Neoview SQL Reference Manual (R2.2)

Expressions
An SQL value expression, referred to as an expression, can evaluate to a value with one of these
:
Operands can be combined with the concatenation
operator (||). Example: 'HOUSTON,' ||' TEXAS'
“Character Value Expressions” (page 208)
Operands can be combined in specific ways with
arithmetic operators. Example: CURRENT_DATE +
INTERVAL '1' DAY
“Datetime Value Expressions” (page 210)
Operands can be combined in specific ways with addition
and subtraction operators. Example: INTERVAL '2'
YEAR - INTERVAL '3' MONTH
“Interval Value Expressions” (page 213)
Operands can be combined in specific ways with
arithmetic operators. Example: SALARY * 1.10
“Numeric Value Expressions” (page 217)
The data type of an expression is the data type of the value of the expression.
A value expression can be, among other things, a character string literal, a numeric literal, a
dynamic parameter, or a column name that specifies the value of the column in a row of a table.
A value expression can also include, among other operands, functions and scalar subqueries.
Character Value Expressions
The operands of a character value expression—referred to as character primaries—can be
combined with the concatenation operator (||). The data type of a character primary is character
string.
character-expression is:
character-primary
| character-expression || character-primary
character-primary is:
character-string-literal
| column-reference
| character-type-host-variable
| dynamic parameter
| character-value-function
| aggregate-function
| sequence-function
| scalar-subquery
| CASE-expression
| CAST-expression
| (character-expression)
Character (or string) value expressions are built from operands that can be:
• Character string literals
• Character string functions
• Column references with character values
• Dynamic parameters
• Aggregate functions, sequence functions, scalar subqueries, CASE expressions, or CAST
expressions that return character values
Examples of Character Value Expressions
These are examples of character value expressions:
DescriptionExpression
Character string literal.
'ABILENE'
208 SQL Language Elements