mysql - Make subquery with like -

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i have following 2 tables. how can make query table b variant_id matched in table combination?

tablea product_id  combination     ean 1           952_4038        123456789 2           946_3989        101010101  tableb variant_id  desc 4038        text1 3989        text2

thanks!

select  a.*, b.*    tablea         inner join tableb b             on a.combination concat('%', b.variant_id)

this query terribly slow on large databases. consider normalizing table properly.

my proposed table schema:

tablea

  • productid (1)
  • intcolumn (952)
  • combination (4038)
  • ean (123456789)

tableb

  • combination (4038)
  • desccolumn (text) [don't use reserved keyword]

make sure have indexes on linking fields.

followup question: table main table , dependent table?


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