Create CTXCAT index in parallel mode

I am using Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production with oracle text version 11.2.0.2.0.
Following script is used to create the ctxcat index but I noticed it is not creating the index in parallel. We have 16 cpu server. The table onto which text index is created has no partition.
BEGIN
--Storage preference
Ctx_Ddl.Create_Preference ('IDX_STORE', 'basic_storage');
Ctx_Ddl.Set_Attribute (preference_name => 'IDX_STORE',
attribute_name => 'I_TABLE_CLAUSE',
attribute_value => 'TABLESPACE C_DATA_02');
Ctx_Ddl.set_attribute ('IDX_STORE',
'I_INDEX_CLAUSE',
'TABLESPACE C_IDX_02 COMPRESS 2');
Ctx_Ddl.set_attribute (
'IDX_STORE',
'R_TABLE_CLAUSE',
'TABLESPACE C_DATA_02 LOB(DATA) STORE AS (CACHE)'
--Wordlist
ctx_ddl.create_preference ('nbcwordlist', 'BASIC_WORDLIST');
ctx_ddl.set_attribute ('nbcwordlist', 'PREFIX_INDEX', 'TRUE');
ctx_ddl.set_attribute ('nbcwordlist', 'PREFIX_MIN_LENGTH', 1);
ctx_ddl.set_attribute ('nbcwordlist', 'PREFIX_MAX_LENGTH', 64);
ctx_ddl.set_attribute ('nbcwordlist', 'SUBSTRING_INDEX', 'NO');
END;
CREATE INDEX FTS_IDX ON INDVL_SRCH_NM (SRCH_NM)
INDEXTYPE IS CTXSYS.CTXCAT
PARAMETERS('STORAGE IDX_STORE STOPLIST C_STOPLIST WORDLIST C_WORDLIST')
PARALLEL (DEGREE 16);
What should be done to create this index in parallel? Is there any other thing that can be done to speed up creation without disabling prefix index.
Thanks. I appreciate you time and effort.
Edited by: spur230 on Nov 14, 2011 4:53 PM

Hi,
in the manual some remarks are made for parallel indexing, see http://download.oracle.com/docs/cd/E14072_01/text.112/e10945/ind.htm#CIHCBABI
So it is possible to index in parallel, but you don't have control, the oracle db decides this for you. So it is possible that Oracle thinks that single indexing is faster, more work is done in the database besides the index creation, and many more factors (also mentioned in above document).
I did many parallel indexing on systems, but always on quiet moments, so I have the most resources for creating indexes. Furthermore I noticed that system statistics can influence the creation. If the statistics are good for the CPU and I/O, the parallel creation can be optimised by the db.
Herald ten Dam
http://htendam.wordpress.com

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