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Check for status updates using APEX.SERVER.PROCESS

Env: Oracle APEX v5.1.2 with Oracle 12c R2 DB
I have a report that is based off the following table columns in a table called MY_TASK:
TASK_ID (PK),
TASK,
TASK_STATUS (from TASK_CHECKER.task_status)
I also have another table that I use as a running table to check the status of a job that relates to the TASK_ID number from table MY_TASK called TASK_CHECKER which has the columns:
TASK_ID (PK),
TASK_STATUS
Based on the above, I have a scheduled job that regularly checks the status of another table for a specific TASK_ID, which updates the TASK_STATUS value within the TASK_CHECKER table.
Using the above, when the user runs the Oracle APEX app and goes to the MY_TASK report page, I would like through the use of apex.server.process, at startup, join the two tables together via TASK_ID and display the TASK_STATUS at the time within the MY_TASK report.
Please note that the TASK_STATUS values are: WAITING / IN-PROGRESS / SUCCESS or FAILED
So if I had 5 TASK_IDs running, I might see at page load:
1 TASK_A SUCCESS
2 TASK_B ERROR
3 TASK_C IN-PROGRESS
4 TASK_D WAITING
5 TASK_E WAITING
and perhaps 10 seconds later change to:
1 TASK_A SUCCESS
2 TASK_B ERROR
3 TASK_C SUCCESS
4 TASK_D SUCCESS
5 TASK_E IN-PROGRESS
Would like to see TASK_STATUS updates appear in real time.

I just checked and it seems that refresh is async (it doesn't lock the screen). You should be able to do something like this...
setInterval(function() {
apex.region("region_static_id").refresh();
}, 5000);
Just make sure the number of milliseconds is higher than the amount of time the region takes the query to run and the region to render.

Firebase range query

Im using AngularFire+Firebase and have data at firebase-database.
Im trying to paginate Data with Smart Table
My problem is that I dont know how to range query without specifying any child i,e fetch records from record # 25 to 35
Below query gives me first 5 records
var queryFIrst = visitRef.startAt().limitToFirst(5);
$scope.Visits = $firebaseArray(queryFIrst);
now Im trying to get records next 5,from 6 to 10 and I tried below
var queryFIrst = visitRef.startAt().limitToFirst(5).endAt().limitToFirst(5);
$scope.Visits = $firebaseArray(queryFIrst);
but it giving error that startAt and endAt can't be used like this with limit

In general pagination is not a good fit for Firebase's realtime data model/API. You're trying to model a SQL SKIP operator, which won't work with the Firebase Database.
But if you want to model pagination in Firebase, you should think of having an "anchor point".
When you've loaded the first page, the last item on that page becomes the anchor point. When you then want to load the next page, you create a query that starts at the anchor point and load n+1 item.
In pseudo-code (it's real JavaScript, I just didn't run it):
var page1 = visitRef.orderByKey().limitToFirst(5);
var anchorKey;
page1.on('child_added', function(snapshot) {
anchorKey = snapshot.key; // this will always be the last child_added we received
});
Now when you want to load the next page of items, you create a new query that starts at the anchor key:
var page2 = visitRef.orderByKey().startAt(anchorKey).limitToFirst(6);
A few things to note here:
You seem to be using an approach from the Firebase 1.x SDK, such as an empty startAt(). While that code may still work, my snippets use the syntax/idiom for the 3.x SDK.
For the second page you'll need to load one extra item, since the anchor item is loaded for both pages.
If you want to be able to paginate back, you'll also need the anchor key at the start of the page.

Is that what you needed that time?
visitRef.orderByKey().startAt("25").endAt("35")
I asked a similar question Get specific range of Firebase Database children

Lightswitch load all data or run a async method synchronously

I have a grid with data in Lighswitch application. Grid has on every column posibility to filter column. Thanks to lsEnhancedTable
Right now I am sending an ajax request to the web api controler with the list of ids of the Customers that I want to export. It works but with a lot of data it is very slow because I have to turn off the paging of the data to get all visible customers ids so I can iterate over the VisualCollection.
To optimize this I would have to turn on back the paging of the data to 50 records so that the initial load is fast and move the loading of the data to a save/export to excel button.
Possible solutions:
Load data all data on save button click. To do this I have to somehow load all items before I can iterate over collection.
The code bellow locks UI thread since the loadMore is async. How to load all data synchronously? Ideally I would like to have some kind of progress view using a msls.showProgress.
while(3<4)
{
if (screen.tblCustomers.canLoadMore) {
screen.tblCustomers.loadMore();
}
else
break;
}
var visibleItemsIds = msls.iterate(screen.tblCustomers.data)
.where(function (c) {
return c;
})
Second approach would be turn on paging and pass just the filters applied by the users to the web api controller so I can query database and return only filtered records. But I don't know how to do that.
Third approach is the one that I am using right now. Turn off the paging->iterate over visual collection, get the customers id, pass them to the controller and return a filtered excel. This doesn't work well when there are a lot of records.
Iterate over filtered collection in the server side? I don't know if there is a way to do this in Lighswitch?

Here's an option for client side javascript.
// First build the OData filter string.
var filter = "(FieldName eq " + msls._toODataString("value", ":String") + ")";
// Then query the database.
myapp.activeDataWorkspace.ApplicationData.[TableName].filter(filter).execute().then(function (result) { ... });

Simple pagination for jquery after ajax success of php select

I want to paginate the result of my ajax success. In my ajax when I get success I append all result into one table (this table is empty by default only header).
I used this tutorial but I can't figure out how to make it work when the table is empty by default. I was able to make it run when there are values by default.
When the table is populated after ajax success nothing is happening to the data all are displayed. Is there a more applicable sample or tutorial for this kind of scenario. Or what needs to be done on the current tutorial to make it work.
Any suggestion is appreciated

You shouldn't use pagination this way, I suggest you to make your function returning only the records needed for the selected page.
It's useles to make your ajax return all the set (ej. 300 rows) if you are only going to show only a subset (ej. 30 rows in page 1). So you should add to the function which return the records from the DB (lets call it getRecords) a few parameters more:
page: the current/selected page of the paginator
records: how many records you want to show in each page
Combining this two you can limit your sql accordingly, f.instance (you can prepare the limit and the offset before the call in your php code):
select blablabla from blablable where blablablu
limit records, offset (page * records)
note: the first page here is zero. So for the first page the first record will be 0 and the last record shown will be 30 (this is (0 + 1) *30).
Here you have a good tutorial.

ajax with database query and show/hide table rows

I am building a simple website for a project. One of my page do MySQL database query and output all contents to a html table, I then use a filter enable uses to show/hide certain rows.
This strategy works well when deal with hundreds of rows, but when dealing with thousands of rows, there is a significant delay when people clicking the link. I thought might be I could add some Ajax, display a 'loading/querying' information when the query didn't finished.
A sample webpage: http://epigenome.wustl.edu/TE_Methylation/browse.php
When people go to that link, before database finished query, I want to display a 'loading' message, and also when people choose to hide several rows, before the Javascript finished hide the corresponding rows, also display a 'loading' information.
(The example page above didn't have this issue because there are only 900 rows, while I am working on a dataset with 10000+ rows)
Did anyone have some suggestions on how to achieve this? many thanks :)

When working with a large amount of data, you want to try and filter as much of that data before you send it to the client. Imagine that your viewer is on a mobile device or limited connection speed. This data will take even longer to transfer.
What I would do in your case, is set up an ajax service that responds with a json list of results for a given filter / criteria. I would then limit the response to a page or range as was stated in comments.
So, filter your results in your MySQL query using parameters provided via an Ajax request.
For example (a load more example)
var dataService = function() {
this.Loaded = 0,
this.Limit = 20,
this.LoadMore = function() {
$.getJSON("data_service.php", { FilterH1ES : true, Blah : true, Start : this.Loaded, Limit : this.Limit }, function(results) {
// Append Rows to table
// ...
}
}
}
// OnLoad call dataService.LoadMore();
Then in PHP, you would do the query filters for MySQL based on the parameters.
<?php
$filters['H1ES'] = $_GET['FilterH1ES'];
$sql = "SELECT * FROM MyTable WHERE /* Default Filter Here */";
if ($filters['H1ES']) $sql .= " H1ES Filter";
// ... run query and json_encode(result);
Code is not tested and my javascript is rusty.