Index on a COALESCE function

, Hi, I'm trying to index on a coalesce function:

The index definition is CREATE INDEX emailrcpts_cid_coalesce_dtofpurch"
btree (cid, (COALESCE(date_of_purchase, '1900-01-01'::date)))

A portion of the query I am trying to optimize follows:

select 45198705,false,id,next_avail_senddate(id,date(send_date)) from

(select
id,timeclause_combine(date(estmileage_timeclause(service_date,mileage,last_s
ervice_date,last_mileage,

date_of_purchase,year_purchased,10750,cid,serindex_date,id)),

date(date_larger(date(coalesce(date_of_purchase,
'1900-01-01')+timespan('45 days')),

date(service_date+timespan('44 days')))),

date(null),date(create_date),9,false) as send_date,last_send

I can't seem to get this index to work on the function, just on the cid
column. Any ideas would be appreciated

Thank you,

Mark Steben

Senior Database Administrator
@utoRevenueT
A Dominion Enterprises Company
480 Pleasant Street
Suite B200
Lee, MA 01238
413-243-4800 Home Office
413-243-4809 Corporate Fax

msteben <blocked::mailto:name(at)autorevenue(dot)com> @autorevenue.com

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