ClickHouse/tests/queries/0_stateless/02812_large_varints.sql

-- 64-bit integers with MSB set (i.e. values > (1ULL<<63) - 1) could for historical/compat reasons not be serialized as var-ints (issue #51486).
-- These two queries internally produce such big values, run them to be sure no bad things happen.
SELECT topKWeightedState(65535)(now(), -2) FORMAT Null;
SELECT number FROM numbers(toUInt64(-1)) limit 10 Format Null;
Allow var-int encoded 64-bit integers with MSB=1 Resolves: #51486 Until now, it was illegal to encode 64-bit (unsigned) integers with MSB=1, i.e. values > (1ULL<<63) - 1, as var-int. In more detail, the var-int code used by ClickHouse server and client spent at most 9 bytes per value such that 9 * 7 = 63 bits could be encoded. Some 3rd party clients (e.g. Rust clickhouse-rs) had the same limitation, whereas other clients understand the full range (Python clickhouse-driver). PRs #47608 and #48628 added sanity checks as asserts or exceptions during var-int encoding on the server side. This was considered okay as such huge integers so far occurred only during testing (usually fuzzing) but not in practice. Issue #51486 is a new fuzzing issue where the exception thrown from the sanity check led to a half-baked progress packet and as a result, a logical error / server crash. The only fix which is not another bandaid is to allow the full range in var-int coding. Clients will have to allow the full range too, a note will be added to the changelog. (the alternative was to create another protocol version but as var-int is used all over the place this was considered infeasible) Review note: this is the relevant commit. 2023-07-06 14:56:05 +00:00			`-- 64-bit integers with MSB set (i.e. values > (1ULL<<63) - 1) could for historical/compat reasons not be serialized as var-ints (issue #51486).`
			`-- These two queries internally produce such big values, run them to be sure no bad things happen.`
			`SELECT topKWeightedState(65535)(now(), -2) FORMAT Null;`
			`SELECT number FROM numbers(toUInt64(-1)) limit 10 Format Null;`