ORA-20000: function-based index "XDB"."XDB$ACL_XIDX" is disabled

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## Error
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DBMS_STATS: GATHER_STATS_JOB encountered errors.  Check the trace file.
Errors in file /u01/app/oracle/product/admin/ORALIN/diag/rdbms/ORALIN/ORALIN3/trace/ORALIN3_j000_25372.trc:
ORA-20000: function-based index "XDB"."XDB$ACL_XIDX"  is disabled

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#  Error Occurred
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This database is newly created and Error occured while auto Gather statistics Collection job is run in 11.2.0.4.0 version

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## Command Executed
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Gather stats command

**************************************** Step By Step Analysis ******************************************************

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# 1) Check XDB Registry and Index Status
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#### Check Database registry

SELECT comp_id,COMP_NAME,schema,VERSION,STATUS,MODIFIED FROM DBA_REGISTRY where comp_id='XDB';

COMP_ID         COMP_NAME                           SCHEMA          VERSION         STATUS          MODIFIED
--------------- ----------------------------------- --------------- --------------- --------------- -------------------------
XDB             Oracle XML Database                 XDB             11.2.0.3.0      VALID           09-FEB-2015 10:23:02

#### Check the index

select owner, index_name, status, funcidx_status from dba_indexes where index_name = 'XDB$ACL_XIDX';

OWNER                          INDEX_NAME                     STATUS          FUNCIDX_
------------------------------ ------------------------------ --------------- --------
XDB                            XDB$ACL_XIDX                   VALID           DISABLED

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#########################################
# 2) Reason for Failure
#########################################

Newly created database started giving these errors, looks like there is some problem with the installation which we have used is DBCA.

Most of the Database registry were in INVALID state. Made all the database components VALID and found the above error is occuring, which is due to the function based index in DISABLED state.

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## Solution
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#### Enable the index

Alter index xdb.xdb$acl_xidx enable;

SQL> Alter index xdb.xdb$acl_xidx enable;
Index altered.

SQL> select owner, index_name, status, funcidx_status from dba_indexes where index_name = 'XDB$ACL_XIDX';

OWNER                          INDEX_NAME                     STATUS          FUNCIDX_
------------------------------ ------------------------------ --------------- --------
XDB                            XDB$ACL_XIDX                   VALID           ENABLED

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Now the GATHER stats job was running without any errors.
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 Comments Are Always welcome
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