LINQ Reference for NCache

Note

This feature is only available in NCache Enterprise Edition.

NCache provides support for both Lambda execution and Query execution for LINQ. This topic provides sample examples for supported operators for each execution type.

At the moment, the following are not supported by NCache LINQ Provider:

• Nested queries
• ORDER BY operator
• GROUP BY operator
• JOIN operator

The following examples assume a Product class object which contains ProductID, ProductName and Category attributes.

Note that the examples in Query expressions are alternative to Lambda expression queries, and vice versa.

Projection Operators

Lambda Expression

Operator(s)	Examples
Select	products.Select(p => p).Where(p => p.ProductID == 1001);

Query Expression

Operator(s)	Examples
select	from product in products select product;

Restriction Operators

Lambda Expression

Operator(s)	Examples
Where	products.Where(p => p.ProductID == 1001);

Query Expression

Operator(s)	Examples
where	from product in products where product.ProductID == 1001 select product;

Basic Query Operators

Lambda Expressions

Operator(s)	Examples
==	products.Select(p => p).Where(p => p.ProductID == 1001);
!=	products.Select(p => p).Where(p => p.ProductID != 1001);
<	products.Select(p => p).Where(p => p.ProductID < 1001);
>	products.Select(p => p).Where(p => p.ProductID > 1001);
<=	products.Select(p => p).Where(p => p.ProductID <= 1001);
>=	products.Select(p => p).Where(p => p.ProductID >= 1001);

Query Expressions

Operator(s)	Examples
==	from product in products where product.ProductID == 1001 select product;
<	from product in products where product.ProductID < 1001 select product;
>	from product in products where product.ProductID > 1001 select product;
<=	from product in products where product.ProductID <= 1001 select product;
>=	from product in products where product.ProductID >= 1001 select product;

Logical Operators

Lambda Expressions

Operator(s)	Examples
&&	products.Select(p => p).Where(p => p.ProductID >= 1001 && p.ProductName == "Chai");
||	products.Select(p => p).Where(p => p.ProductID >= 1001 || p.ProductName == "Chai");

Query Expressions

Operator(s)	Examples
&&	from product in products where product.ProductID >= 1001 && product.ProductName == "Chai" select product;
||	from product in products where product.ProductID == 1001 || product.ProductName == "Chai" select product;

Aggregation Operators

Lambda Expressions

Operator(s)	Examples
Count	products.Select(p => p).Where(p => p.Category == "Beverages").Count();
Max	products.Where(p => p.Category == "Beverages").Max(p => p.ProductID);
Min	products.Where(p => p.Category == "Beverages").Min(p => p.ProductID);
Average	products.Where(p => p.ProductID > 1001).Average(p => p.ProductID);
Sum	products.Where(p => p.ProductID > 1001).Sum(p => p.ProductID);

Query Expressions

Operator(s)	Examples
Count	(from product in products where product.Category == "Beverages" select product).Count();
Max	(from product in products where product.Category == "Beverages" select product.ProductID).Max();
Min	(from product in products where product.Category == "Beverages" select product.ProductID).Min();
Average	(from product in products where product.ProductID < 1010 select product.ProductID).Average();
Sum	(from product in products where product.ProductID <= 1010 select product.ProductID).Sum();

Wildcard Operators

Lambda Expressions

Operator(s)	Example
StartsWith	products.Select(p => p).Where(p => p.Category.StartsWith("Be"));
EndsWith	products.Select(p => p).Where(p => p.Category.EndsWith("ages"));
Contains	products.Select(p => p).Where(p => p.Category.Contains("Bever"));
Equals	products.Select(p => p).Where(p => p.Category.Equals("Beverages"));

Query Expressions

Operator(s)	Example
StartsWith	from product in products where product.Category.StartsWith("Be") select product;
EndsWith	from product in products where product.Category.EndsWith("ages") select product;
Contains	from product in products where product.Category.Contains("Bever") select product;
Equals	from product in products where product.Category.Equals("Beverages") select product;

See Also

Search Objects with LINQ
Configure LINQPad for NCache
SQL Search in Cache
Event Notifications in Cache