Hello ,
          I suppose the InnoDB tables in Mysql have REPEATABLE-READ as the 
default isolation. Is the concurrency enforced automatically by the database or 
is there anything 
the application programmer has to do to make sure the data consistent.


How does the REPEATABLE-READ resolve the following scenario.


User1 opens a application and reads a row on the screen.
User2 opens the same application and read the same row on the screen.


User2 updates a field (and commits ,as the autocommit is on),
User1 still is reading the non-updated row , and updates the same field updated 
by the User2 to different value.


How does  it affect the database when normal select , update queries are used.


What should the application programmer to enforce database concurrency.


Thank you,
Vinay






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