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From Mich Talebzadeh <mich.talebza...@gmail.com>
Subject Re: Creating Index and no performance improvements
Date Thu, 27 Oct 2016 11:41:15 GMT
Have you checked running SQL with

EXPLAIN EXTENDED SELECT ......

And post the results.

In general your compact index will not work

HTH

Dr Mich Talebzadeh



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On 27 October 2016 at 12:34, Hilmi Egemen Cirito─člu <
hilmi.egemen.ciritoglu@gmail.com> wrote:

> Hi guys,
>
> I created table and index on this table. Also after I alter that index
> with rebuild option. But still can't see performance improvements.
>
> Only, I can see performance improvements when I query to index table.
>
> I used following commands :
>
> CREATE EXTERNAL TABLE testindex(wban INT, ndate STRING, time STRING,
> stationType STRING, skyCondition STRING, skyConditionFlag STRING,
> visibility INT,
> visibilityFlag INT, weatherType STRING, weatherTypeFlag STRING,
> dryBulbTempF INT, dryBulbTempFFlag INT, wetBulbTempF INT,
> wetBulbTempFFlag INT, wetBulbTempC DOUBLE, webBulbTempCFlag INT, dewPointF
> INT, dewPointFFlag INT, dewPointC INT, dewPointCFlag INT,
> relativeHumidity INT, relativeHumidityFlag INT, windSpeed DOUBLE,
> windSpeedFlag INT, windDirection STRING, windDirectionFlag INT,
> valueForWindCharacter STRING, valueForWindCharacterFlag INT,
> stationPressure DECIMAL, stationPressureFlag INT, pressureTendency INT,
> pressureTendencyFlag INT, pressureChange STRING, pressureChangeFlag INT,
> seaLevelPressure INT, seaLevelPressureFlag INT, recordType STRING,
> recordTypeFlag INT, hourlyPrecip DECIMAL, hourlyPrecipFlag INT, altimeter
> INT, altimeterFlag INT)
> ROW FORMAT DELIMITED
> FIELDS TERMINATED BY ','
> LINES TERMINATED BY '\n';
>
> LOAD DATA LOCAL INPATH '/home/user1/Downloads/dataset' INTO TABLE
> testindex;
>
> CREATE INDEX test ON TABLE testindex (ndate) AS 'COMPACT' WITH DEFERRED
> REBUILD;
> ALTER INDEX test ON testindex REBUILD;
>
> Do you know any reason behind this issue ?
>
> Any help would be highly appreciated...
>
> Thanks.
>

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