The LIKE operator is a very useful one. It is used to match strings with partial match while using the underscore (‘_’) as a single character wildcard and the percentage sign (‘%’) as multiple character wildcard.
When writing a query with order by, we can use the column position instead of its name. This order by”trick” is easy to use, but should be handled carefully as it affects the order of rows if the column list changes.
Many people are using DBMS_STATS to gather optimizer statistics. This package has many different options, and I wanted to tell you about one option for disabling automatic statistics gathering. When we need to disable the automatic statistics gathering we usually do one of the following:
When user A creates a procedure and grants execute permissions to user B, user B can execute the procedure (obviously), but he can also see the code (in ALL_SOURCE view).
If you are using Data Guard and standby databases, you probably need to do stuff based on the database role. For example, have some services start on the primary database, whichever that is. You might want to update some tables upon failover/switchover and more.
Oracle database is a very complex software, and as we all know, has bugs. Oracle tries to address these bugs, and fixes a lot of them all the time. Except specific fixes, they publish patchsets (which might introduce more than only bug fixes) and PSUs. If you are not aware of these patch types and how it works, you are welcome to read my post about it here.
Many of my clients use storage backup (snapshots, etc.) to backup their databases. The right and supported way to do that is like any hot backup: place the database in backup mode, take the snapshot, take the database out of backup mode, archive the current logfile and backup the archives, right?