Environment: mysql 5.7
transaction isolation level repeatable read
table is as follows:
:
: id = 2 
:
SQL
my question is: why does my session need to be submitted again in order to view the updated data of session II?
No for update. Is to simply open two transactions. Session 2 updates the data and commits the transaction. Session 1 commits the transaction and looks at the data. It is
that you can see the data updated by session 2.whether changes can be seen during a transaction session is related to the isolation level of the transaction.
see the official documentation:
https://dev.mysql.com/doc/ref.
by default, REPEATABLE READ, is readable repeatedly, that is, multiple reads during a transaction return the same result.
BTW:
the four isolation levels defined by mysql do not have repetable commit this.
there is only
on the official website.level:
REPEATABLE READ
READ COMMITTED
READ UNCOMMITTED
SERIALIZABLE
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