mysql - Multiple updates or update ... where in -

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which version better (performance)?

1. update my_table set my_col = 1 my_id = 100    update my_table set my_col = 1 my_id = 110    update my_table set my_col = 1 my_id = 120  2. update my_table set my_col = 1 my_id in (100, 110, 120)

in case, both ways have equal response time running 3-4 queries.
2nd way faster higher number of queries or updates (bulk updates faster) because reduce,

  1. creating,binding connections database
  2. query compilation/optimization task of sql engine

but bulk updates has 1 downside i.e. locking of tables updating multiple records in single statement, table locked duration. perform bulk updates considering acceptable locking period in mind.


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