microservices Sixth springboot Configuring Oracle data sources via SPRING-DATA-JPA (SPRING-DATA-JPA details)

The Jpa:java persistence API is a Java persistence specification. It provides Java developers with an object/mapping tool to manage relational data in Java applications. The goal is to simplify persistent development efforts and integrate ORM technology.

Spring Data JPA is a set of JPA application frameworks encapsulated on the basis of the ORM framework and JPA specifications of spring. Enables developers to access and manipulate data with minimalist code.

Spring Data JPA generates some basic additions and deletions by default.

    List<t> findAll ();    List<t> findAll (Sort var1);    List<t> findAll (iterable<id> var1);    <s extends t> list<s> Save (iterable<s> var1);    void Flush ();    <s extends t> s Saveandflush (S var1);    void Deleteinbatch (iterable<t> var1);    void Deleteallinbatch ();    T GetOne (ID var1);    <s extends t> list<s> findAll (example<s> var1);    <s extends t> list<s> findAll (example<s> var1, Sort var2);

　　

Custom Actions:

Specific keywords, using methods and production into SQL are shown in the following table

Keyword	Sample	JPQL Snippet
and	Findbylastnameandfirstname	... where x.lastname =? 1 and x.firstname =? 2
Or	Findbylastnameorfirstname	... where x.lastname =? 1 or x.firstname =? 2
Is,equals	Findbyfirstnameis,findbyfirstnameequals	... where x.firstname =? 1
Between	Findbystartdatebetween	... where x.startdate between? 1 and? 2
LessThan	Findbyagelessthan	.. where X.age <? 1
Lessthanequal	Findbyagelessthanequal	... where x.age?? 1
GreaterThan	Findbyagegreaterthan	.. where X.age >? 1
Greaterthanequal	Findbyagegreaterthanequal	... where x.age >=? 1
After	Findbystartdateafter	.. where X.startdate >? 1
Before	Findbystartdatebefore	.. where X.startdate <? 1
IsNull	Findbyageisnull	... where x.age is null
Isnotnull,notnull	Findbyage (IS) notnull	... where x.age not null
Like	Findbyfirstnamelike	... where x.firstname like? 1
Notlike	Findbyfirstnamenotlike	... where x.firstname not? 1
Startingwith	Findbyfirstnamestartingwith	... where x.firstname like? 1 (parameter bound with appended%)
Endingwith	Findbyfirstnameendingwith	... where x.firstname like? 1 (parameter bound with prepended%)
Containing	Findbyfirstnamecontaining	... where x.firstname like? 1 (parameter bound wrapped in%)
By	Findbyageorderbylastnamedesc	... where x.age =? 1 ORDER BY X.lastname DESC
Not	Findbylastnamenot	.. where X.lastname <>? 1
Inch	Findbyagein (Collection Ages)	... where x.age in? 1
Notin	Findbyagenotin (Collection Age)	... where x.age not in? 1
TRUE	Findbyactivetrue ()	... where x.active = True
FALSE	Findbyactivefalse ()	... where x.active = False
IgnoreCase	Findbyfirstnameignorecase	... where UPPER (x.firstame) = UPPER (? 1)

Custom SQL queries

In fact, the majority of the SQL in spring data can be implemented according to the method name definition, but for some reason we want to use a custom SQL to query, spring data is also the perfect support, the SQL query method above the use of @query annotations, If the deletion and modification are involved in the need to add @modifying. Can also be added as needed @Transactional support for things, query time-out settings, etc.

@Modifying @query ("Update User u set u.username =? 1 where u.id =? 2") int Modifybyidanduserid (String  userName, Long ID) ; @Transactional @modifying@query ("Delete from User where id =? 1") void Deletebyuserid (Long id);  @Transactional (timeout = ten) @Query ("Select u from user u where u.emailaddress =? 1")    User findbyemailaddress (String em ailaddress);

　　

microservices Sixth springboot Configuring Oracle data sources via SPRING-DATA-JPA (SPRING-DATA-JPA details)