Number-Type Literals
Vertica supports three types of numbers: integers, numerics, and floats.
- Integers are whole numbers less than 2^63 and must be digits.
- Numerics are whole numbers larger than 2^63 or that include a decimal point with a precision and a scale. Numerics can contain exponents. Numbers that begin with 0x are hexadecimal numerics.
Numeric-type values can also be generated using casts from character strings. This is a more general syntax. See the Examples section below, as well as Data Type Coercion Operators (CAST).
Syntax
digits digits.[digits] | [digits].digits digits e[+-]digits | [digits].digits e[+-]digits | digits.[digits] e[+-]digits
Parameters
digits | One or more numeric characters, 0 through 9 |
e | Exponent marker |
Notes
- At least one digit must follow the exponent marker (
e
), ife
is present.
- There cannot be any spaces or other characters embedded in the constant.
- Leading plus (+) or minus (–) signs are not considered part of the constant; they are unary operators applied to the constant.
- In most cases a numeric-type constant is automatically coerced to the most appropriate type depending on context. When necessary, you can force a numeric value to be interpreted as a specific data type by casting it as described in Data Type Coercion Operators (CAST).
- Floating point literals are not supported. If you specifically need to specify a float, you can cast as described in Data Type Coercion Operators (CAST).
- Vertica follows the IEEE specification for floating point, including NaN (not a number) and Infinity (Inf).
- A NaN is not greater than and at the same time not less than anything, even itself. In other words, comparisons always return false whenever a NaN is involved.
- Dividing INTEGERS (x / y) yields a NUMERIC result. You can use the // operator to truncate the result to a whole number.
Examples
The following are examples of number-type literals:
42 3.5 4. .001 5e2 1.925e-3
Scientific notation:
=> SELECT NUMERIC '1e10'; ?column? ------------- 10000000000 (1 row)
BINARY
scaling:
=> SELECT NUMERIC '1p10'; ?column? ---------- 1024 (1 row) => SELECT FLOAT 'Infinity'; ?column? ---------- Infinity (1 row)
The following examples illustrated using the / and // operators to divide integers:
=> SELECT 40/25; ?column? ---------------------- 1.600000000000000000 (1 row)
=> SELECT 40//25; ?column? ---------- 1 (1 row)