Operators

The Power Query M formula language includes a set of operators that can be used in an expression. Operators are applied to operands to form symbolic expressions. For example, in the expression 1 + 2 the numbers 1 and 2 are operands and the operator is the addition operator (+).

The meaning of an operator can vary depending on the type of operand values. The language has the following operators:

Plus operator (+)

Expression	Equals
1 + 2	Numeric addition: 3
#time(12,23,0) + #duration(0,0,2,0)	Time arithmetic: #time(12,25,0)

Combination operator (&)

Function	Equals
"A" & "BC"	Text concatenation: "ABC"
{1} & {2, 3}	List concatenation: {1, 2, 3}
[ a = 1 ] & [ b = 2 ]	Record merge: [ a = 1, b = 2 ]

List of M operators

Common operators which apply to null, logical, number, time, date, datetime, datetimezone, duration, text, binary)

Operator	Description
>	Greater than
>=	Greater than or equal
<	Less than
<=	Less than or equal
=	Equal
<>	Not equal

Logical operators (In addition to Common operators)

Operator	Description
or	Conditional logical OR
and	Conditional logical AND
not	Logical NOT

Number operators (In addition to Common operators)

Operator	Description
+	Sum
-	Difference
*	Product
/	Quotient
+x	Unary plus
-x	Negation

Text operators (In addition to Common operators)

Operator	Description
&	Concatenation

List, record, table operators

Operator	Description
=	Equal
<>	Not equal
&	Concatenation

Record lookup operator

Operator	Description
[]	Access the fields of a record by name.

List indexer operator

Operator	Description
{}	Access an item in a list by its zero-based numeric index.

Type compatibility and assertion operators

Operator	Description
is	The expression x is y returns true if the type of x is compatible with y, and returns false if the type of x is not compatible with y.
as	The expression x as y asserts that the value x is compatible with y as per the is operator.

Date operators

Operator	Left Operand	Right Operand	Meaning
x + y	time	duration	Date offset by duration
x + y	duration	time	Date offset by duration
x - y	time	duration	Date offset by negated duration
x - y	time	time	Duration between dates
x & y	date	time	Merged datetime

Datetime operators

Operator	Left Operand	Right Operand	Meaning
x + y	datetime	duration	Datetime offset by duration
x + y	duration	datetime	Datetime offset by duration
x - y	datetime	duration	Datetime offset by negated duration
x - y	datetime	datetime	Duration between datetimes

Datetimezone operators

Operator	Left Operand	Right Operand	Meaning
x + y	datetimezone	duration	Datetimezone offset by duration
x + y	duration	datetimezone	Datetimezone offset by duration
x - y	datetimezone	duration	Datetimezone offset by negated duration
x - y	datetimezone	datetimezone	Duration between datetimezones

Duration operators

Operator	Left Operand	Right Operand	Meaning
x + y	datetime	duration	Datetime offset by duration
x + y	duration	datetime	Datetime offset by duration
x + y	duration	duration	Sum of durations
x - y	datetime	duration	Datetime offset by negated duration
x - y	datetime	datetime	Duration between datetimes
x - y	duration	duration	Difference of durations
x * y	duration	number	N times a duration
x * y	number	duration	N times a duration
x / y	duration	number	Fraction of a duration

Note

Not all combinations of values may be supported by an operator. Expressions that, when evaluated, encounter undefined operator conditions evaluate to errors. For more information about errors in M, go to Errors

Error example:

Function	Equals
1 + "2"	Error: adding number and text is not supported