$compute

The $compute query option adds computed properties to each entity in the response.

Syntax

GET /odata/Products?$compute=price mul 1.1 as taxedPrice

Multiple computed properties are comma-separated:

GET /odata/Products?$compute=concat(firstName,' ',lastName) as fullName,price mul qty as total

Each expression follows the pattern: expression as alias.

Supported expressions

String functions

Function	Example	Result
concat(a, b)	concat(first,' ',last)	Concatenation
tolower(expr)	tolower(name)	Lowercase
toupper(expr)	toupper(code)	Uppercase

Arithmetic

Operator	Example	Result
add	price add 5	Addition
sub	price sub discount	Subtraction
mul	price mul quantity	Multiplication
div	total div count	Division (returns null if divisor is 0)

Date functions

Function	Example	Result
year(prop)	year(createdAt)	Year as integer
month(prop)	month(createdAt)	Month as integer
day(prop)	day(createdAt)	Day as integer

Literals

Type	Example
String	'hello'
Integer	42
Float	3.14

Property references

Any declared property name can be used directly:

price mul 1.1 as taxed

Evaluation

Computed properties are evaluated in PHP after the row is fetched from the database, not at the SQL level. When $compute is present, the resolver skips SQL-level $select so all columns are available for computation. The engine applies response-level projection afterward.

Interaction with $select

Computed properties are always part of the response, whatever $select names. $select accepts only declared properties, so list the declared ones you want and leave the alias out:

GET /odata/Products?$compute=price mul 1.1 as taxed&$select=name

This returns name and the computed taxed property. Naming taxed in $select answers 400 with code unknown_property.