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SQL (DQL (where (between (! inclusive), in (performance), like (like '…

- - - - ! inclusive
    - - performance
    - - like '%bird%'
  - - - select * from employee join department
    - - select * from employee e [inner] join department d on e.dept_id = d.dept_id
    - - database optimizer choose the best order, BUT it is possible to provide a hint and set DRIVING TABLE (the first table)
- - - - varchar == text and recommended
      - character(n) is slowest and requires extra space
- - - - read uncommited
      - read commited
      - repeatable read
      - serializable
    - - dirty reads (uncommited dependency)
      - non-repeatable reads
      - phantom reads