jooq

摘要 介绍JOOQ简单实用，以及相对于传统ORM框架的不同点。 正文 JOOQ是啥？ JOOQ 是基于Java访问关系型数据库的工具包，轻量，简单，并且足够灵活，可以轻松的使用Java面向对象语法来实现各种复杂的sql。对于写Java的码农来说ORMS再也熟悉不过了，不管是Hibernate或者Mybatis，都能简单的使用实体映射来访问数据库。但有时候这些 ‘智能’的对象关系映射又显得笨拙，没有直接使用原生sql来的灵活和简单，而且对于一些如：joins,union, nested selects等复杂的操作支持的不友好。JOOQ 既吸取了传统ORM操作数据的简单性和安全性，又保留了原生sql的灵活性，它更像是介于 ORMS和JDBC的中间层。对于喜欢写sql的码农来说，JOOQ可以完全满足你控制欲，可以是用Java代码写出sql的感觉来。就像官网说的那样 : get back in control of your sql 这货有啥优点 JOOQ 目前在国内还是很小众，第一次听说这玩意还是通过 stream 大神 的推荐。对于从 SSH 成长起来的猿类来说，心里也会质疑 “这玩意用的人那么少，靠不靠谱” ，“会不会有很多坑要踩”。通过对着官方文档写了几个demo，顿时心生敬畏，一个念头冲到脑袋 " 这东西一定会火"，于是果断在项目中使用。在使用过程中也会遇到各种小问题

最近在翻阅springboot官方文档时，看见官方文档中有推荐一款ORM框架——jOOQ,可能很多朋友和我一样都没有用过这款框架，于是百度了一下，发现用过的朋友的都说它在代码层面比Mybatis简洁得多，而且性能也非常优异，抱着学习的态度，通过查询相关资料，在本地写了一个demo工程，体验了一下，在此记录一下。demo基于springboot 2.2.0,jooq相关组件版本为3.12.1 创建springboot工程，引入jooq的starter pom.xml <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jooq</artifactId> </dependency> 引入jooq插件依赖 <dependency> <groupId>org.jooq</groupId> <artifactId>jooq-meta</artifactId> </dependency> <dependency> <groupId>org.jooq</groupId> <artifactId>jooq-codegen</artifactId> </dependency> plugin配置 <plugin> <groupId>org.jooq</groupId>

刚刚入职公司用到了jooq，就上网找了几篇文章学习一下。 参考： https://segmentfault.com/a/1190000006748584?utm_source=tuicool&utm_medium=referral 官网 JOOQ是什么 jooq(Java Object Oriented Querying)java面向对象查询，是一种ORM框架，轻量，简单并且足够灵活。对于写Java的码农来说ORMS再也熟悉不过了，不管是Hibernate或者Mybatis，都能简单的使用实体映射来访问数据库。但有时候这些对象关系映射又显得笨拙，没有直接使用原生sql来的灵活和简单，而且对于一些复杂的操作支持的不友好。JOOQ 既吸取了传统ORM操作数据的简单性和安全性，又保留了原生sql的灵活性，它更像是介于 ORMS和JDBC的中间层。对于喜欢写sql的码农来说，JOOQ可以完全满足你控制欲，可以是用Java代码写出sql的感觉来。就像官网说的那样 : get back in control of your sql JOOQ的优点 通过官网和一些文章总结优点如下： 代码够简单和清晰。遇到不会写的sql可以充分利用IDEA代码提示功能轻松完成。 保留了传统ORM 的优点，简单操作性，安全性，类型安全等。不需要复杂的配置，并且可以利用Java 8 Stream API

I'm creating an interface of JOOQ TableRecord <R extends TableRecord<R>> Would anyone be able to explain the line above? Thanks It means a class of type R, that implements the interface TableRecord<R> TableRecord<R> means that the interface is bound to the same type R. An example would be a class like: public class Bla implements TableRecord<Bla> I admit this seems a bit strange, but Java generics don't really differentiate between extends and implements , which leads to some confusion. As to why this exact definition, I don't know enough about the context to see exactly why it makes sense,

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: In jOOQ if I want to fetch a row of a table into a jOOQ autogenerated POJOs I do, for instance: dsl . selectFrom ( USER ) . where ( USER . U_EMAIL . equal ( email )) . fetchOptionalInto ( User . class ); Now, suppose that I want to do a join between two tables, e.g. USER and ROLE , how can I fetch the result into the POJOs for these two tables? 回答1: This is one solution using ResultQuery.fetchGroups(RecordMapper, RecordMapper) Map < UserPojo , List < RolePojo >> result = dsl . select ( USER . fields ()) . select ( ROLE . fields ())

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: Jooq currently does not support JSR 310 types and support will not come until v3.8 . Using simple converters generally works, except for certain types, such as postgres' TIMESTAMP WITH TIME ZONE , which requires a custom binding. So I have tried to write one but the generated XxxRecord classes still use a Timestamp data type for the TIMESTAMP WITH TIME ZONE fields in my DB. What do I need to change in my code below to see postgres' TIMESTAMP WITH TIME ZONE as an Instant in jooq's generated classes? Converter public class

I define a type T and a view V in a PostgreSQL database. CREATE TYPE my_type AS ( mt_column1 smallint NOT NULL ); CREATE VIEW my_view AS SELECT some_column_id integer ARRAY(SELECT ROW(an_int)::my_type FROM a_table ) AS my_view_types FROM a_regular_table WHERE my_condition_hold); Using the code generation on release 3.7 I get both an UDT record class MyTypeRecord and a table record class MyViewRecord and the UDT POJO class MyType and table POJO class MyView . The MyView generated class has an array of MyTypeRecord . public class MyView extends Object implements Serializable, Cloneable, IMyView

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Lets say I have a table Person(id, fname, lname) and it contains a record (1, 'Michael', 'Bay') . Now I wish to create another record in Person table with the same fname and lname but different id i.e. (453456, 'Michael', 'Bay') . This is the way I would do in plain SQL INSERT INTO Person(id, fname, lname) SELECT 453456, Person.fname, Person.lname FROM Person WHERE Person.id = 1; How can this be done with JOOQ (ideally while retaining JOOQ's code generation and type safety features)? I am aware that JOOQ provides ability to copy entire