Conventions
- reference
The SQL++ syntax descriptions in the documentation use some notational conventions that you need to be familiar with.
The syntax descriptions are written using a W3C dialect of EBNF (Extended Backus-Naur Format).
| Convention | Notation | Example | Description | 
|---|---|---|---|
| Upper case | 
 | Indicates keywords in the syntax description. Delimited by quotes, to show that the keyword is required in the syntax. Note that you can enter keywords in upper or lower case. | |
| Single or double quotes | 
 | 
 | Indicate that the text between the quotes is required in the syntax. | 
| Pipe | 
 | 
 | Separates alternatives. | 
| Parentheses | 
 | 
 | Delimit alternatives, or group optional and repeated elements, where necessary. | 
| Question mark | 
 | 
 | Indicates that the element or group preceding the question mark is optional. | 
| Plus sign | 
 | 
 | Indicates that the element or group preceding the plus sign may appear one or many times. | 
| Asterisk | 
 | 
 | Indicates that the element or group preceding the asterisk may appear zero, one, or many times. | 
Syntax diagrams generated using Railroad Diagram Generator.