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Asked: 2026-06-15T23:54:51+00:00

While searching trough SO, I’ve found two contradicting answers (and even a comment that

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While searching trough SO, I’ve found two contradicting answers (and even a comment that stated that) but no definitive answer:

The problem is: is there any performance benefit, if you store a TEXT/BLOB field outside of a table?

We assume:

  • You SELECT correctly (only selection the TEXT/BLOB if required, no SELECT *)
  • Tables are indexed properly, where it makes sense (so it’s not a matter of ‘if you index it’)
  • The database design doesnt really matter. This is a question to identify the MySQL behaviour in this special case, not to solve certain database design problems. Let’s assume this Database has only one table (or two, if the TEXT/BLOB gets separated)
  • used engine: innoDB (others would be interesting too, if they fetch different results)

This post states, that putting the TEXT/BLOB into a separate table, only helps if you’re already SELECTing in a wrong way (always SELECTing the TEXT/BLOB even when it’s not necessary) – basically stating, that TEXT/BLOB in the same table is basically the better solution (less complexity, no performance hit, etc) since the TEXT/BLOB is stored seprately anyway

The only time that moving TEXT columns into another table will offer any benefit is if there it a tendency to usually select all columns from tables. This is merely introducing a second bad practice to compensate for the first. It should go without saying the two wrongs is not the same as three lefts.

MySQL Table with TEXT column

This post however, states that:

When a table has TEXT or BLOB columns, the table can’t be stored in memory

Does that mean that it’s already enough to have a TEXT/BLOB inside a table, to have a performance hit?

MySQL varchar(2000) vs text?

My Question basically is: What’s the correct answer?

Does it really matter if you store TEXT/BLOB into a separate table, if you SELECT correctly?

Or does even having a TEXT/BLOB inside a table, create a potential performance hit?

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1 Answer

  1. Editorial Team

    Update: Barracuda is the default InnoDB file format since version 5.7.

    If available on your MySQL version, use the InnoDB Barracuda file format using

    innodb_file_format=barracuda

    in your MySQL configuration and set up your tables using ROW_FORMAT=Dynamic (or Compressed) to actually use it.

    This will make InnoDB to store BLOBs, TEXTs and bigger VARCHARs outside the row pages and thus making it a lot more efficient. See this MySQLperformanceblog.com blog article for more information.

    As far as I understand it, using the Barracuda format will make storing TEXT/BLOB/VARCHARs in separate tables not valid anymore for performance reasons. However, I think it’s always good to keep proper database normalization in mind.

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