Generally, we will have 3 types of rules(either in alert/event rules) in cloud they are builder rule, SQL rule, placeholder rules.

In SQL type rules, when ever there is a data match to particular query , that rule gets triggered & hence we will be getting either alert for alert rule or detection for event rule. These can be customized.

The 2nd type of rules are Cloud Builder rules, For builder rules we need to mention the table ,column value to look out for . Unlike SQL type here we will get alerts only when there is any recent change in the data. The rule engine will fetch the results for the table, column that the rules it is looking for daily. But the rules get triggered (it evaluates ) only when there are any changes in the daily results that it is getting. So, this particularly highlights the efficiency by triggering alerts/event only on relevant data changes. There are some exceptions in it like whenever in the builder rule the column the table is looking for involves date& time.

For placeholder rules, these are some type of special rules. Whose alerts are generated programmatically. They are too complicated to be represented as builder OR SQL rule, hence this 3rd type of rule. These are not displayed in the UI.  It can't be customized like other rules.