Author Archives: Bobby

About Bobby

I live in Chandler, Arizona with my wife and three daughters. I work for US Foods, the second largest food distribution company in the United States. I have worked in the Information Technology field since 1989. I have a passion for Oracle database performance tuning because I enjoy challenging technical problems that require an understanding of computer science. I enjoy communicating with people about my work.

Pushed out new version of PythonDBAGraphs

I pushed out a new version of PythonDBAGraphs. I got a new laptop at work so I am setting it up with the software that I need to do my job. I decided that instead of reinstalling Enthought Canopy I would go … Continue reading

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X86-64 Assembly Book

I have written earlier blog posts about my diversion from studying Oracle to studying computer science. Here are some relevant posts: url1,url2,url3,url4. After finishing the math for computer science online class and book that I was working on I stared working … Continue reading

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Finished reading the Snowflake database documentation

I just finished reading the Snowflake database documentation and I thought I would blog about my impressions. I have not spent a lot of time using Snowflake so I can not draw from experience with the product. But, I read all … Continue reading

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Submitted two abstracts for Oracle OpenWorld 2017

I submitted two abstracts for Oracle OpenWorld 2017. I have two talks that I have thought of putting together: Python for the Oracle DBA Toastmasters for the Oracle DBA I want to do these talks because they describe two things that I … Continue reading

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How to find the object that caused ORA-08103 error

A developer told me that two package executions died with ORA-08103 errors and he didn’t know which object caused the errors. I found two trace files that had the following contents: *** SESSION ID:(865.1201) 2017-04-17 10:17:09.476 OBJD MISMATCH typ=6, seg.obj=21058339, diskobj=21058934, … Continue reading

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Optimizer bug fix makes a query run more than 3 times slower

I’m working on an 11.1.0.7 to 11.2.0.4 upgrade and found a handful of queries that run more than 3 times longer on 11.2.0.4 than 11.1.0.7. The data and optimizer statistics are very similar on the two test databases. I’m pretty … Continue reading

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_small_table_threshold=1000000 results in > 5x query speedup

Today I sped a query up by over 5 times by setting _small_table_threshold=1000000. Here is the query elapsed time and a piece of the plan showing its behavior before setting the parameter: Elapsed: 00:28:41.67 —————————————————————————————————————————————————————————- | Id | Operation | Name … Continue reading

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Jetpack 4.8 outage

I just got my bobbydurrettdba.com blog back online. It seems that an automatic update of Jetpack to version 4.8 took it down last night. I thought I would post a quick comment on how I resolved it because it is … Continue reading

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Information Technology Jobs Posted

My company, US Foods, has posted a number of information technology jobs that are in Chicago (Rosemont)  or Phoenix (Tempe). Here is the web site: https://www.usfoods.com/careers.html IT jobs are under the “Technical” category. Bobby

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Using Delphix to support Oracle upgrade

I’m working on upgrading a very buggy unpatched 11.1.0.7 Oracle database to a fully patched 11.2.0.4 version. I’m using Delphix to support the upgrade and it has been a big help so far. This is on the HP-UX 11.31 Itanium platform. … Continue reading

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