Tables with Memoptimize for Read (fast lookup) Mustafa, 2022-02-152022-02-15 Hi, I would like to share my initial thoughts about memoptimized for read (fast lookup) tables in this post. fast lookup tables came with 18c and they are here to provide faster access to a table if you are using primary key with a equality condition. this is basically single… Continue Reading
How to Restore Dropped PDB Mustafa, 2022-02-04 Hi, it seems easy, right? Well, not that much but not that hard either. if you drop a pdb in a cdb, you cannot restore it using current database because when you drop the pdb, all information about the pdb is lost. So, what is the solution? you need a… Continue Reading
Hierarchical Blocking Session List Mustafa, 2021-10-19 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… Continue Reading
Enable Unified Audit on Linux and Windows Mustafa, 2021-09-08 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… Continue Reading
Blockchain vs Immutable tables Mustafa, 2021-08-202021-10-26 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… Continue Reading
ORA-00600 [kzan_open_osfile:ksfdread] while querying/purging unified audit Mustafa, 2021-08-08 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: [kzan_open_osfile:ksfdread], [], [], [], [], [], [], [], [], [], [], [] Normally, I… Continue Reading
X Forwarding for an Oracle DBA Mustafa, 2021-08-022021-08-02 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… Continue Reading
Create a Clone DB from Backup on the Same Server (or remote) Mustafa, 2021-04-262021-04-27 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,… Continue Reading
Pragma UDF & Deterministic Mustafa, 2021-04-09 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… Continue Reading