Flink table的scala 代码注意写法，填坑

爱被打了一巴掌 2022-01-23 10:43 206阅读 0赞

出现错误：

Error:(13, 34) could not find implicit value for evidence parameter of type org.apache.flink.api.common.typeinfo.TypeInformation\[(Int, String)\]  
    val batch = bEnv.fromElements((133,"bbb"))

是因为scala写法隐式转换的问题，本地验证 stream   batch转成table代码，注意import：

1）stream转table

package com.coder.flink.core.table_sql
    
    import org.apache.flink.streaming.api.scala._
    import org.apache.flink.table.api.TableEnvironment
    import org.apache.flink.table.api.scala._
    
    
    
    
    
    //todo 注意import导包。是个坑
    
    object Stream2Table {
      def main(args: Array[String]): Unit = {
    
    
        val env = StreamExecutionEnvironment.getExecutionEnvironment
    
    
        //todo 创建tableEnv
        val tableEnv = TableEnvironment.getTableEnvironment(env)
        val stream =  env.fromElements((192,"aa"))
    
        tableEnv.registerDataStream("myTable2", stream, 'myLong, 'myString)
    
        val tapiResult = tableEnv.scan("myTable2")
        tapiResult.printSchema()
    
      }
    }

2）batch转table：

package com.coder.flink.core.table_sql
    
    import org.apache.flink.table.api.scala._
    import org.apache.flink.api.scala._
    import org.apache.flink.table.api.TableEnvironment
    
    
    object batch2Table {
      def main(args: Array[String]): Unit = {
        val bEnv =ExecutionEnvironment.getExecutionEnvironment
        val  batchEnv = TableEnvironment.getTableEnvironment(bEnv)
        val batch = bEnv.fromElements((133,"bbb"))
        batchEnv.registerDataSet("table1",batch)
        batchEnv.registerDataSet("table2",batch,'field1,'field2)
    
        val tapiResult = batchEnv.scan("table2")
        tapiResult.printSchema()
      }
    }