To further manipulate data, we can also use operators, expressions, and functions in HQL to transform data. The Hive wiki (https://cwiki.apache.org/confluence/display/Hive/LanguageManual+UDF) offers specifications for all supported expressions and functions, so we do not want to repeat all of them here, except a few important tips in this chapter.
Hive has defined relational operators, arithmetic operators, logical operators, complex type operators, and complex type constructors. For relational, arithmetic, and logical operators, they are similar to standard operators in SQL/Java. For operators on a complex data type, we have already introduced them in the Understanding Hive data types Section in Chapter 3, Data Definition and Description, as well as the example of inserting data into dynamic partitions earlier in this chapter. Functions in HQL are categorized as follows...