ppl-fillnull-command.md

fillnull syntax proposal

1. Proposed syntax changes with null replacement with the same values in various fields

   • ... | fillnull with 0 in field1
   • ... | fillnull with 'N/A' in field1, field2, field3
   • ... | fillnull with 2*pi() + field1 in field2
   • ... | fillnull with concat(field1, field2) in field3, field4
   • ... | fillnull with 'N/A'
     • incorrect syntax
   • ... | fillnull with 'N/A' in
     • validation error related to missing columns

2. Proposed syntax changes with null replacement with the various values in various fields

• currently implemented, not conform to previous syntax proposal (fields addition)
  • ... | fillnull fields status_code=101
  • ... | fillnull fields request_path='/not_found', timestamp='*'
• New syntax proposal
  • ... | fillnull using field1=101
  • ... | fillnull using field1=concat(field2, field3), field4=2*pi()*field5
  • ... | fillnull using field1=concat(field2, field3), field4=2*pi()*field5, field6 = 'N/A'
  • ... | fillnull using
    • validation error related to missing columns

New syntax definition in ANTLR

  
fillnullCommand
   : FILLNULL (fillNullWithTheSameValue
   | fillNullWithFieldVariousValues)
   ;

 fillNullWithTheSameValue
 : WITH nullReplacement IN nullableField (COMMA nullableField)*
 ;

 fillNullWithFieldVariousValues
 : USING nullableField EQUAL nullReplacement (COMMA nullableField EQUAL nullReplacement)*
 ;


   nullableField
   : fieldExpression
   ;

   nullReplacement
   : expression
   ;