flink 聚合函数代码研究

小咪咪 2023-01-17 09:25 227阅读 0赞

1、lag的FIX的代码： LeadLagAggFunction. 可以写sql测试代码。

/flink-table/flink-table-planner-blink/src/test/scala/org/apache/flink/table/planner/runtime/stream/sql/OverWindowITCase.scala

@Test
      def testProcTimeBoundedPartitionedRowsOver2(): Unit = {
        val t = failingDataSource(TestData.tupleData5)
            .toTable(tEnv, 'a, 'b, 'c, 'd, 'e, 'proctime.proctime)
        tEnv.registerTable("MyTable", t)
    
        val sqlQuery =  "SELECT a, b, lead(b, 2, 3) over (partition by a order by b), lag(b, 1, 3) over (partition " +
            "by a order by b) FROM MyTable ";
    
        val sink = new TestingAppendSink
        tEnv.sqlQuery(sqlQuery).toAppendStream[Row].addSink(sink)
    
        env.execute()
        println( sink.getAppendResults.sorted)
      }

2、单元测试代码：

OverWindowITCase.scala 可以查询相关测试

@Test
      def testLagFunc(): Unit = {
        checkResult(
          "SELECT a, b, lag(b, 2, 3) over (partition by a order by b) FROM Table6",
          Seq(
            row(1, 1.1, 3.0),
            row(5, -5.9, 3.0),
            row(5, -2.8, 3.0),
            row(5, 0.7, -5.9),
            row(5, 2.71, -2.8),
            row(5, 3.9, 0.7),
            row(4, 3.14, 3.0),
            row(4, 3.14, 3.0),
            row(4, 3.15, 3.14),
            row(4, 3.16, 3.14),
            row(2, -2.4, 3.0),
            row(2, 2.5, 3.0),
            row(3, -9.77, 3.0),
            row(3, 0.0, 3.0),
            row(3, 0.08, -9.77)))
    
        checkResult(
          "SELECT a, b, lag(b, -2, 3) over (partition by a order by b) FROM Table6",
          Seq(
            row(1, 1.1, 3.0),
            row(5, -5.9, 0.7),
            row(5, -2.8, 2.71),
            row(5, 0.7, 3.9),
            row(5, 2.71, 3.0),
            row(5, 3.9, 3.0),
            row(4, 3.14, 3.15),
            row(4, 3.14, 3.16),
            row(4, 3.15, 3.0),
            row(4, 3.16, 3.0),
            row(2, -2.4, 3.0),
            row(2, 2.5, 3.0),
            row(3, -9.77, 0.08),
            row(3, 0.0, 3.0),
            row(3, 0.08, 3.0)))
    
        checkResult(
          "SELECT a, b, lag(b, -2, b) over (partition by a order by b) FROM Table6",
          Seq(
            row(1, 1.1, 1.1),
            row(5, -5.9, 0.7),
            row(5, -2.8, 2.71),
            row(5, 0.7, 3.9),
            row(5, 2.71, 2.71),
            row(5, 3.9, 3.9),
            row(4, 3.14, 3.15),
            row(4, 3.14, 3.16),
            row(4, 3.15, 3.15),
            row(4, 3.16, 3.16),
            row(2, -2.4, -2.4),
            row(2, 2.5, 2.5),
            row(3, -9.77, 0.08),
            row(3, 0.0, 0.0),
            row(3, 0.08, 0.08)))
    
        checkResult(
          "SELECT a, b, lag(b, a, 3) over (partition by a order by b) FROM Table6",
          Seq(
            row(1, 1.1, 3.0),
            row(5, -5.9, 3.0),
            row(5, -2.8, 3.0),
            row(5, 0.7, 3.0),
            row(5, 2.71, 3.0),
            row(5, 3.9, 3.0),
            row(4, 3.14, 3.0),
            row(4, 3.14, 3.0),
            row(4, 3.15, 3.0),
            row(4, 3.16, 3.0),
            row(2, -2.4, 3.0),
            row(2, 2.5, 3.0),
            row(3, -9.77, 3.0),
            row(3, 0.0, 3.0),
            row(3, 0.08, 3.0)))
    
        checkResult(
          "SELECT a-1, b, lag(b, a-1, 3) over (partition by a order by b) FROM Table6",
          Seq(
            row(0, 1.1, 1.1),
            row(4, -5.9, 3.0),
            row(4, -2.8, 3.0),
            row(4, 0.7, 3.0),
            row(4, 2.71, 3.0),
            row(4, 3.9, -5.9),
            row(3, 3.14, 3.0),
            row(3, 3.14, 3.0),
            row(3, 3.15, 3.0),
            row(3, 3.16, 3.14),
            row(1, -2.4, 3.0),
            row(1, 2.5, -2.4),
            row(2, -9.77, 3.0),
            row(2, 0.0, 3.0),
            row(2, 0.08, -9.77)))
      }