Tag Archive: database

Oracle Database 18c: My preferred new features for DBAs
  • 18
    Apr

Oracle Database 18c: My preferred new features for DBAs

Oracle Databse 18c comes with some cool new features for DBAs. In this article I'll list my preferred ones. Just one note: I think the name "Autonomous Database" is quite misleading, as it means that some of the new features...

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Nested table
  • 2
    Mar

Nested table

In PL SQL exists an efficient and adaptable collection of data: Nested table. Nested table is similar to one dimensional array but with some differences : An array has declare number of element – Nested table not. The size of...

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Setup Oracle 12c Enterprise Manager Express for a PDB
  • 4
    Gen

Setup Oracle 12c Enterprise Manager Express for a PDB

There are many articles on the web explaining how to create, duplicate or plug/unplug a Pluggable Database (PDB) into a Container Database (CDB), e remarkable new feature in Oracle 12c Database. A few of them show how to open and...

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Index Tuning
  • 11
    Dic

Index Tuning

Oracle indexes can be tuned looking to three main characteristics: SELECTIVITY: you can calculate index selectivity using this formula: SELECT DISTINCT_KEYS/NUM_ROWS SELECTIVITY FROM DBA_INDEXES / Values range from 0 to 1, where 1 is the optimal value (UNIQUE indexes and...

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