ClickHouse/tests/queries/0_stateless/02346_position_countsubstrings_zero_byte.reference

6
6
6
6
6
6
7
7
7
7
7
7
Fix countSubstrings() & position() on patterns with 0-bytes SQL functions countSubstrings(), countSubstringsCaseInsensitive(), countSubstringsUTF8(), position(), positionCaseInsensitive(), positionUTF8() with non-const pattern argument use fallback sorters LibCASCIICaseSensitiveStringSearcher and LibCASCIICaseInsensitiveStringSearcher which call ::strstr(), resp. ::strcasestr(). These functions assume that the haystack is 0-terminated and they even document that. However, the callers did not check if the haystack contains 0-byte (perhaps because its sort of expensive). As a consequence, if the haystack contained a zero byte in it's payload, matches behind this zero byte were ignored. create table t (id UInt32, pattern String) engine = MergeTree() order by id; insert into t values (1, 'x'); select countSubstrings('aaaxxxaa\0xxx', pattern) from t; We returned 3 before this commit, now we return 6 2022-06-29 15:08:16 +00:00			`6`
			`6`
			`6`
			`6`
			`6`
			`6`
			`7`
			`7`
			`7`
			`7`
			`7`
			`7`