Issue with column alias' that are the same as a table alias

[christopherpickering]

Hey, thanks again for the tool!

I found an issue w/ SQL SERVER sql:

SELECT
  two.col two
FROM
  dbo.table_one one
  Left JOIN dbo.table_two two ON two.id = one.id

Causes a failure

/sql_metadata/parser.py", line 724, in _add_to_columns_aliases_subsection
    section = COLUMNS_SECTIONS[keyword]
KeyError: 'LEFTJOIN'

If I change the alias on the column to something else, then we pass. But both are valid sql.. is it possible for the parser to accept this as valid?

[domecrane]

Hi, I also want to thank you for this tool. It's awesome!

Let me add some comments to this issue.

I noticed that I get the following error sometimes: AttributeError: 'NoneType' object has no attribute 'normalized'

When I was trying to test it, I found this: My goal is to receive the list of the used table names, so I use the Parser(query_alt).tables method/function. Here is an example code filled with dummy values. The mentioned method works correctly.

query_alt = '''
with main as
(
		select	 a.*,
				 b."attribute_b" as "asd"

		from	"table_a" a

		left join	"table_b" b
		on		 b."id" = a."b_id"
)
----------------------------------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------------------------------

select	 main.*,
		 other_q."attribute_e"

from	 main

left join
(
        select	 m."o_id"
        from	"main" m

        left join	"table_c" c
        on		 c."id" = m."id_c"

        where	 lower(c."attribute_d") != \'unspecified\'
        group by	 1, 2
) other_q
on		 other_q."o_id" = main."m_id"
'''

BUT if I add an altered name of a column it crashes:

query_alt = '''
with main as
(
		select	 a.*,
				 b."attribute_b" as "asd"

		from	"table_a" a

		left join	"table_b" b
		on		 b."id" = a."b_id"
)
----------------------------------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------------------------------

select	 main.*,
		 other_q."attribute_e"

from	 main

left join
(
        select	 m."o_id" as "asd2"
        from	"main" m

        left join	"table_c" c
        on		 c."id" = m."id_c"

        where	 lower(c."attribute_d") != \'unspecified\'
        group by	 1, 2
) other_q
on		 other_q."o_id" = main."m_id"
'''
Parser(query_alt).tables

If I remove the visual separator (------) between the WITH and the main select, it works again:

query_alt = '''
with main as
(
		select	 a.*,
				 b."attribute_b" as "asd"

		from	"table_a" a

		left join	"table_b" b
		on		 b."id" = a."b_id"
)

select	 main.*,
		 other_q."attribute_e"

from	 main

left join
(
        select	 m."o_id" as "asd2"
        from	"main" m

        left join	"table_c" c
        on		 c."id" = m."id_c"

        where	 lower(c."attribute_d") != \'unspecified\'
        group by	 1, 2
) other_q
on		 other_q."o_id" = main."m_id"
'''
Parser(query_alt).tables

Could you please take a look at it?

Thank you!