catrix
Catrix是一个使用Scala语言封装的的,基于cassandra-driver-core实现的Cassandra数据库访问库。 期实现方式参考了Slick,使用Catrix你可以像使用Scala collections那样访问Cassandra,而不需要写Cql。 另外,通过定义Table,你还可以直接通过Table生成对应的建表Cql语句,提升开发效率。 当然,Cassandra建模和查询非常复杂,在用于真实的产品中,还是需要你对Cassandra数据库和Cql及相关性能优化有深入的了解。
#依赖配置 SBT文件:
scalaVersion := "2.11.8"
libraryDependencies++= Seq(
"com.github.wagzhi" %% "catrix" % "0.0.2-SNAPSHOT"
)
resolvers ++= Seq(
"sonatype-oss-snapshot" at "https://oss.sonatype.org/content/repositories/snapshots/",
"sonatype-oss-releases" at "https://oss.sonatype.org/content/repositories/"
)
定义表和访问接口
case class Coffee(name:String, prices:Int)
class Coffees(implicit conn:Connection) extends Table[Coffee]("coffee") {
val name = column[String]("name")
val price = column[Int]("price").index
val primaryKey = partitionKeys(name).clusteringKeys(price).orderBy(price Asc)
val parser = (name ~ parser) <> (Coffee.tupled , Coffee.unapply)
def save(coffee:Coffee)=
insert(coffee).execute
def getByName(name:String):ResultPage[Coffee] =
select(*).filter(this.name == name).execute.resultPage
//if pagingState is empty string, get first page and next pagingState included in result
def getPage(pagingState:String,pageSize:Int) =
select(*).page(pagingState,pageSize).execute.resultPage
}
获取表结构,或直接生成表
implicit val conn = Catrix.connect("127.0.0.1","keyspace_name")
val coffees = new Coffees
//打印建表语句,包括索引
coffees.createCqls.foreach(println)
//删除表,dropCql语句包含if exits
conn.session.execute(new SimpleStatement(table.dropCql))
//新建表
coffees.createCqls.
map(_=>new SimpleStatement(table,_)).
foreach(conn.session.execute)
使用表接口访问数据
implicit val conn = Catrix.connect("127.0.0.1","keyspace_name")
val coffees = new Coffees
val coffee = new Coffees("Blue Mountain Coffee","97")
coffees.save(coffee)
val coffeePage = coffees.getPage("",20)
coffeePage.results.foreach(pringln)
val nextPage = coffees.getPage(coffeePage.pagingState,20)