Jonathan Lewis Index Costing Threat In the previous post I described a problem with the strategy that the optimizer uses for costing an index fast... 24 January 2017 9 min read
Oracle Aman Sharma in Oracle Understanding SQL Query Parsing – Part 3: Bind Variables and Cursor Sharing In the first and the second parts of this series, we learned what query parsing is, how hard and soft... 20 January 2017 10 min read
Jonathan Lewis Problems with Indexes In my book “Cost Based Oracle – Fundamentals” (Apress 2005) I described a problem with the cost calculation for the... 20 January 2017 7 min read
Houri Oracle Data Type Implicit Conversion Hierarchy In Oracle, under certain circumstances, an implicit data type conversion precludes the use of indexes. Perhaps you have a vague... 09 January 2017 10 min read
Jonathan Lewis Investigating Indexes – 2 In an earlier article on investigating indexes I described some methods for looking at the internal structure of an index... 09 January 2017 16 min read
Zafar Ali Invisible Columns In Oracle Database 12C In Oracle Database 12c, you can set a column in table as invisible either during CREATE TABLE or modifying existing... 12 December 2016 5 min read
Aman Sharma Understanding SQL Query Parsing – Part 2: Parent and Child Cursors In the first article of this series, we learned what query parsing is and what impact it has on query... 12 December 2016 10 min read
Anju Garg Re-registering Databases In A Cluster With srvctl: Problems and Solutions Recently I wanted to create a policy managed database in my 12.1.0.2 flex cluster setup, but free servers are not... 30 November 2016 8 min read
David Njoku JSON For Absolute Beginners: Part 5 – Generating JSON in Oracle In this fifth article in our series on JSON and the Oracle database we’ll be pulling the curtains back on... 11 October 2016 7 min read
Jonathan Lewis Hacking Indexes Indexes are expensive to maintain so we want to get the greatest benefit we can from them and make sure... 03 October 2016 14 min read
David Njoku JSON For Absolute Beginners: Part 4 – Retrieving JSON in Oracle There’s a possibility you’ve parachuted into this series on JSON and Oracle at this point. If you are already familiar... 03 October 2016 11 min read
Anju Garg Migrate Oracle Database To ASM Using ASMCMD Introduction Oracle Database 10g Release 1 introduced Automatic Storage Management (ASM), a new framework for managing Oracle database files. ASM... 29 September 2016 9 min read
Jonathan Lewis Investigating Indexes Rebuilding indexes is an activity that you shouldn’t need to do often. There are always a few special cases –... 28 September 2016 16 min read
Anju Garg Oracle Database 12.1.0.2c: Hot Cloning Of Pluggable Databases Cloning of a Pluggable Database (PDB) in Oracle Multitenant is a great feature and is very useful. Oracle Database 12c Release 1 has... 20 September 2016 8 min read
David Njoku JSON For Absolute Beginners: Part 3 – Storing JSON in Oracle Welcome to part three in this series of articles about Oracle and its uneasy romance with JSON. Uneasy? Well, that’s... 16 September 2016 7 min read
Anju Garg Oracle Database 12.1.0.2c : Hot Cloning of Non-Container Databases In the initial release of Oracle 12c (12.1.0.1c), a non-Container Database (non-CDB) could be converted to a pluggable database (PDB)... 05 September 2016 7 min read
Jonathan Lewis Text Indexes The Oracle database has many features that are not spoken of frequently and a recent note by Connor McDonald reminded... 05 September 2016 14 min read
Aman Sharma Understanding SQL Query Parsing – Part 1 Introduction When it comes to tuning a badly-performing query, there are many things that need to be checked. There may... 05 September 2016 14 min read
Jonathan Lewis Massive Deletes – Part 4 In the previous installment of this series I produced some figures highlighting the main differences between doing a large delete... 05 September 2016 10 min read
David Njoku JSON For Absolute Beginners: Part 2 – Why Use Oracle? In this short series of articles, we’ll be talking about JSON and its integration with the Oracle database. The first... 02 September 2016 5 min read
