Hi, Today, I needed to list all blocking sessions hierarchically. As you know, all information about sessions (and blocking sessions) are in gv$session (or just v$session if you are using single instance) view. I wanted to see who is blocking who and blocker at the top. you can write simple connect by (or with clause)
Administration
Enable Unified Audit on Linux and Windows
Hi, As you know, since 12c Oracle introduce Unified Auditing which has much more capabilities than standard auditing. Creating policies, audit conditions, top level auditing etc. By default Oracle uses “mixed” mode which allows you to run unified auditing commands and standard auditing. you can check if you are using unified auditing by default:
Blockchain vs Immutable tables
Hi, as you know 21c is here for linux and some new features are (as always) pretty exciting. two of them are Blockchain and Immutable tables. Let’s explain and test. first of all, those are new features for 21c but they are backported to 19c. at 19.10 you are able to use BLOCKCHAIN tables and
ORA-00600 [kzan_open_osfile:ksfdread] while querying/purging unified audit
Hi everyone, Lately, I hit and ORA-600 while querying unified_audit_trail on 19.8 Oracle database and same thing happens if you want to purge audit data too. the exact error message is: ORA-00600: internal error code, arguments: , , , , , , , , , , , Normally, I check the support first but
X Forwarding for an Oracle DBA
Hi, It’s been a long time. I want to write something about X Forwarding. you might feel more comfortable to use a GUI instead of silent installations sometimes. if you are connecting to a linux server remotely then you must enable X Forwarding to enable GUI for Oracle product like dbca, netca etc. First of
Create a Clone DB from Backup on the Same Server (or remote)
Hi, I wanted to create a post series about cloning/duplicating database on the same or remote servers. There are so many options and combinations about this like rman duplicate database with/without target/source db connection, rman restore using backups, ASM to OS or OS to ASM, same server or remote server, OMF or regular file naming
Pragma UDF & Deterministic
Hello everyone, I wanted to write about something simple and can improve the performance of your sql statements. Unfortunately, many database developers use too much plsql function in their SQL statements. I say too much because if you learn more about the SQL, you will use less plsql. SQL is very capable language to process
PLSQL and Flashback Data Archive Problems.
Hi, I have written about flashback data archive before. if you didn’t read please check these post first. http://mustafakalayci.me/2019/03/02/goodbye-log-triggers-welcome-flashback-data-archive/ http://mustafakalayci.me/2020/09/10/flashback-data-archive-problems/ I’ve already mentioned about some problems on my second post but these are not kind of problems which will stop your work. The problem I am about talk is that kind of problem. From my
ORA-24244: invalid host or port for access control list (ACL) assignment
Hello everyone, So you wanted to migrate your ACLs to another database or you are trying to add a new acl entity but you got ORA-24244. There are many reasons for that error unfortunately. I wish Oracle provides us more detail about what is the error but I wanted to share what I have seen
export import ACL & ORA-24244 error during import
Hello everyone, it’s been a while since my last post. So, I wanted to write about export and import ACL privileges. They always become a pain (at least for me). after 12c, Oracle introduce us a new and easy way of ACL copying from db to db. export&import. so here is the basic command on