In an effort to simplify the migration process from other RDBMS sources to Oracle databases, Oracle introduced in version 12c a new feature called “Identity Columns”.
Based on a sequence generator, the identity column will be assigned an increasing integer value from this sequence generator. Identity columns are automatically incrementing columns and can be indexed as any other column type.
Introduced in Oracle Database 11g Release 2, file watchers allow triggering jobs when a new file is created in a predefined operating system path. A file watcher can watch for a file on the local system or a remote system. As prerequisite to use file watchers, the database Java virtual machine (JVM) component must be installed.
Video demonstration of deploying 50 Oracle 12c databases using vRealize Automation (formerly vCloud Automation Center) on a Pure Storage All-Flash array in 22 minutes. This demo was presented in two sessions during VMworld 2014 US along with being featured in the Pure Storage booth. It was also presented at the VMware booth in the vCloud Automation Center and Virtualizing Business Critical Applications streams.
With Oracle Database 12.1.0.2, Oracle has released its In-Memory Database functionality. In short, Oracle In-Memory database provides transparent column-format memory access over an existing Oracle database. The normal row-format memory access is preserved for fast OLTP transactions; however, with new system parameters, that same data can be accessed from memory in column-format, drastically improving OLAP performance. Because it is transparent, there is no need to change applications to leverage this new functionality, which had previously only been exposed in engineered systems and ZFS as storage-level optimizations.
This article will be discussing Reverse Binary Tree index feature of Oracle database, an index which is there to solve block contention problem. It will be discussing how it works, what are its advantages and its limitations. When a normal binary tree index based on a numeric column populated by a sequence, it gives rise to hot block problem. Applications trying to insert new rows will face “buffer busy wait”, because everyone wants to write to same block. This problem is called hot block or block contention.
