[abdolence]

SELECT * FROM t TABLESAMPLE RESERVOIR (100 ROWS) fails with Expected: end of statement, found: (.

GoogleSQL has RESERVOIR beside BERNOULLI as a TABLESAMPLE method that samples a fixed number of rows. Spanner runs it (docs). This adds the RESERVOIR keyword and TableSampleMethod::Reservoir. Like the other methods, it is not gated on a dialect.

• RESERVOIR is not reserved, so reservoir still works as a column name and as a table alias;
• BigQuery accepts any method name when parsing, then runs only SYSTEM;
• PARTITION BY inside the parentheses and WITH WEIGHT from the same grammar are not covered here.

Dialects: BigQuery

[LucaCappelletti94]

Please add a documentation link here

[abdolence]

Thanks, added a link to the docs and short description.