Hi Soumya,

A Fast Update saves changes to sObject variables and sObject collections. A Record Update saves information from variables and other flow resources, such as screen input fields, directly to one or more records in the database.

With Record Update you'll be updating fields with values from your flow and you necessarily have the values that have already been stored to the records. Record Update makes changes to all the records you specify in your filter. This is a powerful element, so be careful that you filter to just the records you want or you'll end up writing to more records than you anticipated.

Wth Fast Update, on the other hand, you'll most likely have looked up the record(s) that you want to change so you will not only have your variables and other flow resources with which to make changes, but you'll also have the existing field values to do calculations and make decisions before you make those changes.

For instace, Let's say you want to set a text field called "Division" to "SingleDivision." You know that you want to make that change on all account records who's number field "ActiveEEs" is equal to 1 and text field "Division" is empty. You don't have to look up records, make changes to them, then re-save them. Instead you can use a single Record Update element where you specify your filter criteria, and then enter the values for the fields that you want to update.



A Fast Update, on the other hand, requires that you have either an sObject variable or an sObject collection that will be used to update records in the database. These are usually obtained via a Fast Lookup, but you can also create sObjects by scratch. By scratch is harder so I wouldn't really recomment it, but if this is what you're doing, you'll also need to be saving the Ids of the records you want to update.

What you will typically do is use a Fast Lookup to locate your record (or records). You'll then change the field values of the sObject variable using an assignment element, and finally will use a Fast Update to save your changes.



So both can be used to update single or multiple records, but if you need to do manipulations to the records based on information already contained in the record you'll want to do a Fast Lookup, do your stuff, then do a Fast Update. However, if you just need to update some values, and you know you can filter to just the records that need to update, a Record Update is a super sleek choice.

Personally I almost always use the Fast elements as I am usually making changes based on fields values already saved to the records. I'm also often working with collections of sObjects, and a Fast Update is the perfect tool for updating an entire collection all at once. (I've also had times where I used a Record element, then at a later stage had to change to a Fast element and found it to be a ton of work to make the change.) I will add, though, that I love the sleekness of the Record elements with simple, straightforward processes and don't shun using them in the appropriate places.