This section describes basic syntax elements that can appear in expressions.

There are different sort of basic syntax elements such as operators for arithmetic, string and comparison, predefined variables and registers like SQLSTATE, and utility operators like SFMT() or TODAY.

Elements of an expressions are evaluated by following precedence rules, from highest to lowest, as described in the order of precedence list. Use () parentheses to instruct the runtime system to evaluate the expression in a different way than the default order of precedence.