2015/08/11

OTN Article: Oracle Database 12c In-Memory (Part I, II - Spanish / Portuguese)

Oracle Technology Network Latina started publish our new article series about Oracle Database In-Memory. This articles is first about In-Memory in OTN Latina articles.

First and Second parts of Oracle Database In-Memory article series published in 2 language (Spanish/Portuguese) same time.

In Spanish Language

Part I: http://www.oracle.com/technetwork/es/articles/database-performance/oracle-database-12c-in-memory-2595521-esa.html
Part II: http://www.oracle.com/technetwork/es/articles/database-performance/oracle-database-in-memory-part2-2595866-esa.html





In Portuguese Language

Part I; http://www.oracle.com/technetwork/pt/articles/database-performance/oracle-database-12c-in-memory-2595527-ptb.html
Part II: http://www.oracle.com/technetwork/pt/articles/database-performance/oracle-database-in-memory-part2-2595874-ptb.html





My special thanks to Joel Perez (Venezuela), Flavio Soares (Brazil) and Sebastián D'Alessandro (Argentina).

Regards
Mahir M. Quluzade

2015/08/04

Oracle Database 12c: Statistics created as the data was loaded

As you know, Oracle Magazine July/Aug 2015 issue released. You can free subscribe to Oracle Magazine digital edition and you can read here or you can read technical  articles here.

I subscribed Oracle Magazine, in current issue have very interesting articles.

One of interesting article of Oracle Expert Tomas Kyte (as known AskTom) with title: On Learning from Mistakes


In this article Tom talks about Cost Based Optimizer and shown how optimizer learning from mistakes. I don't want review this article, but there have about interesting new feature of Oracle Database 12c.   

Tom wrote:

The fact that the NOW column of the query against USER_TABLES is the same as the LAST_ANALYZED column shows that statistics were created as the data was loaded—this is a new feature of Oracle Database 12c. Since Oracle Database 10g, the database has been computing statistics automatically for indexes when you create or rebuild them. With Oracle Database 12c, the database does the same for tables. Further, as you can see in the example in Listing 1, there are basic statistics on the columns in the table as well.

I want share my test environments outputs with you:


[oracle@oel62-ora12c2 Desktop]$ export ORACLE_SID=prmcdb
[oracle@oel62-ora12c2 Desktop]$ sqlplus "/ as sysdba"

SQL*Plus: Release 12.1.0.2.0 Production on Tue Aug 4 17:32:00 2015

Copyright (c) 1982, 2014, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics, Real Application Testing
and Unified Auditing options

SQL> select banner from v$version; 

BANNER
--------------------------------------------------------------------------------
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
PL/SQL Release 12.1.0.2.0 - Production
CORE 12.1.0.2.0 Production
TNS for Linux: Version 12.1.0.2.0 - Production
NLSRTL Version 12.1.0.2.0 - Production