Re: Calculate bytes stored per row for dynamic format

[Rick James]

Overhead per row: 1-2 bytes (2 if utf8, not because of charset, but because it could be longer than 255 bytes.)
BIGINT: 8 bytes
VARCHAR(150), if Ascii or latin1: 1-151 bytes
VARCHAR(150), if utf8: 2-452 bytes
NULL (if any columns are NULLable): 1 byte

100K rows -- at least 1MB (tiny); worst case: 46.3MB (medium sized). Even at 46MB, 1/3 of the tables discussed here are bigger than that.

INDEX size -- that's another formula; do you need that, too?

If you DELETE or UPDATE rows, the math gets more complex.

Why have a BIGINT? INT (4 bytes) is big enough for most uses.
INT UNSIGNED can hold values 0..4 billion.