Fix 25 parser errors: multiple syntax improvements#16
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kyleconroy merged 6 commits intomainfrom Dec 15, 2025
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Parser changes: - SELECT ALL syntax (SELECT ALL 'a') - FILTER clause on aggregate functions (argMax() FILTER(WHERE ...)) - DROP SETTINGS PROFILE (DROP SETTINGS PROFILE IF EXISTS ...) - CREATE NAMED COLLECTION (CREATE NAMED COLLECTION ... AS ...) - WITH column AS alias syntax (WITH number AS k SELECT k) - SHOW TABLES NOT LIKE (SHOW TABLES NOT LIKE '%') - SHOW CREATE QUOTA (SHOW CREATE QUOTA default) - LIMIT BY with second LIMIT (LIMIT 1 BY * LIMIT 1) - WITH TOTALS HAVING clause (SELECT count() WITH TOTALS HAVING x != 0) - COLLATE in column definitions (varchar(255) COLLATE binary NOT NULL) - SETTINGS with keyword assignments (SETTINGS limit=5) - TTL GROUP BY SET clause (TTL d + interval 1 second GROUP BY x SET y = max(y)) - DROP ROW POLICY ON wildcard (DROP ROW POLICY ... ON default.*) - INSERT FROM INFILE COMPRESSION (FROM INFILE '...' COMPRESSION 'gz') - FROM before SELECT syntax (FROM numbers(1) SELECT number) - Parenthesized SELECT at statement level ((SELECT 1)) - EXISTS table syntax (EXISTS db.table) - DROP TABLE FORMAT (DROP TABLE IF EXISTS t FORMAT Null) AST changes: - Added ExistsQuery type for EXISTS table_name statements Reduced parser errors from 53 to 28 (47% reduction)
- Added parse_error field to testMetadata struct
- When parse_error is true, tests skip gracefully if parsing fails
(these are tests for SQL that ClickHouse itself expects to fail)
- Marked 59 tests with clientError SYNTAX_ERROR as parse_error: true
- Reduces reported parser errors from 28 to 20
The parse_error flag is used for queries that have -- { clientError SYNTAX_ERROR }
comments, indicating they are intentionally invalid SQL per ClickHouse's own test suite.
Lexer improvements: - Add dollar-quoted string support ($$...$$) - Add hex P notation float support (0x123p4) - Fix backtick escaping (ta``ble -> ta`ble) - Skip BOM (byte order mark) characters - Allow $ in identifier names ($alias$name$) Parser improvements: - SYSTEM DROP FORMAT SCHEMA CACHE support - EXPLAIN AST options (optimize=0, etc.) - WITH scalar expression without alias (WITH 1 SELECT 1) - DROP USER with @ hostname (user@localhost) - KEY keyword as implicit alias in expressions - Complex UNION with parentheses in FROM clause Test results: 6066 passing, 758 skipped, 0 failing Down from 20 parser errors to 7 remaining.
…ovements - Add CARET (^) handling in qualified identifiers for JSON path notation - Support parenthesized ALTER mutations: (DELETE WHERE ...), (UPDATE ...) - Add DELETE WHERE and UPDATE mutations to ALTER TABLE parsing - Support MODIFY SETTING (singular) in addition to SETTINGS - Fix CONSTRAINT CHECK parsing in CREATE TABLE - Allow keywords as CTE aliases (VALUES, KEY, etc.) - Fix SETTINGS value parsing to stop before AS (for CTAS) - Add TTL WHERE clause support for conditional deletion - Fix TTL GROUP BY with multiple expressions and SET clause Parser errors reduced from 19 to 4.
Add support for ClickHouse's PARALLEL WITH syntax for dropping multiple tables in parallel: DROP TABLE IF EXISTS t1 PARALLEL WITH DROP TABLE IF EXISTS t2 Parser errors now reduced from 19 to 3 (84% reduction).
- Skip inline data after FORMAT clause (e.g., FORMAT JSONEachRow {...})
- Support parentheses-optional * EXCEPT syntax (e.g., * EXCEPT col)
- Support named window reference in parentheses: OVER (w0)
All 19 parser errors are now fixed (100% reduction).
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Parser changes:
AST changes:
Reduced parser errors from 53 to 28 (47% reduction)