Sadan's Oracle dba Blog

  Oracle OEM Holistic Patch  The Concept Starting with Oracle Enterprise Manager (OEM) 13.5 RU24 (October 2024), Oracle introduced the Holistic Patch for OEM — a unified patching model that consolidates several separate updates into a single coordinated package. Previously, administrators had to patch: * The OMS and Agents with the quarterly Release Update (RU). * OEM Application via the System Patch Bundle (SPB). * WebLogic CPU and JDK manually. There was an element of complication because of the need to keep the solution homogeneous. With the Holistic Patch, the last two steps are merged into a single patch bundle. Now we have a new Holistic patch for OEM that is released with each new OMS Release Update. Prerequisites Apply RU 24 Patch  PATCH 36761595  /later on all OMSes before applying Oct Holistic Patch   PATCH 37305292             (OR) Apply RU 25 Patch  PATCH 37057635  /later on all OMSes before applying ...

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  REPLICATION 1.replication prerequisites: 1. Verify connectivity between publisher, distributor and subscriber. Ifyou are unable to access then have your network team to open firewall ruleso that these servers can communicate. 2. You need to be sysadmin in order to setup replication. 3. Primary Key for each table. That should be fine anyway as it alreadyhas replication setup. 4. Allocate enough space for Transaction log 5. Do not use explicit transactions in trigger at the subscriber if you currently have because that can raise error sometimes. 2. Replication Agents Behaviour? Replication Agents The following are the replication agents and let us discuss each one of those in detail. *  Snapshot Agent  – It is used for creating and propagating the snapshots used in snapshot replication. Each Published database has its own Snapshot Agent that runs on the distributor and connects to the publisher and takes a snapshot of the objects. It then updates the information in the di...

AlwaysOn Availability Groups - FAQ     1. Which SQL Server Editions include AlwaysOn Availability Group functionality?     SQL Server Enterprise Edition   2. Do I need to use a specific Windows Server edition with AlwaysOn Availability        Groups?     You need to use Windows Server Enterprise above         3. What are the prerequisites for AlwaysOn Availability Groups? More information can be found here  http://msdn.microsoft.com/en-us/library/ff878487.aspx   4. How many replicas can I have in an AlwaysOn Availability Group? 5 total – 1 primary and up to 4 secondaries   5. How many databases can participate in an AlwaysOn Availability Group? Up to 100 is the recommendation, but it’s not enforced   6. How many AlwaysOn Availability Groups can I have on an instance? Up to 10 availability groups is the recommen...

After installing OLE 7.9, install below things at OS level , then create Oracle Database 19c and Apply 19.26 or later patch.  .. [oracle@oemrepo soft]$ /u01/app/oracle/product/19.3.0/dbhome_1/OPatch/opatch version OPatch Version: 12.2.0.1.49 OPatch succeeded. [oracle@oemrepo soft]$ [oracle@oemrepo soft]$ [oracle@oemrepo soft]$ [oracle@oemrepo soft]$ ps -ef|grep smon oracle    3750     1  0 13:13 ?        00:00:00 ora_smon_orcl oracle    5258  4890  0 13:27 pts/1    00:00:00 grep --color=auto smon [oracle@oemrepo soft]$ . oraenv ORACLE_SID = [oracle] ? orcl The Oracle base has been set to /u01/app/oboseracle [oracle@oemrepo soft]$ sqlplus / as sysdba SQL*Plus: Release 19.0.0.0.0 - Production on Sat Feb 7 13:27:32 2026 Version 19.3.0.0.0 Copyright (c) 1982, 2019, Oracle.  All rights reserved. Connected to: Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production Version 19.3.0.0.0 SQL...