# COLLECTION (Entity SQL)

The COLLECTION keyword is only used in the definition of an inline function. Collection functions are functions that operate on a collection of values and produce a scalar output.

## Syntax

COLLECTION(type_definition)


## Arguments

type_definition
An expression that returns a collection of supported types, rows, or references.

## Example

The following sample shows how to use the COLLECTION keyword to declare a collection of decimals as an argument for an inline query function.

USING Microsoft.Samples.Entity
Function MyAvg(dues Collection(Decimal)) AS
(
Avg(select value due from dues as due where due > @price)
)
SELECT TOP(10) contactID, MyAvg(GroupPartition(order.TotalDue))