An issue with nested Joins

[shwetabhsharma]

Hello all,
I was trying to use sqlglot to get a list of Columns and Tables in the SQL. When a nested Join is seen, the tool complains about "Invalid Expression / Unexpected token". I was able to go past it, and see correct results by commenting out the "raiser error" in parser. However, I am certain this is not the correct way. Anyone seen this behavior? Here is some more details about the specific issue:

Table A
INNER JOIN Table B
INNER JOIN Table C
ON B.Col1 = C.Col1
INNER JOIN TABLE D
ON C.Col1 = D.Col1
INNER JOIN TABLE E
ON A.Col1 = E.Col1

So basically, INNER Join references the table but joins on it after other Joins have happened. Removing the last line for join also resolves the issue, but again that is just to point out the issue and is not a solution.

[georgesittas]

Can you post the exact query you're trying to parse and include the stack trace & the error you're getting? Make sure to include the parse_one call and all related arguments so it's easier to debug.

[tobymao]

you have a syntax error, two ONS

INNER JOIN "AINS00"."VSAG_INST_SVC" "VSAG_INST_SVC"
ON "VSAG_RK_AGR4"."SAG_ID" = "VSAG_INST_SVC"."SAG_ID"
ON "VSAG_RK_AGR4"."PLN_SGMNT_CD" = "VAVT_PLN_SGMNT"."PLN_SGMNT_CD"```

[shwetabhsharma]

That is valid and not a syntax error, and how Nested joins behave. The SQL returns data when sent to the database.
The last ON is for the first "LEFT OUTER JOIN".

[tobymao]

what dialect is this? please link the documentation

[tobymao]

it looks like tsql supports this, but it seems very uncommon and antiquated syntax, i don't think we will have any plans to implement this.

[shwetabhsharma]

Thanks @tobymao for your time.