mysql - Does InnoDB have static tables? -

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i reading mysql documentation , wondering whether myisam's "static" table format applies on innodb or not? gain performance, if use char instead of varchar when real lengths varies between 0 , 100 characters or using varchar(100) better?

innodb have fixed-width rows , there can advantage declaring columns in table fixed-width. main benefit "holes" in page can reused insertion, since rows same length. makes space re-use more efficient. not try force fixed-width strings on few dozen bytes though, cost of storing data per page (and fewer rows per page) overwhelm savings/gains you'd more efficient space re-usage.

however, having fixed-width rows not allow optimization of row-scanning (like myisam) whatsoever. innodb's row storage page-based , uses b+tree doubly-linked lists of pages, , singly-linked records within page. row traversal using these structures , can't done other way.


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