Fix InnoDB critical bug #7496; we scan the InnoDB data dictionary also at a normal mysqld startup, and create the spaces, so that we know the mapping space id -> .ibd file name; fix an infinite loop if DISCARD TABLESPACE coincides with INSERT or some other table operation; fix a potential crash if DISCARD TABLESPACE coincides with a cascaded FOREIGN KEY operation in the same table; do not allow DISCARD TABLESPACE of a referenced table if FOREIGN_KEY_CHECKS=1
Fix bug: if there was little file I/O in InnoDB, but the insert buffer was used, it could happen that 'Pending normal aio reads' was bigger than 0, but the I/O handler thread did not get waken up in 600 seconds. This resulted in a hang, and crashing of InnoDB.
Multiple tablespaces for InnoDB
sql_table.cc:
Tell explicitly that InnoDB should retrieve all columns in CHECKSUM TABLE
sql_update.cc, sql_select.cc, my_base.h:
More descriptive flag name HA_EXTRA_RETRIEVE_ALL_COLS
