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Declarative PL/SQL

 SQL is a set-oriented, language. A language or statement is declarative if it describes the computation to be performed (or in SQL, the set of data to be retrieved/modified) without specifying how to compute it. PL/SQL is a , tightly integrated with SQL, and intended primarily to allow us to build powerful, secure APIs to underlying data (via SQL). If I try hard, I can maximize the procedural side of PL/SQL and minimize the declarative aspect of SQL (primarily by ignoring or discounting the set-orientation of SQL). That's generally a bad idea. Instead, we Oracle Database developers make the most of the many powerful features of SQL (think: analytic functions, pattern matching, joins, etc.), and minimize processing in PL/SQL.Know more sql plsql online training What we should also do, though, is recognize the make the most of the declarative features of PL/SQL. There are two big reasons to do this: 1. When you don't tell the PL/SQL compiler how to do things, the optimizer has
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What is RAC(Real Application Cluster)

  RAC  stands for  Real Application Clusters . It’s a high availability solution for  Oracle DB . Here two or more nodes (instances) are clustered as a single DB by using shared disks. So there’s no single point of failure from the DB side. A cluster comprises different interconnected computers or servers that show up as in case they are one server to conclusion clients and applications. Oracle RAC empowers you to cluster Oracle databases. Oracle RAC employments Oracle Clusterware for the foundation to tie numerous servers so they work as a single system. Oracle Clusterware may be a convenient cluster administration arrangement that coordinates with Oracle Database. Oracle Clusterware is additionally a required component for utilizing Oracle RAC. In expansion, Oracle Clusterware empowers both single-instance Oracle databases and Oracle RAC databases to utilize the Oracle high-availability foundation. Oracle Clusterware empowers you to make a clustered pool of capacity to be utilized by
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Oracle RAC Interview Questions & Answers

  1. Where are the Clusterware files stored on a RAC environment? The Clusterware is installed on each node (on an Oracle Home) and on the shared disks (the voting disks and the CSR file) 2. Where are the database software files stored on a RAC environment? The base software is installed on each node of the cluster and the database storage on the shared disks. 3. What kind of storage we can use for the shared Clusterware files? - OCFS (Release 1 or 2) - raw devices - third party cluster file system such as GPFS or Veritas 4. What kind of storage we can use for the RAC database storage? - OCFS (Release 1 or 2) - ASM - raw devices - third party cluster file system such as GPFS or Veritas 5. What is a CFS? A cluster File System (CFS) is a file system that may be accessed (read and write) by all members in a cluster at the same time. This implies that all members of a cluster know more oracle rac training have the same view. 6. What is an OCFS2? The OCFS2 is the Oracle (version 2) Cluste
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