DROP TABLE IF EXISTS test.prewhere_defaults; CREATE TABLE test.prewhere_defaults (d Date DEFAULT '2000-01-01', k UInt64 DEFAULT 0, x UInt16) ENGINE = MergeTree(d, k, 1); INSERT INTO test.prewhere_defaults (x) VALUES (1); SET max_block_size = 1; SELECT * FROM test.prewhere_defaults PREWHERE x != 0 ORDER BY x; ALTER TABLE test.prewhere_defaults ADD COLUMN y UInt16 DEFAULT x; SELECT * FROM test.prewhere_defaults PREWHERE x != 0 ORDER BY x; INSERT INTO test.prewhere_defaults (x) VALUES (2); SELECT * FROM test.prewhere_defaults PREWHERE x != 0 ORDER BY x; DROP TABLE test.prewhere_defaults;