alpaylan opened a new issue, #2804:
URL: https://github.com/apache/datafusion-sqlparser-rs/issues/2804
The parser reads the version clause before the alias and table hints, but
Display writes it after them, so the output doesn't parse:
```
Snowflake: SELECT * FROM my_table AT(OFFSET => -60*5) AS T WHERE T.flag =
'valid'
-> displays as: SELECT * FROM my_table AS T AT(OFFSET => -60 * 5) WHERE
T.flag = 'valid'
-> reparse: Expected: identifier, found: ( at Line: 1, Column: 31
MsSql: SELECT * FROM t FOR SYSTEM_TIME AS OF '2014-01-01' AS x WITH
(NOLOCK)
-> displays as: SELECT * FROM t AS x WITH (NOLOCK) FOR SYSTEM_TIME AS OF
'2014-01-01'
-> reparse: Expected: one of UPDATE or SHARE, found: SYSTEM_TIME at Line:
1, Column: 40
Databricks: SELECT * FROM events VERSION AS OF 123 AS e
-> displays as: SELECT * FROM events AS e VERSION AS OF 123
-> reparse: Expected: end of statement, found: VERSION at Line: 1, Column:
27
```
The Snowflake input is the example from
https://docs.snowflake.com/en/sql-reference/constructs/at-before. SQL Server
documents `table_or_view_name [ FOR SYSTEM_TIME <system_time> ] [ [ AS ]
table_alias ] ... [ WITH ( <table_hint> ... ) ]`
(https://learn.microsoft.com/en-us/sql/t-sql/queries/from-transact-sql), and
Databricks puts the temporal spec in `table_name`, before `table_alias`
(https://docs.databricks.com/aws/en/sql/language-manual/sql-ref-syntax-qry-select-table-reference).
BigQuery documents the opposite order, `table_name [ as_alias ] [ FOR
SYSTEM_TIME AS OF ... ]`
(https://cloud.google.com/bigquery/docs/reference/standard-sql/query-syntax#from_clause),
and with BigQueryDialect `SELECT * FROM t AS x FOR SYSTEM_TIME AS OF
'2020-01-01'` is rejected (`Expected: one of UPDATE or SHARE, found:
SYSTEM_TIME`), while the other order parses and displays as the rejected form.
So the right position seems to be dialect dependent.
Parser: `maybe_parse_table_version` runs before `maybe_parse_table_alias` in
`parse_table_factor`. Display: the `TableFactor::Table` arm writes alias, index
hints, `WITH (...)`, then the version. The open PR #2486 mentions this in
passing and leaves it for a separate change.
Tested on main ce12f1f6 (also 0.63.0; on 0.58.0 the Databricks input is a
parse error).
Found with a property-based fuzzer (round trip check); I used AI assistance
for triage and verified every case above.
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