Azure Digital Twins query language reference: Operators
This document contains reference information on operators for the Azure Digital Twins query language.
Comparison operators
The following operators from the comparison family are supported.
=
,!=
: Used to compare equality of expressions.<
,>
: Used for ordered comparison of expressions.<=
,>=
: Used for ordered comparison of expressions, including equality.
Example
Here's an example using =
. The following query returns twins whose Temperature value is equal to 80.
SELECT *
FROM DIGITALTWINS DT
WHERE DT.Temperature = 80
Here's an example using <
. The following query returns twins whose Temperature value is less than 80.
SELECT *
FROM DIGITALTWINS DT
WHERE DT.Temperature < 80
Here's an example using <=
. The following query returns twins whose Temperature value is less than or equal to 80.
SELECT *
FROM DIGITALTWINS DT
WHERE NOT DT.Temperature <= 80
Contains operators
The following operators from the contains family are supported.
IN
: Evaluates to true if a given value is in a set of values.NIN
: Evaluates to true if a given value isn't in a set of values.
Example
Here's an example using IN
. The following query returns twins whose owner
property is one of several options from a list.
SELECT *
FROM DIGITALTWINS DT
WHERE DT.owner IN ['John', 'Anil', 'Bailey', 'Alex']
Logical operators
The following operators from the logical family are supported:
AND
: Used to connect two expressions, evaluates to true if they're both true.OR
: Used to connect two expressions, evaluates to true if at least one of them is true.NOT
: Used to negate an expression, evaluates to true if the expression condition isn't met.
Example
Here's an example using AND
. The following query returns twins who meet both conditions of Temperature less than 80 and Humidity less than 50.
SELECT *
FROM DIGITALTWINS DT
WHERE DT.Temperature < 80 AND DT.Humidity < 50
Here's an example using OR
. The following query returns twins who meet at least one of the conditions of Temperature less than 80 and Humidity less than 50.
SELECT *
FROM DIGITALTWINS DT
WHERE DT.Temperature < 80 OR DT.Humidity < 50
Here's an example using NOT
. The following query returns twins who don't meet the conditions of Temperature less than 80.
SELECT *
FROM DIGITALTWINS DT
WHERE NOT DT.Temperature < 80
Limitations
The following limits apply to queries using operators.
See the section below for more details.
Limit for IN/NIN
The limit for the number of values that can be included in an IN
or NIN
set is 100 values.
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