How the SQL Statement Chapters are Organized
The syntax diagrams show the keywords and parameters that make up the statement.
Not all keywords and parameters are valid in all circumstances. Be sure to refer to the "Semantics" section of each statement and clause to learn about any restrictions on the syntax.
The "Purpose" section describes the basic uses of the statement.
The "Prerequisites" section lists privileges you must have and steps that you must take before using the statement. In addition to the prerequisites listed, most statements also require that the database be opened by your instance, unless otherwise noted.
The "Semantics" section describes the purpose of the keywords, parameters, and clauses that make up the syntax, as well as restrictions and other usage notes that may apply to them. (The conventions for keywords and parameters used in this chapter are explained in the "Preface" of this reference.)
The "Examples" section shows how to use the various clauses and parameters of the statement.