Hive's Data Definition Language (DDL) is a subset of HQL statements that describe the Hive data structure by creating, deleting, or altering schema objects such as databases, tables, views, partitions, and buckets. Most DDL statements start with the CREATE, DROP, or ALTER keywords. The syntax of HQL DDL is very similar to SQL DDL. In the next section, we'll focus on the details of HQL DDL.
HQL uses -- before a single line of characters as comments, and it does not support multiline comments until v2.3.0. After v2.3.0, we can use bracketed single or multiline comments between /* and */.