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[Philip Stoev <890694@xxxxxxxxxxxxxxxxxx>]

Public bug reported:

For a certain small class of optimizer bugs, simplification that removes
all unnecessary columns produces an non-repeatable test case. The reason
is that the total record length decreases, making full table scans more
likely.

Therefore, simplification should try to either remove all columns, or
replace them with a single CHAR() column whose length is equal to the
sum of the length of the removed columns.

** Affects: randgen
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/890694

Title:
  Simplification may need to preserve record length

Status in SQL Generator for testing SQL servers (MySQL, JavaDB, PostgreSQL):
  New

Bug description:
  For a certain small class of optimizer bugs, simplification that
  removes all unnecessary columns produces an non-repeatable test case.
  The reason is that the total record length decreases, making full
  table scans more likely.

  Therefore, simplification should try to either remove all columns, or
  replace them with a single CHAR() column whose length is equal to the
  sum of the length of the removed columns.

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