spring data jpa
basic idea and operation orm hibernate and jpa jpa and an overview of: DAY1
DAY2: springdatajpa operating principle and basic operation
day3: multi-table operation, complex queries
The basic idea and operation orm jpa and hibernate and jpa overview of: day1
The first thought orm
main purpose: operating entity class is equivalent to the operation of the database table
to establish the relationship between two maps:
the entity classes and relational tables mapping
entity class mapping between properties and fields in the table
is no longer the focus of attention: specific sql statement
to achieve ORM framework of thinking: mybatis, hibernate
The second frame hibernate describes
Hibernate is an object-relational mapping framework for open source,
it is encapsulated JDBC,
it POJO establish the mapping between database tables, it is a fully automatic orm frame.
The third JPA specification
JPA stands Java Persistence API, jpa ORM is set based on the specification, by the internal interfaces and abstract classes.
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