ALTER TABLE - Setting MAX ROWS

From Hashmysql
Jump to: navigation, search
    • 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).


http://dev.mysql.com/doc/refman/5.0/en/full-table.html


http://dev.mysql.com/doc/refman/5.0/en/dynamic-system-variables.html


http://dev.mysql.com/doc/refman/5.0/en/alter-table.html


Integrate into Wiki

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

Fix Above

Retrieved from "http://hashmysql.net/w/index.php?title=ALTER_TABLE_-_Setting_MAX_ROWS&oldid=2957"