Why Isn’t Oracle Allocating More Parallel Slaves?

You have a statement that somebody, without thinking about resources, requested 96 total parallel processes for. They have now come to you, the DBA and want to know why, they aren’t getting the parallel they have requested: The statement starts out something like this: create table table_too_large_data tablespace mart_data1 compress nologging pctfree 0 parallel 16 …

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Gathering Statistics on Highly Partitioned Tables

method_opt=>’for all columns size 1′ This is the method option for DBMS_STATS.GATHER_TABLE_STATS that is commonly recommended- “Let Oracle look at all the columns and decide what kind of statistics, histograms, etc. need to be gathered on each…” I’ve never been real thrilled about it, especially in a data warehouse or mart environment where we rarely …

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