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Sorry, I just start to lean kylin

When I execute the sql select * from kylin_sales where price > 2 in default sample cube of kylin, it failed with the message

ERROR while executing SQL "select * from kylin_sales where price > 2 LIMIT 50000": Can't find any realization. Please confirm with providers SQL digest: fact table DEFAULT.KYLIN_SALES,group by [],filter on[DEFAULT.KYLIN_SALES.PRICE],with aggregates[].

anybody knows the reason? Thanks

conia
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1 Answers1

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Kylin is a MOLAP (multidimensional online analytical processing) engine. It divides columns into dimensions and measures, expects queries to filter by dimensions and return aggregated measures.

Your query select * from kylin_sales where price > 2 does not work, because price is not a dimension thus is not suitable for filtering. Also the query does not select any aggregated measures.

A simple MOLAP query is like select week_beg_dt, sum(price) from kylin_sales where meta_categ_name='Collectibles' group by week_beg_dt

Kylin also supports a special type of RAW measure, that allows filter such as price > 2, but that's not demonstrated by the sample cube.

Li Yang
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