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@@ -77,16 +77,17 @@ meaning that if a migration fails to apply you will have to manually unpick
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the changes in order to try again (it's impossible to roll back to an
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earlier point).
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-In addition, MySQL will fully rewrite tables for almost every schema operation
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-and generally takes a time proportional to the number of rows in the table to
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-add or remove columns. On slower hardware this can be worse than a minute per
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-million rows - adding a few columns to a table with just a few million rows
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-could lock your site up for over ten minutes.
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-
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-Finally, MySQL has relatively small limits on name lengths for columns, tables
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-and indexes, as well as a limit on the combined size of all columns an index
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-covers. This means that indexes that are possible on other backends will
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-fail to be created under MySQL.
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+MySQL 8.0 introduced significant performance enhancements for
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+`DDL operations`_, making them more efficient and reducing the need for full
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+table rebuilds. However, it cannot guarantee a complete absence of locks or
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+interruptions. In situations where locks are still necessary, the duration of
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+these operations will be proportionate to the number of rows involved.
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+
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+Finally, MySQL has a relatively small limit on the combined size of all columns
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+an index covers. This means that indexes that are possible on other backends
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+will fail to be created under MySQL.
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+
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+.. _DDL operations: https://dev.mysql.com/doc/refman/en/innodb-online-ddl-operations.html
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SQLite
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------
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Nicolas Lupien