selectExpr {SparkR} | R Documentation |
Select from a SparkDataFrame using a set of SQL expressions.
## S4 method for signature 'SparkDataFrame,character' selectExpr(x, expr, ...)
x |
A SparkDataFrame to be selected from. |
expr |
A string containing a SQL expression |
... |
Additional expressions |
A SparkDataFrame
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
, join
,
limit
, merge
,
mutate
, ncol
,
persist
, printSchema
,
registerTempTable
, rename
,
repartition
, sample
,
saveAsTable
, select
,
showDF
, show
,
str
, take
,
unionAll
, unpersist
,
withColumn
, write.df
,
write.jdbc
, write.json
,
write.parquet
, write.text
## Not run:
##D sc <- sparkR.init()
##D sqlContext <- sparkRSQL.init(sc)
##D path <- "path/to/file.json"
##D df <- read.json(sqlContext, path)
##D selectExpr(df, "col1", "(col2 * 5) as newCol")
## End(Not run)