In DistSQL statement, except for keywords, the input format of other elements shall conform to the following rules.

1. The identifier represents an object in the SQL statement, including:

• database name
• column name
• index name
• resource name
• rule name

2. When keywords or special characters appear in the identifier, use the backticks (`).

Literal

• string: enclosed in single quotes (‘) or double quotes (“)
• int: it is generally a positive integer, such as 0-9;

Note: some DistSQL syntax allows negative values. In this case, a negative sign (-) can be added before the number, such as -1.