May 2019
Intermediate to advanced
546 pages
12h 41m
English
Content preview from Salesforce Platform Developer I Certification Guide
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Trigger.old
This returns a list with the old version of the records. This variable returns a list of sObjects, so if you want to use properties of a specific object type (such as Account), you need to cast your list to a list from the specific object. This variable is only available in the following contexts:
- Before and after an update
- Before and after delete:
List<Account> lstAccounts = (List<Account>) Trigger.old; // the list 'SObject' is casted to a list with 'Account' records
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.