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Question

How can i update this query, to give me more speed?

Why is the query slower, when I use JOIN?

SELECT v.vare_id, 
       LEFT(v.varenavn, 25) as varenavn, 
       v.salgspris, 
       ve.enhed, 
       ve.vare_enhed_id, 
       vt.tilstand, 
       vt.vare_tilstand_id, 
       v.oko_vare, 
       v.varefoto
FROM vare v

JOIN vare_enhed_valg vev
  ON vev.vare_id = v.vare_id

JOIN vare_enhed ve
  ON ve.vare_enhed_id = vev.enhed_id

JOIN vare_tilstand_valg vtv
  ON vtv.vare_id = v.vare_id

JOIN vare_tilstand vt
  ON vt.vare_tilstand_id = vtv.tilstand_id

WHERE v.vare_type_id = 1
  AND v.synlig = "ja"

ORDER BY v.varenavn ASC

Answer 1

For your query, you want an index on: vare(vare_type_id, v.synlig, v.varenavn) . Other indexes might be appropriate. Let me assume that the join keys include the primary key of at least one of the tables.