, samsung Galaxy ace, my app trough a exception.... Uncaught TypeError: Transaction error callback must be of valid type.

    my framework said that the problem occur in the line 75 of my index.html and in this line i do this.

    transaction: function(fn,err,suc){
                if(self.connection==null){
                self.openDataBase();
                }
                self.connection.transaction(fn,err,suc);
             }
    connection is my var where i assig to the database connection.
  • Commented on 06-20-2013 at 9:19 AM
    All I can think of is to ensure that err is really a function.
  • jim #
    Commented on 06-20-2013 at 5:21 PM
    is that right,
    self.connection.transaction(fn,err,suc)......in this invocation i have three function that will pass when used the transaction... i dont know hwat happen, but whe i try the app with the browser, all is right, i can open data base, i can do a select, but when i install the app in my galaxy samsug ace i found this problem, Uncaught TypeError: Transaction error callback must be of valid type.
    do Raymond Camden # have some idea, what is the problem?
  • Jim #
    Commented on 06-20-2013 at 9:35 PM
    thanks for all :) i found the error is my fault
  • Shafi #
    Commented on 07-30-2013 at 4:14 AM
    Hi,

    We are using a set of insert query transactions during a phonegap application launch. Which Takes considerable amount of time. Since all data are in server and that gets frequently updated, we can go for the choice to providing local database file along with the app
  • Shafi #
    Commented on 07-30-2013 at 4:15 AM
    Hi
    We are using a set of insert query transactions during a phonegap application launch. Which Takes considerable amount of time. Since all data are in server and that gets frequently updated, we can go for the choice to providing local database file along with the app

    Is there any better solution that the this? Please help
  • Commented on 08-14-2013 at 9:12 AM
    Hi ! thanks for this post !

    I'd like you could write a tutorial only about handle db transaction from one version to one other.

    Example: after 1 year of development, and in-production, I need to add a column to a table. So my db now is v.2, before was v.1. I'm not able to understand how to handle this ..
    - What happens if my customer download the app from the first time? I suppose I need to init the db directly with v2 code
    - What I a customer had the v1 and after update the db need to be updated to v2 ?
  • Commented on 08-14-2013 at 10:03 AM
    I was writing an answer and this turned out to be more complex then I imagined. Working up a demo for you in a new blog post.
  • Commented on 08-14-2013 at 11:25 AM
    Please see my follow up here: http://www.raymondcamden.com/index.cfm/2013/8/14/U...

    If you have any questions, please post the comment there, not here.
  • Commented on 09-15-2013 at 5:20 PM
    Hello Sir, am new to phonegap but i can use dreamweaver, mysql, php and jquery please Sir i need yur advice on the tools i will need if i want to develop a mobile app to compile using phonegape. infact my major problem is the DBMS engine to use and the server script language kindly provide me with some tips thank you.
  • Commented on 09-15-2013 at 8:18 PM
    Idris, I think you are asking about the tools you need to use PhoneGap. To be clear, there is nothing you have to use. You can use Dreamweaver, Notepad, Brackets, etc. Whatever editor helps you write code is fine for PhoneGap.

    As for the DBMS and server side, PhoneGap doesn't care. My primary experience is with ColdFusion so I've done plenty of blog posts showing CF as the back end, but as I said, PhoneGap doesn't care.
  • Commented on 09-16-2013 at 1:00 AM
    Thanks Sir.
  • armando #
    Commented on 10-09-2013 at 3:38 PM
    Great article; I get an "error loading page" when I submit (save) a note; did anybody fix this issue? thanks.
  • Commented on 10-09-2013 at 4:06 PM
    If you test in Chrome, do you see a better error message?
  • armando #
    Commented on 10-10-2013 at 10:19 AM
    thanks Raymond; I will take a look at it.
  • Commented on 10-11-2013 at 1:07 AM
    I encountered the same problem because there was an error in my javascript. Copy and paste your code to Dreamweaver to check you syntax.
  • Commented on 10-12-2013 at 10:59 AM
    How can I use the results of an executeSql SELECT and Insert them to another executeSql within the same function? I've tried two db.transactions but it seem that the results are not yet known by the last db.transactions even if I assign the results in global variables.

    here's my code:
    function addme(){
    var reni_energy=0;
    var reni_iron=0;
    var db = window.sqlitePlugin.openDatabase('des', '2.0', 'DES DB', 2 1024 1024);
    var sql = "SELECT FROM reni WHERE groupo='" + group + "'";

    db.transaction(function (tx) {tx.executeSql(sql, [], function (tx, results) {
    len = results.rows.length;

    if(len==1){
        reni_energy = results.rows.item(0).energy;
        reni_iron =results.rows.item(0).iron;
    }

       })

    });


    var db = window.sqlitePlugin.openDatabase('des', '2.0', 'DES DB', 2
    1024 * 1024);
    db.transaction( function(tx) {
    var query="INSERT INTO fooditems (energy,iron) VALUES (?,?);";
    tx.executeSql(query,[reni_energy,reni_iron],[],[]);

    });

    }
  • Commented on 10-15-2013 at 1:54 PM
    The callbacks are asynchronous which is why it isn't working for you. You would need to do the insert call inside the callback handler of the select.
  • kasun wickramanayake #
    Commented on 10-24-2013 at 7:23 AM
    Thank u for ur nice tutorial.But i get Following error when i run this programme

    10-24 18:10:52.162: E/Web Console(2974): Uncaught TypeError: Cannot call method 'transaction' of undefined at file:///android_asset/www/js/main.js:60
  • Commented on 10-24-2013 at 8:20 AM
    Keeping in mind this post is now 2 years old - are you using the latest PG? What is line 60 for you?
  • kasun wickramanayake #
    Commented on 10-24-2013 at 10:52 PM
    Yeah i use phone gap 2.9.0.(Codrova 2.9.0).
    Line 60=   dbShell.transaction(function(tx) {
          if (note.id == "")
             tx.executeSql("insert into notes(title,body,updated) values(?,?,?)", [note.title, note.body, new Date()]);
          else
             tx.executeSql("update notes set title=?, body=?, updated=? where id=?", [note.title, note.body, new Date(), note.id]);
       }, dbErrorHandler, cb);
  • Aravinth #
    Commented on 11-19-2013 at 8:55 AM
    it always shows "cannot call method 'transaction' of undefined" in saveData and getEntries.
    i spend full day but this is not solved.
  • Commented on 11-19-2013 at 4:14 PM
    Aravinth: That means the db variable wasn't set right. I'd look into that.
  • Aravinth #
    Commented on 11-19-2013 at 11:58 PM
    Hi Raymond ,

    Thanks for your reply and nice tutorial . i solved that issue it is my fault phonegap version problem so i got that error.

    But now i got another one problem when i click the list view for edit it always empty that is the " window,location.hash" shows empty . Can you tell me what can i do.
  • Commented on 11-20-2013 at 2:41 AM
    Hi Raymond ,

    I am new in phonegap . I use your example in my application. when I tested on device "add notes" is working fine but I try to edit existing notes its shows a message "error loading page"
    Please help me.

    Thanks in advance.
  • Commented on 11-28-2013 at 2:11 PM
    @Aravinth: See if this comment helps: http://www.raymondcamden.com/index.cfm/2011/10/20/...

    @Suraj: You will need to debug to see what the issue is. Try using Weinre and get the line number of the error.
  • Ram #
    Commented on 12-03-2013 at 5:39 AM
    hi sir,

    am developing an phonegap app,the problem am facing is database is created and inserted in all ios and android devices,but not in android 2.3 gingerbread version.is any other possible way to create it?please help me.



    am wating for your reply.
  • Commented on 12-03-2013 at 5:52 AM
    What error do you see?
  • Ram #
    Commented on 12-04-2013 at 12:04 AM
    hi sir,
    am having the following error in android gingerbeard.And also i tried the storage example from the phonegap docs.

    E/Web Console(11914): Uncaught TypeError: Transaction callback must be of valid type. at file:///android_asset/www/index.html:531

    looking for your feed back sir.
  • Commented on 12-04-2013 at 5:10 AM
    Can you show us that line, 531?
  • Ram #
    Commented on 12-04-2013 at 5:22 AM
    sir,

    following is the line which showned in line 531.
    here i pass two parameters for the function parseval which is going to hit api.

    db.transaction(parseval(results.rows.item(k).currentstatus,tx));
  • Commented on 12-04-2013 at 5:31 AM
    That doesn't look valid to me. The first argument in transaction should be an inner function. Please see the WebSQL documentation (http://www.w3.org/TR/webdatabase/).
  • Commented on 12-12-2013 at 11:59 PM
    I have doubt in passing the query result to a variable and displaying that in text box .
  • Commented on 12-13-2013 at 5:58 AM
    Sorry, do you have a question?
  • Commented on 12-16-2013 at 1:18 AM
    Thanks Raymond Camden ,
    This time its work perfectly . I need one more help from you .

    I want to know how can I run phonegap application in the background when I click back button.

    Please help me.
  • Commented on 12-17-2013 at 5:53 AM
    Um - I honestly don't know. I think the OS handles putting an app to sleep based on its logic of how much priority an app needs. I know you have event handlers in PhoneGap you can use (pause/resume), but that's about it.
  • Sandroid #
    Commented on 01-20-2014 at 3:58 AM
    I want to use the UPDATE-Statement in my phonegap application.
    But it doesn't work, i don't know why:

    transaction.execSql("UPDATE PROFILES SET name='SandroidXXX' WHERE id='2'");

    Error 0; The SQLTransactionCallback was null or threw an exception.

    Do you know what the cause of this could be?
  • Commented on 01-20-2014 at 9:17 AM
    Not off hand - can you show a bit more of your code?
  • Aravinth #
    Commented on 03-10-2014 at 2:34 AM
    Hi raymond i have one doubt i googled but didn't find any solution . Please tell me if you know.
    // main.js
    function onDeviceReady(){
       var query = "select * from DEMO";
       transction(query,processPersonsResponse);
    }
    function processPersonsResponse(response){
       alert(response);
    }

    i called the transaction from another JS file like above and i want the return results.
    my another JS file is like:

    function transction(query,a){
       db = window.openDatabase("Database", "1.0", "PhoneGap Demo", 200000);
        db.transaction(
              function(tx){
                 tx.executeSql(query,[],successCB);
        },errorCB);

    }
    function errorCB(e){
       alert("error"+e.message);
    }
    function successCB(tx,results){
       alert(results.rows.length+" db ");
       a(results);
    }

    but i got error like "the statement callback raised anexception or statement error call back".
    Please tell me any idea how to do this.
    Thank you.
  • Commented on 03-10-2014 at 6:16 AM
    I'd have to see it completely to help. Nothing sticks out really.
  • Dina #
    Commented on 05-25-2014 at 7:47 AM
    How could I know if my update statement success or not find the condition and no records updated.
    example:
    UPDATE CUSTOMERS SET customerName= "Tom" WHERE customerId= 1;
    if there is no customerId=1 there will not be any rows affected.

    How could I know the affected rows number in sqlite phonegap cordova 3.4?
  • Commented on 05-25-2014 at 10:17 AM
    The SQLResultSet object supports a property (insertId) for a new ID (if doing an insert) as well as records affected property (rowsAffected). You could use this to determine if data was updated.
  • Dina #
    Commented on 05-25-2014 at 1:33 PM
    could you give me example with update statement ?
  • Commented on 05-25-2014 at 6:11 PM
    The executeSql command lets you specify the call back function to run and the SQLResetSet is passed to it. That should be enough to get you going.
  • Dina #
    Commented on 06-20-2014 at 2:26 PM
    How to display the value of the max id.
    var sql = 'SELECT max(id) FROM CONTACTS';
    var db = window.openDatabase("Database", "1.0", "Demo", 200000);
    db.transaction(function(tx){
       tx.executeSql(sql,[],function(ax,res){
    maxId= res.rows.length;
    }
    it alerts "1" and in table the maximum id =5
    What is the error?
  • Commented on 06-20-2014 at 2:31 PM
    You used the number of rows. It will always be 1 because your SQL returns one row. You want the value of that row, not the number of rows. Try using select max(id) as topId. That will give a name to your column.
  • Dina #
    Commented on 06-20-2014 at 2:59 PM
    could you explain more by my example
  • Commented on 06-20-2014 at 3:28 PM
    I told you what to do. I'm not sure what else I can tell you.
  • Dina #
    Commented on 06-20-2014 at 6:38 PM
    OK i got it
    Many Thanks
  • nehuen #
    Commented on 07-08-2014 at 3:02 PM
    hi, i download you app and works fine, but i need the config.xml file for compile my version for testing, you cand publish it? (I form argentina, sorry for my bad english)
  • Commented on 07-08-2014 at 6:41 PM
    Why do you think you need that?
  • Digvijay #
    Commented on 08-01-2014 at 2:37 AM
    Hi Raymond,

    Thanks for nice tutorial. I tried your code in my android Samsung tab it's not working it was not executing .dbShell = window.openDatabase("SimpleNotes", 2, "SimpleNotes", 1000000);

    Can you please guide it.
  • Commented on 08-01-2014 at 9:06 AM
    What error do you get?
  • Alex Jolig #
    Commented on 10-20-2014 at 4:44 AM
    Hey Raymond. Thanks for your great tutorial. I tried your example and beside that weird error you've mentioned, after I click on "Save Note" button and getting that error. I don't see my added note in the ListView.
  • Commented on 10-24-2014 at 5:27 PM
    @Alex: "that error" - what error?