RE: Unique Index Re-design
- From: Sayan Sergeevich Malakshinov <malakshinovss@xxxxxxxxx>
- To: mohamed.houri@xxxxxxxxx
- Date: Fri, 28 Mar 2014 14:19:06 +0400
Hi Mohamed,
> create unique index mho_ind on t4 (case when a = 90996518 then null
else a end, case when b is not null then b end);
Strictly speaking, "case when b is not null then b end" will have same
values as just simple "b"
And you will need to rewrite predicates(or maybe create view like "create
view t4 select case when a = 90996518 then null else a end as A, ... from
old_t4" )
> When I asked the client what is the particularity of this a value
(90996518) he answered that this a dummy value used for testing (yes for
testing
> in PRODUCTION).
Am i right that all rows with such value are just dummy rows? In that
case, i think, we could consider table partitioning with separation dummy
rows from others and local indexing.
--
Best regards,
Sayan Malakshinov
http://orasql.org
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