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What extended stats do I have on my database?

I've been starting to work with Extended statistics to help the optimizer find the best plan. This is a great feature that is outlined by @sqlmaria (Maria Coogan) here.

But once you create extended statistics, how do you know what is there ?  I wrote this query to find out what function based indexes, what extended statistics, and what their definition are. 

Here is my script.

column table_owner alias "owner" format a15
column table_name alias "Table Name" format a30
column function_index alias "F Index" format a8
column Index_name alias "Index Name" format a30
column data_default alias "Definition" format a50
set pagesize 1000
select table_owner,
table_name,
nvl2(index_name,'YES','NO') function_index,
index_name,
data_default
from
(
select owner table_owner,table_name,
(select distinct index_name from dba_ind_columns b where a.column_name=b.column_name and a.owner=b.index_owner and a.table_name=b.table_name) index_name
,data_default
-- , DBMS_LOB.SUBSTR( to_lob(data_default),100,1)
from dba_tab_cols a
where virtual_column='YES' and hidden_column='YES' and (owner not in ('SYS','WMSYS','XDB','SYSMAN','MDSYS','EXFSYS','PR_MDS') and owner not like 'APEX_%')
)
order by table_owner,table_name;


and this is what the output looks like..

TABLE_OWNER     TABLE_NAME                     FUNCTION INDEX_NAME                     DATA_DEFINITION
--------------- ------------------------------ -------- ------------------------------ --------------------------------------------------
BGRENN TAB_SCHR_PERD NO COALESCE("COL1","COL2")
BGRENN TAB2 YES IDX_TAB2 "COL1"||' '||"COL2"
BGRENN TAB3 NO COALESCE("COL1","COL2")
BGRENN TAB4 YES IDX_TAB4 COALESCE("COL1","COL2",0)
BGRENN TAB4 YES IDX_TAB4 COALESCE("COL3",0)
BGRENN TAB5 YES IDX_TAB5 COALESCE("COL1","COL2",0)
BGRENN TAB6 YES IDX_TAB6 NVL("COL1",(-1))
BGRENN TAB6 YES IDX_TAB6 NVL("COL2",(-1))
BGRENN TAB6 YES IDX_TAB6 NVL("COL3",(-1))
BGRENN TAB6 YES IDX_TAB6 NVL("COL4",'x')
BGRENN TAB7 YES IDX_COMPOSITE "COL1"
BGRENN TAB7 YES IDX_COMPOSITE "COL3"

Notice the Function colunmn. This is a "YES" or "NO" depending on if this is a function based index, or just extended statistics.

This should help tell where your extended statistics are in your database.

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