Restore a table / database from full backup – Yet another way

Restore requests are common and so are the restores of specific entities: a database, or one or more table(s). This has been discussed a lot and we have plenty of tools and solutions already available. In this blog post we…

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Oracle Parallel Query Hints – Part 3: PX_JOIN_FILTER

In part one of this series on Oracle Parallel Query Hints, I looked at PQ_DISTRIBUTE, and part two was about PQ_Replicate. Now, for the third part in the series, I will take a look at PX_JOIN>FILTER. The PX_JOIN_FILTER is a…

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Building Data Tests in PowerShell

While working with a client recently, we came across a problem while testing data for completeness or errors after running an ETL process to import & manipulate the data. The main issue we ran across was that the overall client…

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Log Buffer #544: A Carnival of the Vanities for DBAs

This Log Buffer edition covers Cloud, Oracle, and MySQL.

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Oracle Parallel Query Hints. A reference series Part 2: PQ_REPLICATE

In Part 1 of this series, we talked about the basic mechanics of the PQ_DISTRIBUTE hint. I did mention the PQ_REPLICATE, and here are all of the details. Oracle Database 12.2, has added a new feature that allows PQ processes…

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Azure Cloud Shell – Cloud what?

What is Azure’s Cloud Shell? Azure Cloud Shell is a browser-based, interactive shell that comes in two flavors: PowerShell and Bash. Microsoft has had this in public preview for some time now. It offers you the ability to pretty much…

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Debugging CBQT OR Expansion with 10053 trace

I had been working with a client to add a little bit of functionality to an analytical view that we had been running queries against for a while. The functionality was easy to implement but during testing we found that…

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Spark UDF Memoization

Memoization is a powerful technique that allows you to improve performance of repeatable computations. Although it would be a pretty handy feature, there is no memoization or result cache for UDFs in Spark as of today. In fact it’s something…

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Meetings That End With No Questions

Are there any questions? Crickets, absolute silence… Your meeting would have had one person speaking most of the time (you). The themes may have varied, but let us assume that it was about the need to “pull up” or otherwise…

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Spark Scala UDF Primitive Type Bug

I was working on an instrumentation framework for Scala UDFs in Spark when I noticed a subtle difference in the execution plan depending on whether I used wrappers or not. It looked like some code was added or was not…

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