join {SparkR}R Documentation

Join

Description

Join two SparkDataFrames based on the given join expression.

Usage

## S4 method for signature 'SparkDataFrame,SparkDataFrame'
join(x, y, joinExpr = NULL,
  joinType = NULL)

Arguments

x

A SparkDataFrame

y

A SparkDataFrame

joinExpr

(Optional) The expression used to perform the join. joinExpr must be a Column expression. If joinExpr is omitted, join() will perform a Cartesian join

joinType

The type of join to perform. The following join types are available: 'inner', 'outer', 'full', 'fullouter', leftouter', 'left_outer', 'left', 'right_outer', 'rightouter', 'right', and 'leftsemi'. The default joinType is "inner".

Value

A SparkDataFrame containing the result of the join operation.

See Also

merge

Other SparkDataFrame functions: SparkDataFrame-class, [[, agg, arrange, as.data.frame, attach, cache, collect, colnames, coltypes, columns, count, dapply, describe, dim, distinct, dropDuplicates, dropna, drop, dtypes, except, explain, filter, first, group_by, head, histogram, insertInto, intersect, isLocal, limit, merge, mutate, ncol, persist, printSchema, registerTempTable, rename, repartition, sample, saveAsTable, selectExpr, select, showDF, show, str, take, unionAll, unpersist, withColumn, write.df, write.jdbc, write.json, write.parquet, write.text

Examples

## Not run: 
##D sc <- sparkR.init()
##D sqlContext <- sparkRSQL.init(sc)
##D df1 <- read.json(sqlContext, path)
##D df2 <- read.json(sqlContext, path2)
##D join(df1, df2) # Performs a Cartesian
##D join(df1, df2, df1$col1 == df2$col2) # Performs an inner join based on expression
##D join(df1, df2, df1$col1 == df2$col2, "right_outer")
## End(Not run)

[Package SparkR version 2.0.0 Index]