DROP TABLE IF EXISTS test_lc_query CREATE TABLE test_lc_query (x UInt64, lc LowCardinality(Nullable(String))) ENGINE = MergeTree order by x INSERT INTO test_lc_query SELECT number, toString(number % 100) FROM numbers(1e7) SELECT count() FROM test_lc_query WHERE lc = '12' OR lc = '34' SELECT count() FROM test_lc_query WHERE lc = '12' OR lc = '34' OR lc = '56' DROP TABLE IF EXISTS test_lc_query