Ram Perumal

I’m a coffee lover—no other drink gives me as much motivation as a cup of filtered-coffee, day or night. I love data, passionate about data architecture, analytics and optimization. I architect and coach teams to build healthier, scalable and optimally performing data-intensive applications; and help enterprises develop insights that drive action, performance and business growth.

Fast SPLIT PARTITION operation is unusually slow

I recently observed that the total time taken to split an empty partition, in 10.2.0.5, has increased by many fold—i.e. from under 30 seconds to 60 minutes. SPLIT PARTITION operation is, simply, creating two new partitions and redistributing the rows from the partition being split into the two new partitions. Often one new partition contains …

Fast SPLIT PARTITION operation is unusually slow Read More »

Computing Oracle SQL_ID and HASH_VALUE

I needed an hash function, in Java, which is simple, practically less collision and provides a short alphanumeric or an unsigned number as hash for any string or text. I stumbled upon few blog posts that explain how Oracle SQL_ID and HASH_VALUE are calculated by database engine, concisely and elaborately; also implementations in Python and …

Computing Oracle SQL_ID and HASH_VALUE Read More »

Deprecated SQL*Plus Commands in Oracle 11g R2

This just a short note to point out that the below SQL*Plus commands are deprecated as of Oracle 11g R2, but available in the current release of SQL*Plus for backward compatibility. The documentation states that this may only be available by setting the SQLPLUSCOMPATIBILITY variable in the future releases.  You should modify scripts using obsolete …

Deprecated SQL*Plus Commands in Oracle 11g R2 Read More »

Toad 11.0: Deprecated Features

This is just a short note to point out that, as per release notes, the following features have been removed from the menus in Toad 11 and they will be permanently removed after Toad 11. View Extents and Free Space Deficits—These features were created for dictionary-managed tablespaces, which are rarely used since Oracle 8i introduced …

Toad 11.0: Deprecated Features Read More »

Report Memory Map of a Process in Linux

The pmap command can be used to obtain a memory map report for a process or list of processes. In my opinion, it is a great tool to explore memory leaks and any other memory related issues. If you simply invoke pmap with no options, it will list the usage with general available options, as shown …

Report Memory Map of a Process in Linux Read More »

Eliminating “Us And Them”: Making IT and the Business One

Eliminating “Us And Them”: Making IT and the Business One is for anyone who is interested in knowing the divide between IT and business. It is a must read for IT professionals and business persons in your company. This book has 25 chapters, they are: 1.  Us and Them 2. When IT is “Us” and …

Eliminating “Us And Them”: Making IT and the Business One Read More »

RECORD feature of TKPROF

This is just a short note the point out that RECORD option of TKPROF is extremely useful in recording and capturing the non-recursive SQL statements in the order of execution from the SQL trace file.  I have not had a requirement to use it until—today—one of my developers lost the original test script used when …

RECORD feature of TKPROF Read More »

SQL*Plus Feature: TIMING and SET TIMING command

SET TIMING—one of the most frequently used commands—displays timing statistics on each SQL command or PL/SQL block. What if you want to collect timing statistics for multiple group of statements? TIMING command becomes handy in such situation—one of things that I knew and have forgotten over time. It can be used to collect data to do …

SQL*Plus Feature: TIMING and SET TIMING command Read More »

SQL returns wrong result when the table order is swapped

I noticed a strange behavior—a SQL statement, which used to return no rows in the past, started returning rows in an environment where the test data set has not changed. I performed a code comparison and observed a difference in the order of a table in FROM clause. After looking through, I found a bug entry on MOS …

SQL returns wrong result when the table order is swapped Read More »

The Art of Scalability: Scalable Web Architecture, Processes, and Organizations for the Modern Enterprise

The Art of Scalability: Scalable Web Architecture, Processes, and Organizations for the Modern Enterprise—A must read for technical and business persons in your company, if you are looking to scale your business, whether you are a startup or Fortune 500. Scalability is widely used term, often, refers to scaling a specific technology—for most technical people. …

The Art of Scalability: Scalable Web Architecture, Processes, and Organizations for the Modern Enterprise Read More »