LINQ Reference for NCache

Note

This feature is only available in NCache Enterprise Edition.

NCache supports both Query and Lambda execution for LINQ. This page provides sample queries for supported operators for each execution type.

First, keep in mind that the following are not currently supported by NCache LINQ Provider:

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

The syntax will usually appear as follows:

FROM [Object] IN [List]
WHERE [Conditionn]
SELECT [Object]

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

Operator(s) Examples
select Query: from product in products select product;
Lambda: products.Select(p => p);

Restriction Operators

Operator(s) Examples
where Query: from product in products where product.ProductID == 1001 select product;
Lambda: products.Where(p => p.ProductID == 1001);

Basic Query Operators

Operator(s) Examples
== Query: from product in products where product.ProductID == 1001 select product;
Lambda: products.Select(p => p).Where(p => p.ProductID == 1001);
!= Query: from product in pproducts where product.ProductID != 1001 select product;
Lambda: products.Select(p => p).Where(p => p.ProductID != 1001);
< Query: from product in products where product.ProductID < 1001 select product;
Lambda: products.Select(p => p).Where(p => p.ProductID < 1001);
> Query: from product in products where product.ProductID > 1001 select product;
Lambda: products.Select(p => p).Where(p => p.ProductID > 1001);
<= Query: from product in products where product.ProductID <= 1001 select product;
Lambda: products.Select(p => p).Where(p => p.ProductID <= 1001);
>= Query: from product in products where product.ProductID >= 1001 select product;
Lambda: products.Select(p => p).Where(p => p.ProductID >= 1001);

Logical Operators

Operator(s) Examples
&& Query: from product in products where product.ProductID >= 1001 && product.ProductName == "Chai" select product;
Lambda: products.Select(p => p).Where(p => p.ProductID >= 1001 && p.ProductName == "Chai");
|| Query:
from product in products where product.ProductID == 1001 || product.ProductName == "Chai" select product;
Lambda: products.Select(p => p).Where(p => p.ProductID >= 1001 || p.ProductName == "Chai");

Aggregation Operators

Operator(s) Examples
Count Query: (from product in products where product.Category == "Beverages" select product).Count();
Lambda: products.Select(p => p).Where(p => p.Category == "Beverages").Count();
Max Query: (from product in products where product.Category == "Beverages" select product.ProductID).Max();
Lambda: products.Where(p => p.Category == "Beverages").Max(p => p.ProductID);
Min Query: (from product in products where product.Category == "Beverages" select product.ProductID).Min();
Lambda: products.Where(p => p.Category == "Beverages").Min(p => p.ProductID);
Average Query: (from product in products where product.ProductID < 1010 select product.ProductID).Average();
Lambda: products.Where(p => p.ProductID > 1001).Average(p => p.ProductID);
Sum Query: (from product in products where product.ProductID <= 1010 select product.ProductID).Sum();
Lambda: products.Where(p => p.ProductID > 1001).Sum(p => p.ProductID);

Wildcard Operators

Operator(s) Example
StartsWith Query: from product in products where product.Category.StartsWith("Be") select product;
Lambda: products.Select(p => p).Where(p => p.Category.StartsWith("Be"));
EndsWith Query: from product in products where product.Category.EndsWith("ages") select product;
Lambda: products.Select(p => p).Where(p => p.Category.EndsWith("ages"));
Contains Query: from product in products where product.Category.Contains("Bever") select product;
Lambda: products.Select(p => p).Where(p => p.Category.Contains("Bever"));
Equals Query: from product in products where product.Category.Equals("Beverages") select product;
Lambda: products.Select(p => p).Where(p => p.Category.Equals("Beverages"));

See Also

Query Objects with LINQ
Configure LINQPad for NCache
Event Notifications in Cache