ErrorToken illegal character in a query having / @ $ . symbols

[Mohamed Nadjib MAMI <ma...@iai.uni-bonn.de>]

Hello all,

Could someone please help me figure out what wrong with my query that 
I'm running over Parquet tables? the query has the following form:

weird_query = "SELECT a._example.com/aa/1.1/aa_, 
b._example.com/bb/1.2/bb_ FROM www$aa@aa a LEFT JOIN www$bb@bb b ON 
a.http://example.de/cc=b.column"

I got the exception: /"failure: ``union'' expected but 
ErrorToken(illegal character) found"/ on the position of equal symbol "="

So I tried to backtick the column names but got the same exception in 
the same position (i.e. "=" position):

weird_query = "SELECT a._`example.com/aa/1.1/aa`_, 
b._`example.com/bb/1.2/bb_` FROM www$aa@aa a LEFT JOIN www$bb@bb b ON 
a.`http://example.de/cc`=b.`column`

I tried to google the list of illegal characters on SparkSQL but didn't 
find any.

Cheers,
-- 
PhD Student - EIS Group - Bonn University, Germany.