public static Pair < String , String > splitColumnName ( String columnName ) { final int i = columnName . indexOf ( ' ' ) ; if ( i < 0 ) { return Pair . of ( columnName , null ) ; } else { return Pair . of ( columnName . substring ( 0 , i ) , columnName . substring ( i + 1 ) ) ; } }
Split a dot - style columnName into the main columnName and the subColumn name after the dot . Useful for columns that support dot notation .