Description

Left outer join two batch operators.

Parameters

Name Description Type Required？ Default Value
joinPredicate joinPredicate String ✓
selectClause Select clause String “*”
type Join type, one of “join”, “leftOuterJoin”, “rightOuterJoin”, “fullOuterJoin” String “join”

Script Example

Code

  1. URL = "http://alink-dataset.cn-hangzhou.oss.aliyun-inc.com/csv/iris.csv"
  2. SCHEMA_STR = "sepal_length double, sepal_width double, petal_length double, petal_width double, category string";
  3. data1 = CsvSourceBatchOp().setFilePath(URL).setSchemaStr(SCHEMA_STR)
  4. data2 = CsvSourceBatchOp().setFilePath(URL).setSchemaStr(SCHEMA_STR)
  6. joinOp = LeftOuterJoinBatchOp().setJoinPredicate("a.category=b.category").setSelectClause("a.petal_length")
  7. output = joinOp.linkFrom(data1, data2)
名称 中文名称 描述 类型 是否必须？ 默认值
joinPredicate where语句 where语句 String ✓
selectClause select语句 select语句 String “*”
type join类型 join类型: “join”, “leftOuterJoin”, “rightOuterJoin” 或 “fullOuterJoin” String “join”