Interview question bank (6): database related

• Mysql index data structure, indexing principles
• The difference between InnoDB and myiasm, and common mysql optimization solutions
• sql query optimization
• Let’s talk about SQL optimization of Mysql
• MySQL index, whether the b+ tree index supports range query, and the failure of the joint index
• What databases were used in development? Answer mysql, what are the storage engines? Then he asked me about the usage scenarios of pessimistic locking and optimistic locking, and the principles of distributed cluster implementation.
• Database index principles
• mysql index B+ tree principle
• How is mysql index implemented? What are the characteristics of b+ trees? Where does the real data exist? Under what circumstances should an index be built? Explain the leftmost matching principle? Now a table has three columns abc. When querying the combined index (a, b, c) where a like ? and b=? and c=? can this combined index be used? Why
• Have you seen the explain execution plan? What are the values ​​of the type field? What do they represent? Answer: #8
• How should sub-databases and tables be divided? How to solve the problem of data migration?
• Database index, multi-level index
• What are the isolation levels of database transactions? Mysql default isolation level? How are different isolation levels implemented? Have you ever used mysql explain? Let’s talk about the slow query of the database? Let’s talk about pessimistic and optimistic locking in databases. When is it more appropriate to use optimistic locking? When to use pessimistic locking?
• Let’s talk about two common storage engines in MySQL and applicable scenarios------Comparison between MyISAM and InnoDB