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Observations About the Scalability of Data Loads in ADWC

26 July 2018 Written by Christian Antognini

In the last days, I am running a number of tests based on the TPC-DS benchmark against Oracle’s Autonomous Data Warehouse Cloud service (ADWC). One of the first thing I did is of course to create the TPC-DS schema and populate it. The aim of this blog post is to share some observations related to […]

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Which Privileges Are Required to Use the ADWC Service Console?

17 July 2018 Written by Christian Antognini

The Autonomous Data Warehouse Cloud (ADWC) service provides a Service Console that can be used to monitor the service activity and to carry out a small number of administration tasks (e.g. changing some resource management rules). The documentation specifically says to use the ADMIN user to login. But, actually, any unlocked database user having the […]

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DBMS_CLOUD Package – A Reference Guide

12 July 2018 Written by Christian Antognini

The Appendix A of the Using Oracle Autonomous Data Warehouse Cloud guide describes the DBMS_CLOUD package. Unfortunately, it documents only a subset of the subroutines. And, for some of them, the description could also be enhanced. Therefore, while I was testing all the subroutines the DBMS_CLOUD package provides, I took a number of notes. By […]

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The APPROX_MEDIAN Function – A Test Case

30 October 2017 Written by Christian Antognini

The aim of this post is not to explain how the APPROX_MEDIAN function works (you find basic information in the documentation) but to show you the results of a test case I ran to assess how well it works. Here’s what I did… I started in the Oracle Database Public Cloud an instance of version […]

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Approximate Aggregate Transformation (AAT)

2 November 2016 Written by Christian Antognini

There are situations where approximate results are superior than exact results. Typically, this is the case when two conditions are met. First, when the time and/or resources needed to produce exact results are much higher than for approximate results. Second, when approximate results are good enough. Approximate results are for example superior in case of […]

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Adaptive Query Optimization Configuration: Parameters, Preferences and Fix Controls

7 October 2016 Written by Christian Antognini

The aim of this post is to summarize the knowledge about the 12.1 and 12.2 adaptive query optimizer configuration that, as far as I know, is spread over a number of (too many) different sources. First of all, let’s shortly review which adaptive query optimization features exist: Adaptive plans, which are only available in Enterprise […]

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SQL Trace in Oracle Database Exadata Express Cloud Service

25 September 2016 Written by Christian Antognini

Today I started having a look to the Oracle Database Exadata Express Cloud Service announced last week at Oracle OpenWorld. Note that since the amount of resources provided (in summary, 1 OCPU, 20 or 50 GB of database storage) is very limited, in general, in my opinion that service will only be useful for functional […]

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