Salesforce Fact #933 | Query row count for parent to child soql

The query rows count is a bit different in case of SOQL with parent to child subquery.

For example, if there are 5 accounts each having 2 contacts in the org, then the below query would return 15 query rows while calling Limits.getQueryRows():

[SELECT Id, (SELECT Id FROM Contacts) FROM Account] i.e. total number of accounts + total number of contacts with related accounts

Reference: https://salesforce.stackexchange.com/questions/184131/what-is-the-limit-for-subquery-in-soql