ALTER VIEW .. COMMENT

alterView("v").comment("new comment")

-- AURORA_POSTGRES, FIREBIRD, POSTGRES, TERADATA, TRINO, VERTICA, YUGABYTEDB
COMMENT ON VIEW v IS 'new comment'

-- BIGQUERY
ALTER VIEW v SET OPTIONS (DESCRIPTION = 'new comment')

-- DB2, H2, HSQLDB, ORACLE
COMMENT ON TABLE v IS 'new comment'

-- SNOWFLAKE
ALTER VIEW v SET COMMENT = 'new comment'

-- SQLSERVER
BEGIN TRY
  DECLARE @u varchar(max) = schema_name();
  EXEC sp_addextendedproperty 'MS_Description', 'new comment', 'schema', @u, 'view', 'v', DEFAULT, DEFAULT
END TRY
BEGIN CATCH
  EXEC sp_updateextendedproperty 'MS_Description', 'new comment', 'schema', @u, 'view', 'v', DEFAULT, DEFAULT
END CATCH

-- ACCESS, ASE, AURORA_MYSQL, COCKROACHDB, DERBY, DUCKDB, EXASOL, HANA, INFORMIX, MARIADB, MEMSQL, MYSQL, REDSHIFT, 
-- SQLDATAWAREHOUSE, SQLITE, SYBASE
/* UNSUPPORTED */