Slick 3.0.0 RC1 发布，Scala 数据库访问层

发布于 2015-02-24 00:54:46 | 519 次阅读 | 评论: 0 | 来源: 网友投递

这里有新鲜出炉的Scala 教程，程序狗速度看过来！

Scala 编程语言

可伸缩的语言是一种多范式的编程语言，一种类似java的编程 ，设计初衷是要集成面向对象编程和函数式编程的各种特性。Scala是在JVM上运行。

Slick 是 TypeSafe 推出的 Scala 数据库访问库。开发者可以使用 Scala 语言风格来编写数据查询，而不是用 SQL，示例代码：

object Coffees extends Table[(String, Int, Double)]("COFFEES") {
  def name = column[String]("COF_NAME", O.PrimaryKey)
  def supID = column[Int]("SUP_ID")
  def price = column[Double]("PRICE")
  def * = name ~ supID ~ price
}
Coffees.insertAll(
  ("Colombian", 101, 7.99),
  ("Colombian_Decaf", 101, 8.99),
  ("French_Roast_Decaf", 49, 9.99)
) 
val q = for {
  c <- Coffees if c.supID === 101
  // ^ comparing Rep[Int] to Rep[Int]!
} yield (c.name, c.price)
 
println(q.selectStatement)
 
q.foreach { case (n, p) => println(n + ": " + p) }

Scala Slick 3.0.0 RC1 发布，源代码现已提供在：https://github.com/slick/slick/tree/3.0.0-RC1。Scala 2.10 (推荐 2.10.4) 和 2.11 (推荐 2.11.4) 构建现已提供在 Maven Central。

Slick 3.0 主要特性：

• A new API for composing and executing database actions.

• Support for the Reactive Streams API for streaming results from the database.

• Improved configuration of database connections via Typesafe Config, including built-in support for HikariCP.

• Support for nested Option types and non-primtive Option types in the Lifted Embedding.

• Properly typed outer join operators based on the improved Option support.

• A new macro-based implementation of the Plain SQL API with optional compile-time checking and type inference for embedded SQL statements.

• Many small improvements and bug fixes in the schema code generator.

• Optional multi-line formatting and indenting of generated SQL code for more readable debug output.

更新了大部分手册；“Slick Testkit” 和 “Plain SQL Queries” 章节将会尽快更新；将会尽快提供标准 Activator 模板。

如果没有发现什么重大问题，将会在后两周发布 Slick 3.0.0 最终版本！

Slick 2.1.0 以来的完整改进列表：

• bd0c9c4 Try to prevent some spurious failures on Travis CI

• 58a1db9 Proper treatment of CHAR(1) columns in JdbcModelBuilder:

• 7f0f62f Make code generator tests usable from other slick-extensions:

• 25370cb Fix bugs detected by Slick Extensions upgrade:

• 12faf5d Upgrade to Reactive Streams 1.0.0.RC3

• 648184c Package structure and project layout refactoring:

• 9c730c0 Upgrade to Reactive Streams 1.0.0.RC2:

• 24770de Add DatabaseConfig as a higher-level configuration abstraction:

• 759cbc2 Restore #$ support in the macro-based Plain SQL interpolation:

• 62ddadc Macro-based PlainSQL API Implemented TypedStaticQuery as tsql

• d63a018 UUID regression testkit:

• 0a44b74 Update LiftedEmbedding.scala

• 5af0d9b Distinguish between BLOB and BYTEA in PostgreSQL model builder

• ec7f2aa Use TestDB for code generator tests:

• cc8d3f0 Proper support for string lengths:

• 41c717a Support fetch size in statement parameters.

• 965604c Use force-insert semantics for inserting from queries and expressions.

• 0e58e7d Deprecate the Direct Embedding

• 0ba0dd5 Remove the blocking API that was introduced in 3.0.0-M1

• 2f64c79 Rename Action to DBIO:

• 86974bd Simplify SQLBuilder and formatting/indenting:

• 20378ec Quote SqlType argument in code generator.

• b1dca21 Make ColumnOptions more modular:

• 7272180 Use unconstrained text type as default on PostgreSQL

• 6cec3f7 Prefer prepareStatement(sql) instead of prepareStatement(sql, Int, Int)

• a3eec4f Support transaction isolation levels

• 6ea7fdb Generic fusion implementation for FlatMapAction and CleanupAction:

• 706f2b1 Allow the SQL statements to be overridden in SqlActions.

• a325f5e Run a user-defined init function on all created JDBC Statements

• 3315a3b Refactoring of ActionContext:

• dc687de Avoid long nested sequences of SchemaDescription.++ in generated code:

• 62d5e92 Quote illegal identifiers in generated Scala sources.

• 58c4ed5 Make ‘desiredColumnOrder’ in code generator non-final.

• a645205 Support statement parameters in the new Action-based API.

• b1c5b66 Switch JDBC metadata API and code generator to the new API.

• c92a615 Fix typo in orm-to-slick.rst

• d4f019f Move profile-level Action definitions outside of profiles.

• 5cd423f Deprecate Invoker convenience methods and iteratees

• 7d576c8 Properly deprecate .Implicit and .simple in all profile levels

• 30c135e Upgrade to sbt 0.13.7

• e9274ec Improve build system for documentation:

• a6e3b9b Further modularization of Slick:

• 4ab4a6b Switch Direct Embedding over to the new Action-based API.

• ac37f1c Update documentation for 3.0:

• e6562c7 Simplify Action Effect handling:

• 06d1ca0 Increase timeout for Reactive Streams TCK tests.

• efbe6f6 Bump version numbers:

• 4d42528 Add concurrency stress test for streaming API:

• 80929a6 Documentation plus minor improvements and fixes:

• 273b957 Update to Reactive Streams 1.0.0.M3 and fix remaining PR review issues:

• 688d7f2 Convert more test cases and add missing features:

• d862e0f Optimize the streaming engine and fix some bugs:

• 9ad62a9 Implement streaming via Reactive Streams API:

• 6a85767 Convert several test cases to the new API.

• 8ef6cde Add basic transaction support for database actions.

• 09590fd Implement session pinning for database Actions:

• 66a9b41 Basic implementation of action monad and asynchronous execution engine:

• bf17772 Use HikariCP by default (instead of no connection pooling):

• 4569c52 Simplify connection pool configuration

• cc92c26 Simplify thread pool configuration:

• 423e78c Remove the option to disable auto-commit for new connections.

• e4dddcd Remove BoneCP support and drop configuration compatibility with Play.

• 812100e Add HikariCP support in addition to BoneCP.

• bb58103 Add primitives and configuration for async execution of blocking I/O

• 0ea777a Fix broken build due to merging nested options support

• 8d4a02f Ensure generated file ends with a newline character.

• 9cdf7ec Make comment format match others in file.

• ef5f9a8 Avoid indenting blank lines, to avoid trailing whitespace.

• 8225a8f Add Option-extended joins:

• 75583dc Lifted Embedding encoding of nested and multi-column Option types:

• de389a4 Remove the Column type.

• 5da96b4 Update orm-to-slick.rst

• 7a1d119 modified to use GlobalConfig.

• 777dbeb Add SimpleLiteral factory (and fix one unrelated unchecked warning)

• 82b258f Use Unicode symbols in tree and table dumps for better readability.

• f54d272 Add BoneCP support to Database.forConfig.

• 369ad73 Use application.conf for Slick settings.

• 61d032b Corrected docs to use “inSet” instead of “inSeq”

• b0b0252 Fix forceInsertAll for single argument

• 770d0a1 Update build for 2.2.0-SNAPSHOT

• cb8183d Added support for string function repeat.

• 57aa9e7 Workaround to pass Travis CI.

• 7a58f7f Try for SQL String Indentation.

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