#14180: Creating redundant indexes on foreign keys  for MySQL/InnoDB tables
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 Reporter:  zimnyx           |       Owner:            
   Status:  new              |   Milestone:            
Component:  ORM aggregation  |     Version:  1.2       
 Keywords:                   |       Stage:  Unreviewed
Has_patch:  0                |  
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 During adding a foreign key contraint on InnoDB table, index is created
 automaticaly if it doesn't exist.

 ''
 (MySQL 5.x manual)
 "InnoDB requires indexes on foreign keys and referenced keys so that
 foreign key checks can be fast and not require a table scan. In the
 referencing table, there must be an index where the foreign key columns
 are listed as the first columns in the same order. Such an index is
 created on the referencing table automatically if it does not exist. (This
 is in contrast to some older versions, in which indexes had to be created
 explicitly or the creation of foreign key constraints would fail.)"
 ''

 After adding FK constraint, Django creates index for every FK, which just
 "overwrites" index that was created in background by InnoDB engine.
 It's a waist of time. It's not a big deal if you just run syncdb, but if
 you run unit tests waiting every time for those indexes be created is a
 bit annoying.

-- 
Ticket URL: <http://code.djangoproject.com/ticket/14180>
Django <http://code.djangoproject.com/>
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