DROP TABLE IF EXISTS test.src; DROP TABLE IF EXISTS test.dst; DROP TABLE IF EXISTS test.mv; CREATE TABLE test.src (x UInt8) ENGINE = Null; CREATE TABLE test.dst (x UInt8) ENGINE = Memory; USE test; CREATE MATERIALIZED VIEW mv TO dst AS SELECT * FROM src; INSERT INTO src VALUES (1), (2); SELECT * FROM mv ORDER BY x; -- Detach MV and see if the data is still readable DETACH TABLE mv; SELECT * FROM dst ORDER BY x; USE default; -- Reattach MV (shortcut) ATTACH TABLE test.mv; INSERT INTO test.src VALUES (3); SELECT * FROM test.mv ORDER BY x; -- Drop the MV and see if the data is still readable DROP TABLE test.mv; SELECT * FROM test.dst ORDER BY x; DROP TABLE test.src; DROP TABLE test.dst;