Skip to main content

EECS - Oracle Exadata Express Cloud Service, Step 2

Once you get your services up and running, you can log into your domain - in this screenhot "smart4apex" - on the Oracle Cloud.
Then you'll end up in the "My Services" dashboard. As I have only one, my dashboard looks quite clean, showing just this widget:
Just a few remarks for the designers of this: I am very curious why there is an extra "(Number of ..." in the chart title. The same superflous text is also on another location on that page.
And, more intriguing, what would "0.0323 database instances" mean? 1/0.0323 = 31. So something like days? But February has 28 days...
It would make way more sense to just show here how many instances I had on those day (so, "1" al over the place...).
From this widget you can drill into the "Service Details", where you can set rules and alerts and see the (historical) status of your instance. Funny thing is, I noticed this:

These figures indicate, I have a storage limit of 23Gb. But my service is based on 20Gb. So I get 3Gb "for free"!
Probably that's (more or less) used by Oracle itself (SYS, APEX etc.). So if you buy 20Gb, you really get 20Gb to store your own data!
Now it is time to add some users to this instance. As we - as smart4apex - would like to use it as a development environment, I added all colleagues as a user. 
And i can assign Roles to every user. There is a standard list of roles defined. From the documentation I figured out that the first two are entitled to add or modify other users, but what the privileges and restrictions of the other three are, I still have to discover. What I do know is, if you just assign the "Database User" role to a user, you can log in to the My Services page, but if you try to use the Exadata Express service, you get an "Acces Denied" message. You need at least Database Developer or Database Administrator to access the APEX builder (more about that in a later post).
A nice feature is, you can upload a csv file to create multiple users and assign roles in batch. Saves you a lot of clicks....
And every user you create receives a nice welcome email with a temporary password and a login link. Once you use that link, and login you end up on a (rather outdated - ADF faces built) page of Oracle Identity Self Service to change your password and register three (!) challenge questions. That is a challenge in itself ;-)
Apart from the standard Roles, you can define "Custom Roles" and assign those to users. But any information about how to use these roles in an APEX application is welcome, as I couldn't find any documentation on this subject.

In the next post, I'll go into the database (in)side of the service and in the subsequent one, the APEX development environment of the Exadata Express Cloud Service (EECS).

Comments

Popular posts from this blog

Filtering in the APEX Interactive Grid

Remember Oracle Forms? One of the nice features of Forms was the use of GLOBAL items. More or less comparable to Application Items in APEX. These GLOBALS where often used to pre-query data. For example you queried Employee 200 in Form A, then opened Form B and on opening that Form the Employee field is filled with that (GLOBAL) value of 200 and the query was executed. So without additional keys strokes or entering data, when switching to another Form a user would immediately see the data in the same context. And they loved that. In APEX you can create a similar experience using Application Items (or an Item on the Global Page) for Classic Reports (by setting a Default Value to a Search Item) and Interactive Reports (using the  APEX_IR.ADD_FILTER  procedure). But what about the Interactive Grid? There is no APEX_IG package ... so the first thing we have to figure out is how can we set a filter programmatically? Start with creating an Interactive Grid based upon the good old Employ

apex_application.g_f0x array processing in Oracle 12

If you created your own "updatable reports" or your custom version of tabular forms in Oracle Application Express, you'll end up with a query that looks similar to this one: then you disable the " Escape special characters " property and the result is an updatable multirecord form. That was easy, right? But now we need to process the changes in the Ename column when the form is submitted, but only if the checkbox is checked. All the columns are submitted as separated arrays, named apex_application.g_f0x - where the "x" is the value of the "p_idx" parameter you specified in the apex_item calls. So we have apex_application.g_f01, g_f02 and g_f03. But then you discover APEX has the oddity that the "checkbox" array only contains values for the checked rows. Thus if you just check "Jones", the length of g_f02 is 1 and it contains only the empno of Jones - while the other two arrays will contain all (14) rows. So for

Stop using validations for checking constraints !

 If you run your APEX application - like a Form based on the EMP table - and test if you can change the value of Department to something else then the standard values of 10, 20, 30 or 40, you'll get a nice error message like this: But it isn't really nice, is it? So what do a lot of developers do? They create a validation (just) in order to show a nicer, better worded, error message like "This is not a valid department".  And what you then just did is writing code twice : Once in the database as a (foreign key) check constraint and once as a sql statement in your validation. And we all know : writing code twice is usually not a good idea - and executing the same query twice is not enhancing your performance! So how can we transform that ugly error message into something nice? By combining two APEX features: the Error Handling Function and the Text Messages! Start with copying the example of an Error Handling Function from the APEX documentation. Create this function