After creating local and global partial indexes, the last part of this blog post trilogy shows how partial indexes are used by the optimizer for SQL queries – especially for queries in Data Warehouse environments.
Partial Indexes, introduced with Oracle 12c, are available for local and global indexes. In part 2 of this blog post trilogy, let’s focus on global partial indexes on a partitioned table.
Sometimes it would be useful to create indexes for only some of the partitions of a partitioned table. Oracle 12c supports this possibility with Partial Indexes. This blog post shows how local partial indexes can be created – even on an Oracle 11g database.
Data Vault is getting more and more popular for modeling Data Warehouses. Some of my colleagues asked me for book recommendations about this modeling method. Here a short review (from my personal point of view) of two Data Vault standard books.
Identity columns were introduced in Oracle 12c to automatically create sequence numbers for a column – usually for the primary key. Interesting question: What is the behavior of identity columns if the table is exported and imported using Data Pump?
Dynamic SQL is a wonderful feature with a lot of flexibility. Unfortunately, it is not trivial to see the executed SQL statements. A simple trick helps to test and debug PL/SQL code with Dynamic SQL.
Since Oracle 12c, table statistics are gathered automatically for some bulk operations. This inconspicuous new feature called “Online Statistics Gathering for Bulk Loads” is very practical for ETL jobs in Data Warehouses.