I am trying to update a table in an Phonegap Cordova App using Web SQL.
Following is the function that i have built for updating record but it is not updating the database nor giving any error.
function updatedrink(x, y, z) {
alert(x);
alert(y);
alert(z);
db = window.openDatabase("smartbar", "1.0", "Smart Bar", 10000);
db.transaction(function (tx) {
tx.executeSql("UPDATE drinks SET name=?, qty=? WHERE pos=?", [y, z, x], function(tx, result) {
alert('Updated');
}, function(error) {
alert(error);
});
});
}
All the alert statements are giving the correct values but table is not updated. No matter how much i try i cannot point out a single mistake. Please rescue.
I trying to get the value (true or false) from nested functions inside of a method, but value returns UNDEFINED. How I can get a value from a object nested function?
var result = {
compute: function() {
this.retorno = result.transaction();
},
transaction: function() {
var db = window.sqlitePlugin.openDatabase({name: 'database.db', location: 'default'});
db.transaction(checaFR,erroFR); //Check if (F)irst (R)un.
function checaFR(tx){ //Check if table exists
tx.executeSql('SELECT * FROM setup',[],checaFRSuccess,erroFR2);
alert("Select Query OK");
}
function erroFR(err){ //Return if error
alert('Ops - '+err);
return false; //This value I Need! :(
}
function checaFRSuccess(tx,result){
alert("Query Sucess "+result.rows.length);
return ('Rows: '+result.rows.length);
}
function erroFR2(err2) { //If no DB table
alert("erroFR2: "+JSON.stringify(err2));
db.transaction(populateDB, errorCB, successCB); //Start DB Populate
}
function populateDB(tx) {
tx.executeSql('CREATE TABLE IF NOT EXISTS setup (id INTEGER PRIMARY KEY AUTOINCREMENT, runned TEXT NOT NULL)');
tx.executeSql('INSERT INTO setup(runned) VALUES ("1")');
}
function errorCB(errCB) {
alert("Error processing SQL: "+errCB);
return false; //This value I Need! :(
}
function successCB() {
alert("successCB OK");
return true; //This value I Need! :(
}
}
};
result.compute(); //Start the main function
return {
retorno: "var: "+result.retorno //This returns UNDEFINED
};
How I can get the value from this function and pass it?
Note: All callbacks and alerts are working, including the database creation. :D
You can refer to the function nested inside using the following code.
result.transaction().erroFR();
result.transaction().errorCB();
But before that you need to return the Object from the inner function which needs to be publicly accessible. This is basically a module pattern, where you can expose only the relevant information to outside world. So you need to expose the functions as shown below. Note the return statement at the end of the function which is returning an object.
var result = {
compute: function() {
this.retorno = result.transaction();
},
transaction: function() {
var db = window.sqlitePlugin.openDatabase({name: 'database.db', location: 'default'});
db.transaction(checaFR,erroFR); //Check if (F)irst (R)un.
function checaFR(tx){ //Check if table exists
tx.executeSql('SELECT * FROM setup',[],checaFRSuccess,erroFR2);
alert("Select Query OK");
}
function erroFR(err){ //Return if error
alert('Ops - '+err);
return false; //This value I Need! :(
}
function checaFRSuccess(tx,result){
alert("Query Sucess "+result.rows.length);
return ('Rows: '+result.rows.length);
}
function erroFR2(err2) { //If no DB table
alert("erroFR2: "+JSON.stringify(err2));
db.transaction(populateDB, errorCB, successCB); //Start DB Populate
}
function populateDB(tx) {
tx.executeSql('CREATE TABLE IF NOT EXISTS setup (id INTEGER PRIMARY KEY AUTOINCREMENT, runned TEXT NOT NULL)');
tx.executeSql('INSERT INTO setup(runned) VALUES ("1")');
}
function errorCB(errCB) {
alert("Error processing SQL: "+errCB);
return false; //This value I Need! :(
}
function successCB() {
alert("successCB OK");
return true; //This value I Need! :(
}
// Return an object containing functions which needs to be exposed publicly
return {
checaFR : checaFR,
erroFR : erroFR,
checaFRSuccess : checaFRSuccess,
erroFR2 : erroFR2,
populateDB : populateDB,
errorCB : errorCB,
successCB : successCB
}
}
};
You need to pass a callback function into the result.transaction method, and the false value would be passed into that callback function.
You have to do this bc false is derived during/after db.transaction, which is an asynchronous method... so we have to pass false asynchronously as well.
I have a working PhoneGap database transaction where I am able to run a sql query and process the results. However, in an effort to make it reusable, I need to be abe to pass arguments to the querying function. There should a better way than declaring global variables and accessing them/resetting in the query function. Appreciate any help in converting this:
//update images function
function updateGalleryCovers() {
var db = window.openDatabase("test db", "1.0", "Cordova DB", 200000);
db.transaction(queryDB_u_g, errorCB);
}
//Query the database
function queryDB_u_g(tx) {
var query = 'SELECT cover_img, objectId FROM USER_GALLERY WHERE userId="'+getUserId()+'"';
tx.executeSql(query, [], querySuccess_u_g, errorCB);
}
//Query success callback
function querySuccess_u_g(tx, results) {
var len = results.rows.length;
for (var i=0; i<len; i++){
// process results
}
}
to something like this:
//update images function
function updateGalleryCovers(userid) {
var db = window.openDatabase("test db", "1.0", "Cordova DB", 200000);
db.transaction(queryDB_u_g, userid, errorCB);
}
//Query the database
function queryDB_u_g(tx, userid) {
var query = 'SELECT cover_img, objectId FROM USER_GALLERY WHERE userId="'+userid+'"';
tx.executeSql(query, [], querySuccess_u_g, errorCB);
}
//Query success callback
function querySuccess_u_g(tx, results) {
var len = results.rows.length;
for (var i=0; i<len; i++){
// process results
}
}
Thanks!
The transaction functions are offered by sqlite and not phonegap. Its true that you can't pass extra variables to the functions because of the method signature sqlite accepts.
But here's a work around for the same:
db_conn.transaction( function(tx){ your_function(tx, parameter1, parameter2) }, ErrorCallBack );
Here you are passing a dummy function to the transaction success callback and taking the transaction object along with it.
Hope that helps
Is there any example of js accessing device's (ios and android) sqlite db via Trigger.io?
The normal web database API is available: http://www.w3.org/TR/webdatabase/
Note: not all browsers support Web SQL http://caniuse.com/#feat=sql-storage
For example, one of the tests we run is similar to this:
var db = openDatabase('mydb', '1.0', 'example database', 2 * 1024 * 1024);
db.transaction(function (tx) {
tx.executeSql('CREATE TABLE IF NOT EXISTS foo (id unique, text)');
tx.executeSql('INSERT INTO foo (id, text) VALUES (1, "foobar")');
});
db.transaction(function (tx) {
tx.executeSql('DROP TABLE foo');
// known to fail - so should rollback the DROP statement
tx.executeSql('INSERT INTO foo (id, text) VALUES (1, "foobar")');
forge.logging.error("INSERT into non-existent table succeeded!");
}, function (err) {
forge.logging.info("error callback invoked, as expected");
});
db.transaction(function (tx) {
tx.executeSql('SELECT * FROM foo', [], function (tx, results) {
forge.logging.info("row: "+results);
});
});
Nowadays you should use something like LocalForage as this fallsback through indexedDB to webSQL to localStorage for you, plus gives you a consistent api. And if you are using Angular/Ionic then this is the business: Angular-LocalForage
From a tutorial code like this
function queryDB(tx) {
tx.executeSql('SELECT * FROM DEMO', [], querySuccess, errorCB);
}
function querySuccess(tx, results) {
}
function errorCB(err) {
alert("Error processing SQL: "+err.code);
}
var db = window.openDatabase("Database", "1.0", "PhoneGap Demo", 200000);
db.transaction(queryDB, errorCB);
in db.transaction i want to pass a variable as argument to queryDB function, so the code which i think of should looks like
db.transaction(queryDB(id), errorCB);
How I can actually implement this ? Or its simply gonna work like this and my id will be passed and get in tx ?
Wrap it in a function again
var id = 'THEID';
db.transaction(function(){
queryDB(id)
}, errorCB);
Note - This is assuming that you're making the API. Some APIs / frameworks insert the required information automatically. For example
//the db.transaction method
function transaction(param, callback) {
//do code stuff
callback(someInternalId); //callback is the function you pass as the first parameter
}
So, if you want to pass your own data in the callback, wrap it in a function. Otherwise, the code you are using may be doing this for you automatically.
I like to keep things very simple so I use a limited number of functions when handling storage on phonegap applications that can receive parameters. A lot of the examples I have seen have calls to many sub functions and for me, this is a nightmare when it comes to debugging.
I was caught out an a number of issues around Web SQL but reading the specs really, really helped clarify what I could and couldn't do. (http://www.w3.org/TR/webdatabase/)
Look at this simple code for an insert function:
function dbInsert(param1, param2, dbObj) {
val1 = param1;
val2 = param2;
val3 = String(dbObj.item2);
var sqlTxt = "INSERT INTO demo (geo1, geo2, geo3) VALUES (?, ?, ?)";
db.transaction(function(tx) {tx.executeSql(sqlTxt,[val1,val2,val3])}, errorCB, successCB);
}
Lets just to walk through it. Obviously a standard function which receives parameters which can be anything, in this case an object as well a strings.
sqlTxt is where the fun begins. Write this as you would normally write an insert statement, but where you would normally have the data to be inserted/selected etc in VALUES use the ? placeholder for each field in the database tables you want to pass data into.
Now lets break down the next line:
db.transaction(function(tx) {tx.executeSql(sqlTxt,[val1,val2,val3])}, errorCB, successCB);
When you create a new database, db is the handler to the database object so db.transaction asks to execute a transaction on the database db.
If we write next next section like this you can see it's function that calls tx.executeSql and because it in execute inside the db.transaction method, it will be passed the db handle.
function(tx) {
tx.executeSql(sqlTxt,[val1,val2,val3])
}
Now if we were to parse the sqlTxt it might look like this
INSERT INTO demo (geo1, geo2, geo3) VALUES ('a', 'b', 'c');
and because we are passing the three variable in place of the ? holder, it looks like the line above. And finally you call error and success callback functions.
In your case I would create a queryDB function like this:
function queryDB(id) {
var sqlTxt = "SELECT * FROM DEMO WHERE id=?"
db.transaction(function(tx) {tx.executeSql(sqlTxt,[id])}, errorCB, successCB);
}
In essence, the function grabs the parameter id, passes it into the query in the [id] and executes and returns error or success. Obviously you can extend this to use multiple parameters or if you want to be really clever, you just create a single database transaction function and pass in the sql and the parameters to use as an object or array (Example will be on my blog this weekend)
Ok first of all create a class hat will handle you're db instances (db updates etc) this class will hold a function that you will use for all you're query's
self.db = window.openDatabase( // and so on
then the function:
// execute a query and fetches the data as an array of objects
self.executeQuery = function(string, args, callback, callbackparams) {
var self = this;
//console.log('db execute: '+string);
self.db.transaction(function(tx) {
tx.executeSql(string, args, function(tx, result) {
var retval = [];
for (var i = 0; i < result.rows.length; ++i) {
retval.push(result.rows.item(i));
}
if (callback) {
callback(retval, result, callbackparams);
}
}, self.error);
});
}
then when u have initiated you're class (i named it myDb) go apeshit!
myDb.executeQuery('select l.* from location l inner join item_location il on (il.location_id = l.id and il.item_id = ?)', [item.id], function(locations, res, item){
item.locations = locations;
myDb.executeQuery('select * from media where item_id = ?', [item.id], function(media, res, item){
item.media = media;
// create item.
createItem(item);
}, item);
}, item);
as you can see the executeQuery has 4 params,
query,
params for query,
callback (with 3 params, result, status and myparam)
myparam (for callback)
It took me some time to fix this, but when you've done this! no more annoying db horror!
We can't send any paramenter for queryDB function like "queryDB(id)"
I solved this issue by this way.
var contactId = 33
dbInst.transaction(function(tx){
tx.executeSql('CREATE TABLE IF NOT EXISTS CONTACT_REFERENCE (id unique)');
var sqlStr = 'INSERT INTO CONTACT_REFERENCE (id) VALUES (?)'
tx.executeSql(sqlStr, [contactId]);
}, errorCB, successCB);
I think everyone comes close to answering your question. Really you need one slight modification to JohnP's answer. You should pass in the SQLTransaction Object that carries the executeSQL function. So to build on John's answer:
var id = 'THEID';
db.transaction(function(tx){
queryDB(tx, id)
}, errorCB);
Then where you define the function you can grab your id param with an extra variable.
queryDB: function (tx, id) { ...your code... }
This is a worked solution:
var sqltxt= 'INSERT INTO CONTACTS(id, data) VALUES (?, ?)';
var db = window.openDatabase("Database", "1.0", "Demo", 200000);
db.transaction(function(tx){tx.executeSql('DROP TABLE IF EXISTS CONTACTS');
tx.executeSql('CREATE TABLE IF NOT EXISTS CONTACTS(name unique, password)');
tx.executeSql(sqltxt,[name, pass]);
}, errorCB, successCB);