HistoryThe precedence of operators in an SQL statement is sometimes specified explicitly by the SQL Standard. Where this is the case, you'll find a note to that effect in our description of the operator in question. It is also possible to force a specific expression evaluation order by using parentheses in your SQL statements. Where the precedence of an SQL statement's operators is pre-determined (either by the Standard or by parentheses), those operators are effectively performed in the order specified by that precedence. Often, the Standard is silent on the subject of precedence. In cases where the precedence of operators in an SQL statement is not specifically determined either by the rules stated in the Standard, or by parentheses within the SQL statement, evaluation of expressions is effectively performed from left to right.
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