Performance of APEX Conditions
Just a little tip I picked up at the InSync13 conference from listening to Scott Wesley. If you have a lot of conditions that look like this:
(conditions based on a PL/SQL Expression, where the PL/SQL itself doesn’t actually call anything outside of APEX – it’s only dependent on variables that Apex already knows)
Because it’s a PL/SQL expression, the APEX engine must execute this as dynamic PL/SQL – requiring a parse/execute/fetch. This might take maybe 0.03 seconds or so. If there’s only one condition like this on a page, it won’t make any difference. But if there are 50 conditions on a page, it can make a difference to the overall page performance – adding up to 1 whole second or more to the page request, which can be noticeable.
The better alternative is to use the condition type Value of Item / Column in Expression 1 = Expression 2, e.g.:
This condition type requires no dynamic PL/SQL – no parsing – which can reduce the time required to an almost negligible amount.