Category Archives: Uncategorized

DBMS_METADATA in utilities manual

Just found out that all the good documentation for the DBMS_METADATA package is in the Utilities manual.  I’ve just been looking at the “PL/SQL Packages and Types Reference” manual for the details of how to use DBMS_METADATA.  I’ve been handcuffing … Continue reading

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A day in the life of an Oracle DBA

I thought I would do a fun “day in the life” blog post about the work I’m doing today.  And then chaos ensues! 8:22 AM MST  After starting this blog post and reading my email I updated my time card … Continue reading

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SQLT Data Explosion

Well, I’ve been running SQLT all day.  I’ve got a case open with Oracle support on the issue described in my previous post.  Oracle support wants me to use SQLT to run one of the queries with the long parse … Continue reading

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You got to love Exadata and subpartitioned tables.  We have these queries on one particular table that are taking forever to parse.  Sometimes a simple explain plan on the simplest possible query against the table takes 20 or 30 seconds.  … Continue reading

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Delphix, direct I/O, and direct path reads

I’ve been working on testing performance on a database that uses Delphix as its storage system and ran across an unexpected side effect of using Delphix to clone a production database for testing.  Because Delphix uses NFS to present the … Continue reading

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How to break a large query into many small ones

I haven’t figured out the best way to do this yet so this is a work in progress.  I’m trying to document the process of taking a large query that joins many tables together and breaking it into a series … Continue reading

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Outline hint for query tuning

I had a situation today where I had two slightly different queries that I thought should have the same plan but they didn’t.  So, I needed a way to force the slower query to run with the same plan as … Continue reading

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Yet another test_select package update

Most recent version here(updated). Added these two: display_results(test_name,compared_to_test_name) – output results of testings in the two scenarios.  List results from all queries that ran more than 3 times as long with one test or the other.  Also summarize results with … Continue reading

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Update to test_select package

Quick update to package from previous post. Here is the zip of the download: zip(updated) I added these procs to collect select statements on a source production database and to copy them back (as clobs) to the test database: collect_select_statements(max_number_selects, … Continue reading

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Package to test large select statements

I’ve uploaded this package(updated) that I’m using to test some large select statements.  See the file packagedescriptionv1.txt for a description of the package.  Also, test.sql and test.log is an example of using the package. This is an updated version of … Continue reading

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