如果这种问题不能用sparkyr解决，我感到非常惊讶：

iris_tbl <- copy_to(sc, aDataFrame)

# date_vector is a character vector of element

# in this format: YYYY-MM-DD (year, month, day)

for (d in date_vector) {
   ...
   aDataFrame %>% mutate(newValue=gsub("-","",d)))
   ...
}

我收到这个错误：

Error: org.apache.spark.sql.AnalysisException: Undefined function: 'GSUB'. This function is neither a registered temporary function nor a permanent function registered in the database 'default'.; line 2 pos 86
    at org.apache.spark.sql.catalyst.catalog.SessionCatalog.failFunctionLookup(SessionCatalog.scala:787)
    at org.apache.spark.sql.hive.HiveSessionCatalog.lookupFunction0(HiveSessionCatalog.scala:200)
    at org.apache.spark.sql.hive.HiveSessionCatalog.lookupFunction(HiveSessionCatalog.scala:172)
    at org.apache.spark.sql.catalyst.analysis.Analyzer$ResolveFunctions$$anonfun$apply$13$$anonfun$applyOrElse$6$$anonfun$applyOrElse$39.apply(Analyzer.scala:884)
    at org.apache.spark.sql.catalyst.analysis.Analyzer$ResolveFunctions$$anonfun$apply$13$$anonfun$applyOrElse$6$$anonfun$applyOrElse$39.apply(Analyzer.scala:884)
    at org.apache.spark.sql.catalyst.analysis.package$.withPosition(package.scala:48)
    at org.apache.spark.sql.catalyst.analysis.Analyzer$ResolveFunctions$$anonfun$apply$13$$anonfun

但用这句话：

aDataFrame %>% mutate(newValue=toupper("hello"))

一切正常。有人帮忙吗？