DROP DATABASE IF EXISTS test_00508; CREATE DATABASE test_00508; USE test_00508; CREATE TABLE src (x UInt8) ENGINE = Null; CREATE TABLE dst (x UInt8) ENGINE = Memory; CREATE MATERIALIZED VIEW mv_00508 TO dst AS SELECT * FROM src; INSERT INTO src VALUES (1), (2); SELECT * FROM mv_00508 ORDER BY x; -- Detach MV and see if the data is still readable DETACH TABLE mv_00508; SELECT * FROM dst ORDER BY x; USE default; -- Reattach MV (shortcut) ATTACH TABLE test_00508.mv_00508; INSERT INTO test_00508.src VALUES (3); SELECT * FROM test_00508.mv_00508 ORDER BY x; -- Drop the MV and see if the data is still readable DROP TABLE test_00508.mv_00508; SELECT * FROM test_00508.dst ORDER BY x; DROP TABLE test_00508.src; DROP TABLE test_00508.dst; DROP DATABASE test_00508;