AND vs. OR in queries
The Join field in the Query Builder provides connectors for joining rules (AND, AND NOT, OR, OR NOT). The effect of AND versus OR in the Query Builder may not be obvious at first glance.
In essence, AND and OR work in this way:
AND limits or restricts the scope of the query.
OR opens up the query to an additional possibility, expanding the scope of the query.
Note: Do not use AND to join the rules that are intended to include additional virtual machines in the backup list. For instance, AND cannot be used to mean "include virtual machine X AND virtual machine Y."
For example: To include the virtual machines that have either "vm1" or "vm2" in their names, use OR to join the rules:
Displayname Contains "vm1" OR Displayname Contains "vm2"
If you use AND to join these rules:
Displayname Contains "vm1" AND Displayname Contains "vm2"
the result is different: the backup list includes only the virtual machines that have both vm1 and vm2 in their names (such as "acmevm1vm2"). A virtual machine with the name "acmevm1" is not included in the backup.