• The direction of this in JavaScript (Introduction)


    Make a classification before writing. There are six situations: This in function//Point to the caller itself This in arrow function () = > {}//This is the closest function runtime at definition time This in call, bind, apply, etc//Point to the redirected this This of arrow function in call, bind, apply, etc//This is the closest function […]

  • Record lock, gap lock and next key lock under InnoDB


    prefaceIn fact, the record lock (also known as row lock), gap lock and next key lock under InnoDB are all exclusive locks. Row lock Record locks are actually easy to understand. Locking records in a table is called record locks, or row locks for short. Gap lock in life The idea of programming comes from […]