Alok Giri Oracle

Migrating Oracle databases can be a complex process, especially when aiming to minimize downtime and data loss. Here are some tricks and techniques to facilitate a smoother Oracle database migration: 1. Pre-Migration Planning and Assessment Thorough Assessment : Conduct a thorough assessment of the source and target environments, including database versions, configurations, schemas, and data size. Compatibility Check : Ensure compatibility between source and target Oracle database versions. Use Oracle's Database Pre-Upgrade Information Tool ( dbupgdiag.sql ) to identify potential issues. Licensing Considerations : Verify licensing requirements and compliance on the target environment. 2. Choosing the Right Migration Method Oracle Data Pump : Best for one-time migrations with minimal downtime. Use parallelism ( PARALLEL ) to speed up data export and import. Oracle GoldenGate : Ideal for zero or near-zero downtime migrations. It allows real-time replication between the source and tar

Setting up Oracle Data Guard on Oracle Cloud Infrastructure (OCI) involves several steps to ensure data protection and disaster recovery for Oracle databases. Below is a high-level overview of the process: 1. Prerequisites and Preparation Oracle Database Versions : Ensure that both the primary and standby databases are running supported Oracle Database versions. OCI Setup : You need an OCI tenancy with necessary permissions, VCNs (Virtual Cloud Networks), and subnets configured. Networking : Ensure the network configuration allows communication between the primary and standby instances. Access : SSH access to the database servers and Oracle Cloud Console access are required. 2. Prepare the Primary Database Configure Archiving : Enable archive log mode and set up the archive destination. Configure Initialization Parameters : Set necessary initialization parameters like DB_NAME , DB_UNIQUE_NAME , LOG_ARCHIVE_CONFIG , LOG_ARCHIVE_DEST_n , FAL_SERVER , etc. Create a Backup : Take a backup

  Oracle latch management is a critical component of the Oracle Database's concurrency control mechanism. Latches are low-level serialization mechanisms used to protect shared memory structures from simultaneous access by multiple sessions, ensuring data integrity and consistency. They are lightweight, in-memory locks that prevent contention and manage the allocation of resources among different processes. Here's a detailed explanation of Oracle latch management: Key Concepts.. Latches vs. Locks : Latches are designed for short-term protection of shared memory structures and are held for a very short time. They are primarily used to ensure that multiple sessions do not simultaneously modify shared data structures, preventing corruption. Locks are used to manage concurrent access to database objects like tables and rows, and they can be held for a longer duration. Types of Latches : Exclusive Latches : Only one process can hold an exclusive latch at a time, ensuring exclusive

Steps... CREATE TABLE index_log (  owner          VARCHAR2(30),  index_name     VARCHAR2(30),  last_inspected DATE,  leaf_blocks    NUMBER,     target_size    NUMBER,  idx_layout     CLOB); ALTER TABLE index_log ADD CONSTRAINT pk_index_log PRIMARY KEY (owner,index_name); CREATE TABLE index_hist (  owner          VARCHAR2(30),  index_name     VARCHAR2(30),  inspected_date DATE,  leaf_blocks    NUMBER,     target_size    NUMBER,  idx_layout     VARCHAR2(4000)); ALTER TABLE index_hist ADD CONSTRAINT pk_index_hist PRIMARY KEY  (owner,index_name,inspected_date); CREATE OR REPLACE PACKAGE index_util AUTHID CURRENT_USER IS vMinBlks     CONSTANT POSITIVE := 1000; vScaleFactor CONSTANT NUMBER := 0.6; vTargetUse   CONSTANT POSITIVE := 90;  -- equates to pctfree 10  vHistRet     CONSTANT POSITIVE := 10;  -- (#) records to keep in index_hist  procedure inspect_schema (aSchemaName IN VARCHAR2);  procedure inspect_index (aIndexOwner IN VARCHAR2, aIndexName IN VARCHAR2, a

Guys  go with Oracle link for more details of Oracle 18C database new featured in between I will come to you with consolidated details. https://docs.oracle.com/en/database/oracle/oracle-database/18/newft/new-features.html#GUID-04A4834D-848F-44D5-8C34-36237D40F194

Owo..So many features of Oracle 18C and i will share the new features soon. PDB Lockdown Profile Enhancements Refreshable PDB Switchover PDB Snapshot Carousel New Default Location of Oracle Database Password File Read-Only Oracle Home Oracle Data Guard Multi-Instance Redo Apply Supports Use of Block Change Tracking Files for RMAN Backups Automatic Correction of Non-logged Blocks at a Data Guard Standby Database Shadow Lost Write Protection Backups from non-CDBs are usable after migration to CDB Support for PDBs as Shards and Catalogs User-Defined Sharding Method Consistency Levels for Multi-Shard Queries Manual termination of run-away queries Approximate Top-N Query Processing LOB support with IMC, Big Data SQL Copy a PDB in an Oracle Data Guard Environment Online Merging of Partitions and Subpartitions Concurrent SQL Execution with SQL Performance Analyzer Database In-Memory Support for External Tables Memoptimized Rowstore Integration of Active Directory Servic

Installation step by step for Oracle 12C (01) Dowload the sotware from the links. edelivery Oracle Site: Oracle Database 12c Release 1 (12.1.0.1) Software (64-bit) (02) unzip linuxamd64_12c_database_1of2.zip unzip linuxamd64_12c_database_2of2.zip (03) Oracle Installation Prerequisites Automatic Setup # # The following package is currently available on the public Yum. # yum install oracle-validated -y # yum update (04)if Oracle validate package performs than ok otherwsie put thse value in /etc/sysctl.conf file. fs.file-max = 6815744 kernel.sem = 250 32000 100 128 kernel.shmmni = 4096 kernel.shmall = 1073741824 kernel.shmmax = 4398046511104 net.core.rmem_default = 262144 net.core.rmem_max = 4194304 net.core.wmem_default = 262144 net.core.wmem_max = 1048576 fs.aio-max-nr = 1048576 net.ipv4.ip_local_port_range = 9000 65500 and run the /sbin/sysctl -p and modify the /etc/security/limits.conf file by below values. oracle   soft   nofile    1024 oracle   hard   nofile    65536 oracle   soft