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ALGORITHM=INSTANT к синтаксису:ALTER TABLE table_name [alter_specification], ALGORITHM=INSTANT;
The benefit of the INSTANT algorithm is that only metadata changes are made in the data dictionary. There is no need to acquire metadata lock during SE changes and we don’t touch the data of the table.
mount -no remount,ro /dev/sdaX && swapoff -adebugfs -R "dump <8> /mnt/EXTERNAL_MEDIA/journal.copy" /dev/sdaXdd if=/dev/sdaX of=/mnt/EXTERNAL_MEDIA/partition.imageselect s1.name, s2.name from images s1
inner join
(
select t2.name, t2.phash as dup_phash, hamming_distance((t1.phash), (t2.phash)) as dist from images t1
inner join images t2 on dist between 1 and 8
group by dist
having count(*) > 1
) s2 on dist between 0 and 8
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