With PostgreSQL 15 version, logical replication became applicable by filtering on the tables by column and row. In this way, replication can be made in the desired columns and rows in the tables. Logical Replication wal_level=logical For logical replication, the wal_level parameter must be logical in the postgresql.conf file . By default, the value of wal_level is replica . The replica value provides the necessary wal files for streaming…
Category: Databases
PostgreSQL 15 New Features
PostgreSQL version 15 was released and made available on October 13, 2022. PostgreSQL, the most advanced open source database, brought many new features with its 15th version. PostgreSQL 15 New Features Merge Command With the release of PostgreSQL 15, the Merge command was also made available. MERGE allows you to write a conditional SQL query that…
Single Instance Oracle 19c Database and Grid Infrastructure 19.11 Release Update
Firstly, OPatch directory has to be actual. You can download actual OPatch files from https://updates.oracle.com/download/6880880.html according to you database and operating system version. OPatch directory is in the grid home and oracle home directory. You have to change it with actual OPatch files. You can backup orjinal OPatch files before changing. Check Current Patches My…
How to Use pg_rewind in PostgreSQL 12
pg_rewind is a PostgreSQL tool since 9.5 version. It provides synchronization between standby and old primary. Especially, pg_rewind provides advantage for big databases. You can sync databases without using pg_basebackup. pg_rewind scans the old primary database’s pgdata folder and identifies data blocks changed during the switch to standby database, then copies only changed blocks from…
PostgreSQL 12 Streaming Replication Installation and Failover Operations on CentOS 7
PostgreSQL has few feature for standby technology. I generally use streaming replication. This is very easy and confident. Streaming replication use a replication user for replication operations.Streaming replication allows a standby server to stay more up-to-date than is possible with file-based log shipping. The standby connects to the primary, which streams WAL records to the…
Oracle 19c R3 Active Data Guard Installation on Oracle Linux 7.7
Oracle Data Guard ensures high availability, data protection, and disaster recovery for enterprise data. Oracle Data Guard provides a comprehensive set of services that create, maintain, manage, and monitor one or more standby databases to enable production Oracle databases to survive disasters and data corruptions. Oracle Data Guard maintains these standby databases as copies of…
Oracle 19c R3 Real Application Clusters (RAC) Installation Steps on Oracle Linux 7.7
Oracle Real Application Clusters (RAC) provides high availability (HA) and scalability to the Oracle Database without requiring any application changes. Oracle RAC allows multiple instances running on different servers to access the same physical database stored on shared storage. Database spans multiple hardware systems and yet appears as a single unified database to the application….
ORA-01078 failure in processing system parameters LRM-00108 could not open parameter file Oracle RAC
Problem ORA-01078: failure in processing system parameters LRM-00109: could not open parameter file ‘//dbs/init.ora’ Solution cd $GRID_HOME/bin chmod 6751 oracle
Turkish Characters Order By Sort Problem in Oracle
Using order by in column that contains special Turkish characters like ç,ğ,ö,ş,ü can be problem. All special Turkish characters can be listed at the end of the list. You can resolve this problem with NLSSORT. select * from tablename order by NLSSORT(columnname,’NLS_SORT=TURKISH’)
Reset MySQL Root User Password in Centos 7
Stop MySQL Database systemctl stop mysqld.service Start MySQL as Safe Mode mysqld_safe –skip-grant-tables & Connect MySQL Database With Root User mysql -uroot Change Root Password use mysql; update user set password=PASSWORD(“newpassword”) where user=’root’; flush privileges; exit Restart MySQL Database systemctl stop mysqld.service systemctl start mysqld.service Connect MySQL Database With Root User With New Password mysql…