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What's jOOQ
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jOOQ's reason for being - compared to JPA
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jOOQ stands for Java Object Oriented Querying. It combines these essential features:
Java and SQL have come a long way. SQL is an "ancient", yet established and well-understood technology. Java is a legacy too, although its platform JVM allows for many new and contemporary languages built on top of it. Yet, after all these years, libraries dealing with the interface between SQL and Java have come and gone, leaving JPA to be a standard that is accepted only with doubts, short of any surviving options.
* Code Generation:
jOOQ generates a simple Java representation of your database schema. Every table, view, stored procedure, enum, UDT is a class.
So far, there had been only few database abstraction frameworks or libraries, that truly respected SQL as a first class citizen among languages. Most frameworks, including the industry standards JPA, EJB, Hibernate, JDO, Criteria Query, and many others try to hide SQL itself, minimising its scope to things called JPQL, HQL, JDOQL and various other inferior query languages
* Active records:
jOOQ implements an easy-to-use active record pattern. It is **not** an OR-mapper, but provides a 1:1 mapping between tables/views and classes. Between columns and members.
jOOQ has come to fill this gap.
* Typesafe SQL:
jOOQ allows for writing compile-time typesafe querying using its built-in DSL.
jOOQ's reason of being - compared to LINQ
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* SQL standard:
jOOQ supports all standard SQL language features including the more complex `UNION`'s, nested `SELECT`s, joins, aliasing.
Other platforms incorporate ideas such as LINQ (with LINQ-to-SQL), or Scala's SLICK, or also Java's QueryDSL to better integrate querying as a concept into their respective language. By querying, they understand querying of arbitrary targets, such as SQL, XML, Collections and other heterogeneous data stores. jOOQ claims that this is going the wrong way too.
* Vendor-specific feature support:
jOOQ encourages the use of vendor-specific extensions such as stored procedures, UDT's and ARRAY's, recursive queries, and many more.
In more advanced querying use-cases (more than simple CRUD and the occasional JOIN), people will want to profit from the expressivity of SQL. Due to the relational nature of SQL, this is quite different from what object-oriented and partially functional languages such as C#, Scala, or Java can offer.
It is very hard to formally express and validate joins and the ad-hoc table expression types they create. It gets even harder when you want support for more advanced table expressions, such as pivot tables, unnested cursors, or just arbitrary projections from derived tables. With a very strong object-oriented typing model, these features will probably stay out of scope.
In essence, the decision of creating an API that looks like SQL or one that looks like C#, Scala, Java is a definite decision in favour of one or the other platform. While it will be easier to evolve SLICK in similar ways as LINQ (or QueryDSL in the Java world), SQL feature scope that clearly communicates its underlying intent will be very hard to add, later on (e.g. how would you model Oracle's partitioned outer join syntax? How would you model ANSI/ISO SQL:1999 grouping sets? How can you support scalar subquery caching? etc...).
jOOQ has come to fill this gap.
jOOQ is different
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SQL was never meant to be abstracted. To be confined in the narrow boundaries of heavy mappers, hiding the beauty and simplicity of relational data. SQL was never meant to be object-oriented. SQL was never meant to be anything other than... SQL!
For more details please visit [jooq.org](http://www.jooq.org).