8 4.1.1. Identifiers and Key Words
11 4.1.4. Special Characters
13 4.1.6. Operator Precedence
15 4.2. Value Expressions
17 4.2.1. Column References
18 4.2.2. Positional Parameters
20 4.2.4. Field Selection
21 4.2.5. Operator Invocations
23 4.2.7. Aggregate Expressions
24 4.2.8. Window Function Calls
26 4.2.10. Collation Expressions
27 4.2.11. Scalar Subqueries
28 4.2.12. Array Constructors
29 4.2.13. Row Constructors
30 4.2.14. Expression Evaluation Rules
32 4.3. Calling Functions
34 4.3.1. Using Positional Notation
35 4.3.2. Using Named Notation
36 4.3.3. Using Mixed Notation
38 This chapter describes the syntax of SQL. It forms the foundation for
39 understanding the following chapters which will go into detail about
40 how SQL commands are applied to define and modify data.
42 We also advise users who are already familiar with SQL to read this
43 chapter carefully because it contains several rules and concepts that
44 are implemented inconsistently among SQL databases or that are specific