How do processes consume SOQL queries?

Question

I'm currently using processes to update records. The ills describing of using the process builder are known to me, but I need more information on how 'Update Record actions' in a process are bulkified.

The official Salesforce documentation says that "Each Update Records action uses one SOQL query and one DML statement." Is this per record or per DML transaction that fired the process?

Example: If inserted 10 cases that match the criteria for a process with an Update Action, would I expect to see 1, 10, or some other number of soql queries & DML operations consumed?

Answer 1

It's one DML and SOQL per 200 records or a single DML "chunk."

To illustrate this, consider the following code:

contact[] c = [select id from contact limit 5];
id accountid = [select id from account where ispersonaccount = false limit 1].id;
c.add(new contact(lastname='test1', accountid=accountid));
c.add(new contact(lastname='test2', accountid=accountid));
c.add(new contact(lastname='test3', accountid=accountid));
c.add(new contact(lastname='test4', accountid=accountid));
c.add(new contact(lastname='test5', accountid=accountid));
upsert c contact.id;

Here, we have two upsert chunks; we're updating five records and inserting five more, all in one DML statement. I've purposefully turned off everything else in my org except a single process builder that updates the account with the contact's name. The logs end up looking like this:

  Number of SOQL queries: 4 out of 100
  Number of query rows: 11 out of 50000
  Number of SOSL queries: 0 out of 20
  Number of DML statements: 3 out of 150
  Number of DML rows: 20 out of 10000

The code I wrote uses the following limits:

  Number of SOQL queries: 2 out of 100
  Number of query rows: 6 out of 50000
  Number of SOSL queries: 0 out of 20
  Number of DML statements: 1 out of 150
  Number of DML rows: 10 out of 10000

Activating the process added 2 more queries, 5 more query rows, 2 more DML statements, and 10 more DML rows. My DML statement is an upsert, which it decided were five inserts and five updates, so two "chunks." Apparently, only 5 records were queried, because we went from 6 to 11 rows queried, 2 additional queries were issued, 2 DML statements resulted from the two chunks, and 10 more rows were added (one for each original row in DML statement).

As you can therefore conclude, it is 1 query and 1 DML statement per chunked transaction. Keep in mind that you're also charged for query rows and DML rows accordingly.