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Table version clause (AT(...), FOR SYSTEM_TIME AS OF, VERSION AS OF) is displayed after the alias and doesn't reparse #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
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 ce12f1f (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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