Chapter 3. Overview of SQL PL Language Elements

In this chapter, you will learn

• DB2 data types and the range of their values

• How to work with large objects

• How to choose proper data types

• How to work with user-defined data types (UDTs)

• How to manipulate date, time, and string data

• How to use generated columns

• How to work with SEQUENCE objects and IDENTITY columns

Now that you have learned the basic DB2 SQL procedure structure, it is time for an overview of the DB2 SQL PL language elements and their usage before discussing any of the more advanced features of the language. Many decisions on the topics covered in this chaptersuch as the choices of the proper data types and the usages of SEQUENCE objects, IDENTITY columns, and generated columnsare generally the tasks performed during database setup and table creation. Choices of the data types for parameters and local variables in the SQL procedures, User-Defined Functions (UDFs) and triggers, which are covered extensively in the rest of the book, mostly need to match the column definition in your underlying tables.