OOW2012 - PL/SQL Enhancements in Oracle 12c

So what's planned for the upcoming 12c database regarding PL/SQL? What follows is a list of what are presented as the most important changes...

Improved PL/SQL - SQL interoperability

You don't need to specify the type at the schema level when you want to use it SQL, specification at the package level is sufficient and you can bind it to SQL directly;
Get the performance of SQL with the clarity and reusability of PL/SQL by adding a pragma UDF to a schema level PL/SQL function - almost as fast as pure SQL;
You can declare a PL/SQL function in the WITH clause of a subquery: with function x(param) <body> end x; select x(p) from t;
Using the "with" construct is 3.8x faster than using an old fashioned PL/SQL function, function with pragma is 3.9x faster, pure SQL is 5x faster.

A new security capability

Grant access to a PL/SQL unit by granting a role to a PL/SQL unit, where the role contains the required rights for accessing the tables - so a function can only select, update etc from a table where it has been granted access to.

Improved programmers usability

New package UTL_CALL_STACK for better display of errors (with functions like dynamic_depth(), unit_line(), subprogram(), concatenate_subprogram(), owner(), current_edition(), lexical_depth());
You can whitelist units that can reference a particular unit to prevent unwanted calls: add "accessible by (proc1, proc2)" to the unit definition.

Comments

astramieri said…

Hi Roel!
Thanks for sharing this.
Do you know where I can find a complete (reliable ?) list of PL/SQL enhancements in Oracle 12c ?
A.

4:35 pm

Roel said…

I guess around the time 12c will be generally available. Not much sooner, not much later....

4:50 pm

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 ...

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 o...

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 ...

Roels Blog

Search This Blog