Before you read on, please check out my related post on "Function Result Cache". You may find it valuable in this context. Conversation sounds familiar? I am sure you have been privy to a conversation like this between an IT manager and a DBA: Manager: My query is extremely slow. Can you make the query … Continue reading Oracle – Fastest Way To Execute SQL Is? To, Not Execute It! – Query Result Cache – Part II
Why is the APPEND hint so great? In a prior post, we extolled the virtues of the APPEND hint (AKA Direct Path Insert). It is a great option to use • UNDO usage is negligible. It is only generated for index maintenance and meta data changes. The keyword is index maintenance – indexes generate UNDO. … Continue reading Oracle – Is my APPEND Hint Being Ignored? How To Find Out?
Why DELETE is bad? In Oracle, when it comes to deleting ** A L L ** the data from a table (clearing the contents of a staging table for example), using a DELETE statement is the most inefficient choice. Here are some reasons why DELETE is bad It uses UNDO It uses REDO It fires … Continue reading Oracle – TRUNCATE vs DELETE – Spoiler: TRUNCATE Wins & Why? Hours vs Seconds!
Oracle's logical storage structures: To developers who work with Oracle, the concept of tablespace is familiar. We create tables and indexes in tablespaces taking appropriate care not to place all of our data into one tablespace. Let us take a quick look at the logical structure of an Oracle database A database has one or … Continue reading Oracle’s APPEND Hint – The Key Secret To Fast BULK Loading With NOLOGGING!