-- Tags: long, no-replicated-database -- Tag no-replicated-database: Unsupported type of ALTER query SET output_format_pretty_row_numbers = 0; DROP TABLE IF EXISTS check_query_comment_column; -- Check COMMENT COLUMN and MODIFY COLUMN statements with simple engine CREATE TABLE check_query_comment_column ( first_column UInt8 DEFAULT 1 COMMENT 'comment 1', second_column UInt8 MATERIALIZED first_column COMMENT 'comment 2', third_column UInt8 ALIAS second_column COMMENT 'comment 3', fourth_column UInt8 COMMENT 'comment 4', fifth_column UInt8 ) ENGINE = TinyLog; SHOW CREATE TABLE check_query_comment_column; DESCRIBE TABLE check_query_comment_column; SELECT table, name, comment FROM system.columns WHERE table = 'check_query_comment_column' AND database = currentDatabase() FORMAT PrettyCompactNoEscapes; ALTER TABLE check_query_comment_column COMMENT COLUMN first_column 'comment 1_1', COMMENT COLUMN second_column 'comment 2_1', COMMENT COLUMN third_column 'comment 3_1', COMMENT COLUMN fourth_column 'comment 4_1', COMMENT COLUMN fifth_column 'comment 5_1'; SHOW CREATE TABLE check_query_comment_column; ALTER TABLE check_query_comment_column MODIFY COLUMN first_column COMMENT 'comment 1_2', MODIFY COLUMN second_column COMMENT 'comment 2_2', MODIFY COLUMN third_column COMMENT 'comment 3_2', MODIFY COLUMN fourth_column COMMENT 'comment 4_2', MODIFY COLUMN fifth_column COMMENT 'comment 5_2'; SELECT table, name, comment FROM system.columns WHERE table = 'check_query_comment_column' AND database = currentDatabase() FORMAT PrettyCompactNoEscapes; SHOW CREATE TABLE check_query_comment_column; DROP TABLE IF EXISTS check_query_comment_column; -- Check `ALTER TABLE table_name COMMENT COLUMN 'comment'` statement with MergeTree engine CREATE TABLE check_query_comment_column ( first_column UInt8 COMMENT 'comment 1', second_column UInt8 COMMENT 'comment 2', third_column UInt8 COMMENT 'comment 3' ) ENGINE = MergeTree() ORDER BY first_column PARTITION BY second_column SAMPLE BY first_column; SHOW CREATE TABLE check_query_comment_column; DESCRIBE TABLE check_query_comment_column; SELECT table, name, comment FROM system.columns WHERE table = 'check_query_comment_column' AND database = currentDatabase() FORMAT PrettyCompactNoEscapes; ALTER TABLE check_query_comment_column COMMENT COLUMN first_column 'comment 1_2', COMMENT COLUMN second_column 'comment 2_2', COMMENT COLUMN third_column 'comment 3_2'; SHOW CREATE TABLE check_query_comment_column; ALTER TABLE check_query_comment_column MODIFY COLUMN first_column COMMENT 'comment 1_3', MODIFY COLUMN second_column COMMENT 'comment 2_3', MODIFY COLUMN third_column COMMENT 'comment 3_3'; SHOW CREATE TABLE check_query_comment_column; ALTER TABLE check_query_comment_column MODIFY COLUMN first_column DEFAULT 1 COMMENT 'comment 1_3', MODIFY COLUMN second_column COMMENT 'comment 2_3', -- We can't change default value of partition key. MODIFY COLUMN third_column DEFAULT 1 COMMENT 'comment 3_3'; SELECT table, name, comment FROM system.columns WHERE table = 'check_query_comment_column' and database = currentDatabase() FORMAT PrettyCompactNoEscapes; DROP TABLE IF EXISTS check_query_comment_column; -- TODO: add here tests with ReplicatedMergeTree({database})