This is Q about MySql - for reading about ascending or descending indices in MS SQL you can see here: SQL Server indices - ascending or descending, what's the difference? This refers to a different database and has a different answer.
Will specifying Asc or Desc by index in MySql speed up queries for items at the edges of the index?
If I have a table with an integer column and an index in this column, and I know that most of my queries in this field will look for high values, would it help if the index was defined as descending?
Will this cause earlier values to appear?
@AndreKR noted that this is actually not yet supported. Should I tag such an index as Desc , in the hope that in some future version it will become significant? Or should I ignore this option until it makes some real sense?
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