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From Mikhail Fokanov <wmas...@mail.ru>
Subject Re[2]: Polymorphic SQL queries
Date Tue, 27 Dec 2016 13:31:41 GMT
Thanks a lot, Sergi. I store the data in the same cache. Could you explain a little more extensively,
what should I change in configuration of cache in order to use Binary types of different
structure with the same binary type?

About CROSS join: I mean that queries like SELECT * FROM Person, City is cross joins (https://ru.wikipedia.org/wiki/Join_(SQL)#CROSS_JOIN)

Best Regards,
Mikhail Fokanov

>Вторник, 27 декабря 2016, 15:13 +03:00 от Sergi Vladykin <sergi.vladykin@gmail.com>:
>Right now I see only one way to store different value types in the same SQL table: you
can use Binary types of different structure with the same binary type and store them in the
same cache.
>I did not find anything about CROSS joins in our docs, may be you have confused it with
cross-cache join? Because we actually do support INNER and OUTER joins. 
>2016-12-27 14:48 GMT+03:00 Mikhail Fokanov  < wmaster@mail.ru > :
>>               I use Apache Ignite for high-loaded portal. Performance of
SQL queries are ok, but I can't find a way of implementing polymorphic SQL queries. I need
to index all sub-classes of the class in SINGLE_TABLE strategy (ex. ImageFile, PdfFile as
sub-classes of File), in order to execute queries like (select * from File where createdDate
> 0). For such query I can use "union all" and search all sub-classes, but now the amount
of sub-classes is 15 and this solution looks bad. Also I need to join User table with File
table and I think "union all" will be bad for performance in such case. Am I right? I try
to manage Query Entities in CacheConfiguration, but have no success. Can I implement some
hack to store entities of all sub-classes in the same table (File) and execute queries on
>>               Also I mention that in guide ( http://apacheignite.gridgain.org/docs/sql-queries
) sql joins are always CROSS. Can I use INNER joins and does it improve the performance of
>>Best Regards,
>>Mikhail Fokanov

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