| otherwise {SparkR} | R Documentation | 
If values in the specified column are null, returns the value.
Can be used in conjunction with when to specify a default value for expressions.
otherwise(x, value) ## S4 method for signature 'Column' otherwise(x, value)
| x | a Column. | 
| value | value to replace when the corresponding entry in  | 
otherwise since 1.5.0
Other column_func: 
alias(),
between(),
cast(),
endsWith(),
over(),
startsWith(),
substr()