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You are here		blog.tanelpoder.com Optimizer statistics-driven direct path read decision for full table scans (_direct_read_decision_statistics_driven) \| Tanel Poder Blog
\|	\|	tanelpoder.com Alter session force parallel query doesn't really force anything \| Tanel Poder Blog	1.7 parsecs away Travel
\|	\|	Jonathan Lewis has already written about this behavior from the angle of PARALLEL hints. I'm writing a similar article just because the word FORCE in the ALTER SESSION FORCE PARALLEL QUERY syntax. Force should mean that some behavior would always happen (when possible), right? Let's test: SQL> CREATE TABLE t AS SELECT * FROM dba_objects; Table created. SQL> CREATE INDEX i ON t(owner); Index created. SQL> @gts t Gather Table Statistics for table t... PL/SQL procedure successfully completed. Now let's "force" the parallel query in my session, run the query and check the execution plan: - Linux, Oracle, SQL performance tuning and troubleshooting training & writing.	1.7 parsecs away Travel
\|	\|	tanelpoder.com Manual "before" and "after" snapshot support in Snapper v4 \| Tanel Poder Blog	1.0 parsecs away Travel
\|	\|	Snapper used to require access to DBMS_LOCK, so it could sleep for X seconds between the "before" and "after" performance data snapshots. Now it is possible to get away without using DBMS_LOCK. Instead you will run Snapper twice, once for taking the "before" snapshot, then run your workload and then run Snapper again for taking the "after" snapshot and print the output. So, the usual way of running snapper is this: - Linux, Oracle, SQL performance tuning and troubleshooting training & writing.	1.0 parsecs away Travel
\|	\|	afatkulin.blogspot.com Alex Fatkulin's Blog: 11G adaptive direct path reads - what is the cached/dirty blocks threshold?	1.3 parsecs away Travel
\|	\|	11G's ability to do direct path reads during full table scans without utilizing PQ was covered in a number of places already (see this post ...	1.3 parsecs away Travel
\|	\|	hourim.wordpress.com SQLTXPLAIN under Oracle 12c \| Mohamed Houri's Oracle Notes	13.6 parsecs away Travel
\|		I like very much Tanel Poder snapper and Carlos Sierra SQLTXPLAIN. They represent valuable performance diagnostic tools. Unfortunately I am still waiting to find a customer site where I will be allowed or granted necessary privileges to install and to use them. There are client sites where I have been asked to tune queries without...	13.6 parsecs away Travel