Expressions.expr-factor

A single value

Format

[ + | - ]{ Literal |
expr-column-ref |
expr-primary-constant |
expr-primary-datetime |
expr-primary-interval |
expr-primary-cast |
( expression ) |
( query-expr ) |
expr-primary-sumfunc |
Case expression |
Numeric value function |
String value function |
expr-primary-format |
expr-primary-element |
expr-primary-opc-time |
expr-primary-odbc-function |
expr-primary-odbc-datetime }

Remarks

An expression factor can be any one of the following:

• A constant value literal, such as 12, or 'String', or X'FFFF'. Refer to Literals for more details.
• A column reference, optionally enclosed in double quotes. Refer to expr-column-ref for more details.
• A constant value keyword, such as CURRENT_TIMESTAMP, TRUE, or FALSE. Refer to expr-primary-constant for more details.
• A DATE, TIME, or TIMESTAMP constant value. Refer to expr-primary-datetime for more details.
• An INTERVAL constant value. Refer to expr-primary-interval for more details.
• A conversion from one type to another using the CAST operator. Refer to expr-primary-cast for more details.
• A nested scalar expression using parentheses to control order of evaluation.
• A scalar subquery returning exactly one value. This consists of a query-expr enclosed in parentheses. It is an error if the scalar subquery returns more than 1 row or column.
• An aggregate function, such as COUNT, SUM, AVG, MAX or MIN. Refer to expr-primary-sumfunc for more details.
• An expression returning a value based on a condition, for example CASE, NULLIF. Refer to Case expression for more details.
• A function returning a numeric value, for example SQRT, POSITION. Refer to Numeric value function for more details.
• A function returning a string value, for example SUBSTRING, REPLACE. Refer to String value function for more details.
• An ELEMENT function to return a substring from a string of delimiter separated strings. Refer to expr-primary-element for more details.
• An OPC style time or interval. Refer to expr-primary-opc-time for more details.
• An ODBC function. Refer to expr-primary-odbc-function for more details.
• A D, T, or TS constant value. Refer to expr-primary-odbc-datetime for more details.