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Editorial Team
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Asked: 2026-06-14T03:50:19+00:00

A partial index helps to have smaller indexes, and makes INSERTs faster. For instance

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A partial index helps to have smaller indexes, and makes INSERTs faster.

For instance

  CREATE TABLE wine (
    name VARCHAR(100),
    ...
    INDEX (name(8)));

While names are something like

  Chateau Mouton-Rothschild
  Chateau Mouton-Cadet
  Chateau Petrus
  Chateau Lafite
  Chateau Lafleur
  ...

In this (example) list, Chateau appears all the time, MySQL creates an index based on the 8 first characters… meaning there will be only one entry in the index (and the search of Chateau Petrus will be done sequentially for all Chateau).
(In this very case, a split between the first word (Chateau) and the rest of the name in two fields would make sense, but this is not the point).

Is there a way to ask MySQL to create a partial index based on the end of a field?

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1 Answer

  1. Editorial Team

    Actually I found a way in the meantime – with a bit of programming:

    Only for the name field

    • all name entries are stored reverse in the DB
    • all name searches are made reverse
    • name in row is reversed before being sent to client (user agent)

    For instance in PHP

    • ...query('INSERT ... name="' . strrev($name) . '"...
    • ...query('SELECT * FROM wine WHERE name="' . strrev($name) . '"');
    • and for instance a search of %MOUTON% will actually search %NOTUOM%

    There is a bit of reverse overhead, but is negligible compared to the possible database gain.

    The question was specifically asking for a pure MySQL solution, but if there is none, this is a workable workaround in any language. I’ll accept this answer in a few days if there is nothing better.

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