The degree field in Dba_tables is queried from the Sys.tab$.degree field, and the formula is Lpad (Decode (T.degree, 32767, ' DEFAULT ', NVL (t.degree,1)), 10, which is 32767 is default, when the table is not set degree is empty then degree is 1; Oracle parallelism is limited by CPU cores in actual SQL execution, and this parameter parallel_degree_policy defaults to Manul The actual degree of parallelism Cpu_count * PARALLEL_THREADS_PER_CPU
Query table's Degree
Select O.owner,o.object_name,t.degree, Lpad (DECODE (T.degree, 32767, ' DEFAULT ', NVL (T.degree, 1)) from sys.tab$ T, Dba_objects o where t.obj#=o.object_id
and O.object_name= ' CUSTOMERS ';
Set the degree of parallelism for a table to 4
ALTER TABLE TableName parallel 4;
Sets the degree of parallelism for the table to default
ALTER TABLE TableName parallel;
To cancel the degree of parallelism of a table
ALTER TABLE TableName Noparallel;
To help understand, you can view two articles
Http://www.eygle.com/archives/2008/04/parallel_degree_instances.html
https://uhesse.com/2011/10/12/auto-dop-differences-of-parallel_degree_policyautolimited/
To help understand, you can view two articles
Http://www.eygle.com/archives/2008/04/parallel_degree_instances.html
https://uhesse.com/2011/10/12/auto-dop-differences-of-parallel_degree_policyautolimited/