关于java:mysql-lock

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intention lock 意向锁，表明有事务正在或者打算锁住一行记录
record lock 行所，分为排他锁和共享锁
gap lock 锁住索引之间的间隙
next key lock：record lock + gap lock

for example
id :0,5,10,15,20,25
unique,a
index,b

id=10
index_name lock_type lock_mode lock_status lock_data
NULL TABLE IX GRANTED NULL
PRIMARY RECORD X,REC_NOT_GAP GRANTED 10
a=10
index_name lock_type lock_mode lock_status lock_data
NULL TABLE IX GRANTED NULL
test_a_uindex RECORD X,REC_NOT_GAP GRANTED 10, 10
PRIMARY RECORD X,REC_NOT_GAP GRANTED 10
b=10
index_name lock_type lock_mode lock_status lock_data
NULL TABLE IX GRANTED NULL
test_t_index RECORD X GRANTED 10, 10
PRIMARY RECORD X,REC_NOT_GAP GRANTED 10
test_t_index RECORD X,GAP GRANTED 15, 15
id=11
index_name lock_type lock_mode lock_status lock_data
NULL TABLE IX GRANTED NULL
PRIMARY RECORD X,GAP GRANTED 15
a=11
index_name lock_type lock_mode lock_status lock_data
NULL TABLE IX GRANTED NULL
test_a_uindex RECORD X,GAP GRANTED 15, 15
b=11
index_name lock_type lock_mode lock_status lock_data
NULL TABLE IX GRANTED NULL
test_t_index RECORD X,GAP GRANTED 15, 15
id>11
index_name lock_type lock_mode lock_status lock_data
NULL TABLE IX GRANTED NULL
PRIMARY RECORD X GRANTED 0
PRIMARY RECORD X GRANTED 5
PRIMARY RECORD X GRANTED 10
PRIMARY RECORD X,GAP GRANTED 15
id<=11
index_name lock_type lock_mode lock_status lock_data
NULL TABLE IX GRANTED NULL
PRIMARY RECORD X GRANTED 0
PRIMARY RECORD X GRANTED 5
PRIMARY RECORD X GRANTED 10
PRIMARY RECORD X,GAP GRANTED 15

论断：
X:next key lock，也就是 recordlock+ previous gap
x gap:previous gap
x rec not gap: rec

正文完
java
发表至： java
2022-07-19
 0
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