SQL dotaz

[Tom Meinlschmidt]

Ahoj,

a indexy nad tema tabulkama mas?

ukaz vysledek

explain select * from meta3 where… order by … 

tm

> On Nov 14, 2016, at 15:21 , Kosťa MK <kosta na cti.si> wrote:
> 
> Zdravím,
> 
> mám následující problém:
> 
> Nad databází mám vytvořen relativně složitý view:
> 
> CREATE VIEW meta3 AS SELECT id,
>                            title,
>                            (SELECT author_sort          FROM authors WHERE authors.id IN (SELECT author from books_authors_link WHERE book=books.id)) authors,
>                            (SELECT name                 FROM series WHERE series.id IN (SELECT series FROM books_series_link WHERE book=books.id)) series,
>                            series_index,
>                            (SELECT group_concat(name)   FROM tags WHERE tags.id IN (SELECT tag from books_tags_link WHERE book=books.id)) tags,
>                            (SELECT group_concat(value)   FROM custom_column_1 WHERE custom_column_1.id IN (SELECT value from books_custom_column_1_link WHERE book=books.id)) genre,
> 
>                            (SELECT group_concat(value)   FROM custom_column_2 WHERE custom_column_2.id IN (SELECT value from books_custom_column_2_link WHERE book=books.id)) type,
>                            path,
>                            (SELECT name                 FROM data WHERE data.book=books.id) file,
>                            (SELECT group_concat(format) FROM data WHERE data.book=books.id) formats,
> timestamp
>                            FROM books
> 
> funguje perfektně, jenže je zoufale pomalý pokud se pokusí o ORDER nad libovolným sloupcem
> 
> Mohl by mě pridím někdo nakopnout jak to zrychlit?
> 
> S pozdravem
> Kosta
> 
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-- 
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Tomas Meinlschmidt, MS {MCT, MCP+I, MCSE, AER}, NetApp Filer/NetCache

www.meinlschmidt.com  www.maxwellrender.cz 
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