mysql basic interview questions

1, uuid and id difference

  . 1) UUID type varchar (36), and since it is generally bigInt Id growth type.

  2) the physical space uuid type of self-consumed bigInt growth Id, varchar (36) with respect to type more pronounced. 

  3) uuid almost guarantee a unique id different tables in different databases, and since growth can only be guaranteed id id only one database in a table of
      the database of words and then merge will fail because the primary key violation, which is a Mishap . 

2, the main increase from the database how to check against a database, modify the master database from

  1) from the master database update operation itself is the master table, the table lookup operation, the separation from the master, data synchronization

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Origin www.cnblogs.com/jiaxinzhu/p/12466852.html