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From Martin Pernollet <mpernol...@octo.com>
Subject Re: EXPLAIN has similar output for filters on indexed and non-indexed column
Date Mon, 06 Jul 2015 14:05:51 GMT
Thank you.

Actually I am querying an indexed column so I believe it is implicitely
covered?

I mean I should not have to call :

Create index IDX on TABLE(COL1) include (COL1)


Le mer. 1 juil. 2015 à 20:18, Gerber, Bryan W <Bryan.Gerber@pnnl.gov> a
écrit :

>  Phoenix doesn’t support automatically using index on a non-covered
> query. Check out https://phoenix.apache.org/secondary_indexing.html for
> some examples. Your query may have been faster due to more data being
> cached.
>
>
>
> The 2-step plan you’re looking for in this case looks more like this one
> where I used a hint to specify the index:
>
> | CLIENT 40-CHUNK PARALLEL 40-WAY FULL SCAN OVER LOG |
>
> |     SKIP-SCAN-JOIN TABLE 0               |
>
> |         CLIENT 40-CHUNK PARALLEL 40-WAY FULL SCAN OVER LOG_REQUEST_IDX |
>
> |             SERVER FILTER BY FIRST KEY ONLY AND "RQ" LIKE '/jquery%' |
>
> |     DYNAMIC SERVER FILTER BY ("LOG.TS", "LOG.F", "LOG.R") IN
> (($707.$709, $707.$710, $707.$711)) |
>
>
>
>
>
> *From:* Martin Pernollet [mailto:mpernollet@octo.com]
> *Sent:* Wednesday, July 01, 2015 6:06 AM
> *To:* user@phoenix.apache.org
> *Subject:* EXPLAIN has similar output for filters on indexed and non
> indexed column
>
>
>
> Hi,
>
>
>
> I want to perform :
>
> SELECT * FROM "table" where "family"."column1" = 'value'
>
>
>
> Running an EXPLAIN on this request before creating an index on a column
> gives :
>
>
>
> CLIENT PARALLEL 1-WAY FULL SCAN OVER table
>
>   SERVER FILTER BY family.column1 = 'value'
>
>
>
> Looks OK.
>
> Then I simply :
>
> CREATE INDEX "table_IDX_column1" on "table" ("family"."column1");
>
>
>
> Following requests using a filter on indexed column are definitely faster.
>
>
>
> However, when *running EXPLAIN again I have exactly the same output*
> mentioning a full scan.
>
>
>
> I am not familiar with Phoenix explain plan, but I would expect 1 GET on
> the index table, and then 1 get in my main table. Isn't it?
>

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