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    • Work in progress **

When doing a large ALTER TABLE (like when you need to increase the MAX_ROW table setting), you will want to up your myisam_sort_buffer_size (to as large as available RAM) and myisam_max_sort_file_size (to any very large number. Pick 100GB).

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Isotopp myisam_sort_buffer_size needs to be able only the largest index you have Isotopp not all of the myi Isotopp in general, a worst case estimate for index size is ( #of rows in index * 1.5 * index width ) Isotopp and index width is sum(size of cols in index) + 6 bytes row pointer AndyGore right Isotopp so alter table t add index ( i ) with i = integer not null will be 4+6 = 10 bytes wide. Isotopp with 1.5 mio rows thats 15*1.5 mio bytes Isotopp or 22.5 mb

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