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An expression performs functions, and mathematical and/or logical operations on other primitives and field’s values to return a result; similar to expressions in a spreadsheet. You can use various functions in Calculated Field formulas. Functions operate within the context of a single event, meaning that each function takes field values from an event and produces a new Calculated Field attached to that event.

Field names

Reference fields, or columns, by prefixing their name with a dollar sign $.
$durationMs
Field names that start with a number or contain spaces must be enclosed in double quotes ".
$"1stToken"
$"Context Key Length"

Literals

"a string"      # string
`raw string`    # raw string
10              # integer
-3              # negative integer
12.02           # float
-4.82           # negative float
4e+2            # scientific E notation
4e-2            # scientific E notation
true            # boolean
false           # boolean
null            # null

Strings

String literals are enclosed in double quotes ("a string") and support interpretation. Special characters are escaped with a backslash \. Within the quotes, any character may appear except newline ("\n") and unescaped double quote ("\\") which require the use of the backslash character.

Raw strings

Raw string literals are enclosed in single back ticks (`a raw string`). Within the quotes, any character may appear except a back quote. This is useful for expression of text that use the backslash character. For example, file paths and regular expressions.

Integers and floating point numbers

Positive or negative whole numbers or floating point numbers. E notation style numbers are also supported.
10              # integer
-3              # negative integer
12.02           # float
-4.82           # negative float
1.5e2           # scientific E notation
1.5e+2          # scientific E notation
1.5e-2          # scientific E notation

Booleans

A truthy value represented with true and false false.

Null

An empty, missing value represented with null.

Operators

Calculated fields support infix arithmetic, logical, and comparison operators. Add spaces around infix operators, otherwise your expression may not evaluate how you expect. For example:
  • $column+5 returns the value of a field named column+5.
  • $column + 5 returns the sum of five and the column field’s value.

Arithmetic operators

+       sum
-       subtraction
*       multiplication
/       division
%       modulo
Sum, subtraction, multiplication, division, and modulo infix operators are supported.
Operator syntaxEquivalent function
$a + $bSUM($a, $b)
$a - $bSUB($a, $b)
$a * $bMUL($a, $b)
$a / $bDIV($a, $b)
$a % $bMOD($a, $b)

Comparison operators

=       equal
!=      not equal
<       less than
<=      less than or equal
>       greater
>=      greater than or equal
Operator syntaxEquivalent function
$a = $bEQUALS($a, $b)
$a != $bNOT(EQUALS($a, $b))
$a < $bLT($a, $b)
$a <= $bLTE($a, $b)
$a > $bGT($a, $b)
$a >= $bGTE($a, $b)

Logical operators

AND     conditional AND
OR      conditional OR
!       NOT
Infix operators for conditional AND, conditional OR, and logical NOT.
Operator syntaxEquivalent function
$a AND $bAND($a, $b)
$a OR $bOR($a, $b)
!$a (also !($a))NOT($a)

Functions

A function’s name is all-capitalized. Function arguments (if any) are enclosed in parenthesis. Field names, literal values, and other functions are valid function arguments.
SUM(1.0, 5, "2.3")

MUL(100, DIV($json_decode_ms, $total_ms))