From b0fd51fe2432a5d905220ca94918fd95cebe9e7e Mon Sep 17 00:00:00 2001 From: Claude Code Date: Wed, 29 Jul 2026 16:29:34 -0700 Subject: [PATCH] test(sql): SHOW statements must not get a forced LIMIT (#36939) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit set_limit_value's FORCE_LIMIT path unconditionally sets _parsed.args["limit"] on any statement, including SHOW TABLES/ DATABASES/CREATE TABLE. sqlglot's Show expression has no real LIMIT slot to hold that value, so it renders a malformed statement with two LIMIT keywords instead of rejecting cleanly. StarRocks (and likely other engines using FORCE_LIMIT) reject the result outright, which is exactly the "Unexpected input 'LIMIT'" error reported in #36939 for SHOW TABLES / SHOW DATABASES / SHOW CREATE TABLE. This is unrelated to the other two statements in that issue (REFRESH EXTERNAL TABLE, DROP ... FORCE) — those fail to parse at the sqlglot layer entirely, confirmed still true against the pinned sqlglot 30.12.0 for every dialect tried, not just starrocks. That's an upstream sqlglot dialect gap, not something fixable in this repo, so it's out of scope here. This is a test-only PR; the test is expected to be RED (confirms the bug, does not fix it). Not using a closing keyword since merging this alone won't resolve #36939. Co-Authored-By: Claude Sonnet 4.6 --- tests/unit_tests/sql/parse_tests.py | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/tests/unit_tests/sql/parse_tests.py b/tests/unit_tests/sql/parse_tests.py index bec1849a196..d5dc161b738 100644 --- a/tests/unit_tests/sql/parse_tests.py +++ b/tests/unit_tests/sql/parse_tests.py @@ -2243,6 +2243,34 @@ def test_set_limit_value( assert statement.format() == expected +@pytest.mark.parametrize( + "sql", + [ + "SHOW TABLES", + "SHOW DATABASES", + "SHOW CREATE TABLE test.will_test1", + ], +) +def test_set_limit_value_leaves_show_statements_unchanged(sql: str) -> None: + """ + Regression for #36939: FORCE_LIMIT must not touch ``SHOW`` statements. + + ``SHOW`` statements have no `LIMIT` clause in sqlglot's expression tree, + so forcing one via ``args["limit"]`` doesn't reject cleanly, it produces + a malformed statement with two ``LIMIT`` keywords (one from a stray + rendering of the bare ``Limit`` expression, one from the forced value). + StarRocks (and presumably other engines) reject that outright: "Getting + syntax error ... Unexpected input 'LIMIT'". The statement should be + left untouched instead, matching how ``SELECT`` statements without a + scannable row source aren't force-limited either. + """ + statement = SQLStatement(sql, "starrocks") + original = statement.format() + statement.set_limit_value(1000, LimitMethod.FORCE_LIMIT) + assert statement.format() == original + assert "LIMIT" not in statement.format() + + @pytest.mark.parametrize( "kql, limit, expected", [