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Re: Planner regression in 9.1: min(x) cannot use partial index with NOT NULL - Mailing list pgsql-hackers

From Greg Stark
Subject Re: Planner regression in 9.1: min(x) cannot use partial index with NOT NULL
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Msg-id AANLkTinc6f4xgKPOQd59zzmephnhi_3XY=8qMtN9WjGV@mail.gmail.com
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In response to Re: Planner regression in 9.1: min(x) cannot use partial index with NOT NULL  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Planner regression in 9.1: min(x) cannot use partial index with NOT NULL
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On Tue, Mar 22, 2011 at 4:35 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Reimplement planner's handling of MIN/MAX aggregate optimization (again).
>

I'm just curious, Why is this no longer an interesting special case?


--- this is an interesting special case as of 9.1
-explain (costs off)
-  select min(unique2) from tenk1 where unique2 = 42;
-                  QUERY PLAN
------------------------------------------------
- Aggregate
-   ->  Index Scan using tenk1_unique2 on tenk1
-         Index Cond: (unique2 = 42)



-- 
greg

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