Oraclezine

MANAGING SEMANTIC DATA MODELS IN ORACLE DATABASE

2011-07-06T13:43:00.000-07:00

Oracle Database 11g incorporates native RDF/RDFS/OWL support, enabling application developers to benefit from a scalable, secure, integrated, efficient platform for semantic data management. This semantic database support is part of Oracle Spatial 11g, an option to Oracle Database. Application developers can add meaning to data and metadata by defining a set of terms and the relationships between

BEWARE: Oracle 11g New Feature Causes AMM to Restart

2011-03-16T17:36:00.001-07:00

Beware, following upgrades to 11gR2, you can find that AMM has reappeared, even if you think that you have disabled it. Oracle Automatic Memory Management (AMM) was introduced in Oracle 10g for small databases where a one-sized-fits-all approach was used in small “hands-off” databases that did not have a DBA to intelligently allocate the SGA pools. When a small system has a too small RAM

Tightly Packing Table Rows onto Data Blocks

2011-01-28T19:43:00.000-08:00

What do you do when you have some read-only tables, meaning there will be no UPDATEs, INSERTs or DELETEs and you want to pack the rows onto the data blocks as tightly as possible? The goal is to minimize wasted space while still insuring fast data retrieval through the use of an index. There following is a list of several factors that govern free space within a table and a tablespace: *

Oracle SYSDBA Privilege

2011-01-03T21:24:00.001-08:00

What can the SYSDBA privilege do? SYSDBA is like a role in the sense that it is granted, but SYSDBA is a special built-in privilege to allow the DBA full control over the database such as: * Access to all data dictionary tables (dba views) * Access to all v$ views and x$ structures * Perform startup/shutdown commands * alter database: mount, open, back up, or change character set

Oracle DBA’s Draw False Conclusions

2011-01-03T21:20:00.001-08:00

There is a disturbing trend in Oracle whereby beginner DBAs are tempted to take a single "test case", and over generalize it, drawing false conclusions and inferring causation where none exists. Instead of a full-blown benchmark using real SQL workloads, some DBAs misunderstand basic science and suggest that a single "test case" can be used to infer causation and explain how Oracle behaves

Oracle SCAN for RAC

2011-01-03T21:17:00.001-08:00

Will the new Oracle 11g R2 RAC feature Single Client Access Name (SCAN) replace Transparent Application Failover (TAF) in a RAC cluster? If so, should I use SCAN instead of manual load balancing? According to reliable sources on the web, SCAN provides a single domain name via DNS, allowing end-users to address a RAC cluster as if it were a single IP address. SCAN works by replacing a

Database Administrator - Top Ten Jobs in USA

2011-01-03T20:48:00.001-08:00

Top Ten Best Jobs in the USA Want one of the top 10 of the 100 best jobs in the United States? According to research conducted by CNNMoney.com and compensation experts PayScale.com, it's a good time to consider becoming a Database Administrator! Their criteria for the best jobs in the USA include: * great compensation * satisfying work * growth opportunities Their research was

Oracle Cardinality Feedback Secrets

2010-09-23T19:32:00.003-07:00

What is Oracle cardinality feedback? I hear that cardinality feedback is new in 11g and helps Oracle make better optimizer decisions. Is cardinality feedback shared to other SQL statements? Is cardinality feedback stored between database bounces? If so, where is the cardinality feedback stored? The expert responds: Answer: Like all new features, cardinality feedback is not well

Secret Internals of Temporary Tables

2010-09-21T19:06:00.000-07:00

While tools like Oracle analytics are great for solving complex problems using only SQL, the cryptic syntax and funky performance are less than ideal for production shops where maintainability and fast performance are primary goals. Oracle has the Global Temporary table (GTT) and the SQL-99 WITH clause to allow us to decompose a large and complex query into its components. This divide and

Tips for Hiring Production Support DBA

2010-09-21T19:04:00.000-07:00

Oracle employers are going to great expense to ensure that their new Oracle DBAs will not pose a risk to their mission-critical data. The stakes are high, and the new is full of reports of companies that have lost millions of dollars due to the immoral behavior of database professionals. * - In Florida, William Sullivan faces accusations that he stole millions of records from the database,

Tuning Temporary Tables and WITH Clause Materializations

2010-09-15T23:09:00.000-07:00

Question: I have a performance tuning problem with global temporary tables (GTT) and the WITH clauses in a busy vendor application. Once created, I cannot see the temporary table rows for a specific user session and I cannot see how to manipulate the SQL against the temporary tables to force my best explain plan. What are the ways to index, monitor and tune global temporary tables? The

Oracle ASSM Performance

2010-09-12T21:02:00.000-07:00

Tuning DML With ASSM Bitmap Freelists The Oracle community has mixed feelings about using ASSM tablespaces. The savvy DBA has to recognize the tradeoff between one-size-fits-all convenience and the power of setting individual object parameters for tables and indexes. The following page has more information on ASSM internals: http://oracle-tips.c.topica.com/maaoemgabZ7xVbMnSnCb/

RAC Node Affinity with Parallel Instance Groups

2010-09-02T19:52:00.000-07:00

Question: I want to load balance my RAC system, and I was considering using node affinity approach. I also understand that RAC has a parallel instance groups feature for RAC balancing. What are the advantages of each approach? Answer: There are several approaches to partitioning a RAC cluster with the most popular being functional load balancing, which involves dedicating like-minded

What is CPU affinity and how can it help with my Oracle system?

2010-08-27T21:11:00.001-07:00

Question: I have a 32 CPU Linux server with four large applications, and I want to dedicate 4 banks of 8 CPUs to each application. Is CPU affinity a good practice for Oracle? So, what do the experts say? Answer: Processor (CPU) dedication is called CPU affinity, and it has been used for decades on large mainframe computers. Today, CPU affinity a common technique on large Oracle servers

Setting the Priority for Oracle Batch Jobs

2010-08-27T20:05:00.000-07:00

Question: What is the mechanism to set priority for batch jobs? I want my stored procedures to have lower priority than the real time processes. We want the batch job access wait, while the application processes get a higher dispatching priority. The batch jobs are submitted via dbms_scheduler, and I want them to have less priority after they are submitted. The expert says: Answer: When

The Oracle Two Phase Commit

2010-07-14T22:41:00.000-07:00

What is an Oracle two phase commit? Oracle developed the two phase commit to allow for the controlling SQL to ensure that all remote sites have committed their data before issuing a local commit. While data integrity is managed very effectively within a single database with row locking, deadlock detection and roll-back features, distributed data integrity is far more complex. Recovery in

Oracle 1Z0-054 Exam - Free 1Z0-054 Sample Questions:

2010-05-25T00:11:00.000-07:00

1. After running SQL Performance Analyzer (SPA), you observe a few regressed SQL statements in the SPA output. Identify the two actions that you would suggest for these regressed SQL statements. (Choose two.) A. Running SQL Access Advisor B. Adding them to SQL Plan Baseline C. Submitting them to SQL Tuning Advisor D. Running Automatic

Tips for Taking the OCP Exam

2010-05-21T23:06:00.000-07:00

The following tips will help you prepare for and pass each exam: Each OCP test contains about 60–80 questions to be completed in about 90 minutes. Answer the questions that you know first, so that you do not run out of time. Many questions on the exam have answer choices that at first glance look identical. Read the questions carefully. Don’t just jump to conclusions. Make sure that you

Skills Required for DBA Certification

2010-05-21T23:05:00.000-07:00

Listed here are some of the skills you must master for DBA certification. Even if you do not have all the skills, you can start taking the exams for which you feel confident. The exams can be taken in any order. Understanding RDBMS concepts Writing queries and manipulating data Creating and managing users and database objects Knowledge of PL/SQL programming and constructs Oracle

Oracle Application Developer - Oracle Certifications

2010-05-21T23:04:00.000-07:00

This track tests your skills in client-server application development using Oracle application development tools, such as Developer/2000, SQL, PL/SQL, and SQL*Plus. The following five tests comprise this track: 1Z0-001: Introduction to Oracle: SQL and PL/SQL 1Z0-101: Develop PL/SQL Program Units 1Z0-121: Developer/2000: Build Forms I 1Z0-122: Developer/2000: Build Forms II 1Z0-123:

Database Administrator (DBA) - Oracle Certifications

2010-05-21T23:03:00.000-07:00

The role of the Database Administrator (DBA) has become a key to suc- cess in today’s highly complex database systems. The best DBAs work behind the scenes but are in the spotlight when critical issues arise. They plan, create, maintain, and ensure that the database is available for the business. They are always watching the database for performance issues and to prevent unscheduled downtime.

Why Become an Oracle Certified Professional?

2010-05-21T23:01:00.000-07:00

T he number one reason to become an Oracle Certified Professional is to gain more visibility and greater access to the industry’s most challenging opportunities. The OCP program is the best way to demonstrate your knowledge and skills in Oracle database systems. The certification tests are scenario-based, which is the most effective way to assess your hands-on expertise and critical

Conducting a Database Administrator Background Check

2010-04-24T06:27:00.000-07:00

The job of Database Administrator (DBA) is a mission-critical job whereby a corporation entrusts billions of dollars worth of data to a single individual. Database Administrators are generally paid at the same level as a mid-level manager or Vice President, and it is not uncommon to find people with salaries in excess of $150,000 per year, even more for special DBAs who have functional and

2010 Top Computer Information Systems Jobs

2010-04-14T23:02:00.001-07:00

Oracle jobs are back, and the Oracle Corporation 2010 salary survey shows the average DBA salary at $97,000.00 per year. As a general guideline, a well-qualified Oracle professional with a master's degree will earn their age times three, so a 30 year old Oracle professional can expect, on average, at least $90,000.00 per year.Many Oracle-related jobs also made the CNN Money 2010 survey on

Oracle RAC Best Practices

2010-04-07T23:47:00.000-07:00

Information Systems are more demanding than ever. End users demand instantaneous response time, day or night, and Oracle Corporation continues to be challenged to help provide continuous availability for their database products. One high availability tool is Oracle’s Real Application Clusters (RAC). RAC has been used for more than a decade (via its predecessor, Oracle Parallel Server) to