• Products
  • Solutions
  • Customers
  • Resources
  • Company
  • Pricing
  • Download
Try Playground
  • Client Side API Programming
  • Basic Operations - An Overview
  • Update/Insert Data
Show / Hide Table of Contents
  • Programmer's Guide
  • Setting Up Development Environment
    • .NET
      • Client API Prerequisites
      • Server-side API Prerequisites
    • Java
      • Client API Prerequisites
      • Server-side API Prerequisites
    • Python
      • Client API Prerequisites
    • Node.js
      • Client API Prerequisites
  • Client Side API Programming
    • Error Handling
    • Troubleshooting
    • Cache Keys and Data
    • How to Connect to Cache
    • Basic Operations - An Overview
      • Add Data
      • Update/Insert Data
      • Retrieve Data
      • Remove Data
    • Groups
      • Overview
      • Add/Update Data with Groups
      • Retrieve Data with Groups
      • Remove Data with Group
      • Search Group Data Using SQL
      • Delete Group Data Using SQL
    • Tags
      • Overview
      • Add/Update Data with Tags
      • Retrieve Data with Tags
      • Remove Data with Tags
      • Search Tag Data Using SQL
      • Delete Tag Data Using SQL
    • Named Tags
      • Overview
      • Add/Update Data with Named Tags
      • Remove Data with Named Tags
      • Search Data with Named Tags Using SQL
      • Delete Data with Named Tags Using SQL
    • Expirations
      • Overview
      • Absolute Expiration
      • Sliding Expiration
    • Data Dependency
      • Key Dependency
      • Multi-Cache Dependency
    • Dependency on Database
      • SQL Server
      • Oracle
      • OleDB with Polling
      • CLR Procedures in SQL Server
    • Dependency on External Source
      • File Dependency
      • Custom Dependency
      • Aggregate Dependency
    • Locks
      • Types of Locking
      • Pessimistic Locking
      • Optimistic Locking
    • SQL Query
      • Overview
      • Define Indexes Programmatically
      • Query with ExecuteReader and ExecuteScalar
      • Delete Data with ExecuteNonQuery
      • SQL Reference
    • LINQ Query
      • Overview
      • LINQ Query for Objects
      • LINQ Reference
    • Data Structures
      • Overview
      • List
      • Queue
      • Set
      • Dictionary
      • Counter
      • Invalidation Attributes
      • Searchable Attributes
      • Query on Data Structures
      • Remove from Data Structure
    • Events
      • Cache Level Events
      • Item Level Events
      • Management Level Events
    • Pub/Sub Messaging
      • Overview
      • Topics
      • Publish Messages
      • Subscribe to a Topic
      • Pub/Sub Events
    • Continuous Query
      • Overview
      • Use Continuous Query
    • Stream Processing
      • Add/Update Stream Data
      • Retrieve Stream Data
    • JSON
      • Overview
      • Use JSON Objects
      • Query JSON Data
    • Security API
      • Login with Credentials
    • Management API
    • Clear Cache
    • Error Logging
    • Location Affinity
  • Server-side API Programming
    • Loader and Refresher
      • Overview
      • Implement Loader and Refresher
      • Components of Loader/Refresher
    • Data Source Providers
      • Read-through
        • Implement Read-through
        • Use Read-through
      • Write-through
        • Implement Write-through
        • Use Write-through
        • Use Write-behind
    • Custom Dependency
      • Implement Extensible Dependency
      • Implement Bulk Extensible Dependency
      • Implement Notify Extensible Dependency
    • Bridge Conflict Resolver
    • Entry Processor
      • Overview
      • Implement Entry Processor
    • MapReduce
      • Overview
      • Implement MapReduce
      • Use MapReduce
    • MapReduce Aggregator
      • Overview
      • Implement and Use Aggregator
    • Compact Serialization
  • Client Side Features
    • ASP.NET Core Caching
      • Session Storage
        • Session Provider
        • IDistributedCache
        • Sessions Usage
        • Multi-site Session Provider
        • Session Sharing with ASP.NET
      • SignalR
        • NCache Extension for SignalR Core
      • Response Caching
        • Configure and Use
        • Configure with IDistributedCache
      • Data Caching
        • NCache API
        • IDistributedCache API
      • Data Protection Provider
        • Configure
    • Java Web App Caching
      • Web Sessions
        • Overview
        • Configure App
          • Add Maven Dependencies
          • Deploy Application
        • Multi-site Sessions
    • Node.js App Caching
      • Web Sessions
    • ASP.NET Caching Benefits and Overview
      • ASP.NET Session State Provider Properties
      • Multi-region ASP.NET Session State Provider Configuration
      • Session Sharing between ASP.NET and ASP.NET Core
      • ASP.NET SignalR Backplane
        • NCache Extension for SignalR
      • ASP.NET View State Caching
        • View State Content Optimization Configuration
        • Group View State with Sessions
        • Limit View State Caching
        • Page Level Grouping
      • ASP.NET Output Cache
        • Output Caching Provider Overview
        • Output Cache with Custom Hooks
  • .NET Third Party Integrations
    • Entity Framework (EF) Core
      • Installation
      • Configure
      • EF Core Extension Methods
        • Extension Methods
        • Cache Handle
        • Caching Options
        • Query Deferred API
      • Logging in EF Core
    • Entity Framework EF 6
      • EF Second Level Cache
      • EF Caching Resync Provider
      • EF Caching Configuration File
    • NHibernate
      • Second Level Cache
      • Query Caching
      • Synchronize Database with Cache
    • Debug NCache Providers in Visual Studio
  • Java Third Party Integrations
    • Hibernate
      • Second Level Cache
      • Configure Cacheable Objects and Regions
      • Configure Application
      • Query Caching
    • Spring
      • Overview
      • Use NCache with Spring
        • Configure Generic Provider
        • Configure JCache Spring Caching Provider
        • Configure Caching Declaration
        • Configure Spring Sessions
    • JCache API
      • CRUD Operations
      • Expiration
      • Events
  • Third-Party Wrappers
    • AppFabric to NCache Migration
      • AppFabric API vs. NCache API
      • Configuration Differences Between AppFabric and NCache
      • Migrating from an AppFabric Application to NCache
    • Redis to NCache Migration
      • Redis to NCache Migration
    • Memcached Wrapper
      • Memcached Gateway Approach
      • Memcached Client Plugin for .NET

Update/Insert Existing Data in Cache

NCache provides the Insert method and its overloads to facilitate updating objects in the cache. While it overwrites data for existing items, it also adds the item to the cache if the key does not exist in the cache.

Prerequisites

  • .NET
  • Java
  • Python
  • Node.js
  • Legacy API
  • To learn about the standard prerequisites required to work with all NCache client-side features, please refer to the given page on Client-Side API Prerequisites.
  • For API details, refer to: ICache, CacheItemVersion, CacheItem, Insert, Get, InsertBulk, InsertAsync.
  • To learn about the standard prerequisites required to work with all NCache client-side features, please refer to the given page on Client-Side API Prerequisites.
  • For API details, refer to: Cache, CacheItemVersion, CacheItem, get, insert, insertBulk, insertAsync.
  • To learn about the standard prerequisites required to work with all NCache client-side features, please refer to the given page on Client-Side API Prerequisites.
  • For API details, refer to: Cache, CacheItem, CacheItemVersion, insert, insert_bulk, insert_async, get.
  • To learn about the standard prerequisites required to work with all NCache client-side features, please refer to the given page on Client-Side API Prerequisites.
  • For API details, refer to: Cache, CacheItemVersion, CacheItem, get, insert, insertBulk.
  • Create a new Console Application.
  • Make sure that the data being added is serializable.
  • Add NCache References by locating %NCHOME%\NCache\bin\assembly\4.0 and adding Alachisoft.NCache.Web and Alachisoft.NCache.Runtime as appropriate.
  • Include the Alachisoft.NCache.Web.Caching namespace in your application.

Update Object in Cache

Note

This feature is also available in NCache Professional.

You can update a custom object in the cache using various overloads of the Insert method. This returns a CacheItemVersion.

Important
  • If the key already exists, it will overwrite the existing cache item with the same key.
  • If the key does not exist, the operation adds the item to the cache instead.
Note

To ensure the operation is fail-safe, it is recommended to handle any potential exceptions within your application, as explained in Handling Failures.

The following example gets the values of an existing object and inserts it against the same key into the cache. If the key does not exist, it adds it to the cache.

  • .NET
  • Java
  • Python
  • Node.js
  • Legacy API
// Precondition: Cache is already connected

string customerKey = "ALFKI";

// Get updated product from database against given product ID
Customer customer = FetchProductFromDB("ALFKI");

// Insert Product object to cache
CacheItemVersion version = cache.Insert(customerKey, customer);

// Item updated in cache successfully
// Precondition: Cache is already connected

// Get updated product from database against given product ID
Product product = fetchProductFromDB(1001);

// Insert Product object to cache
CacheItemVersion version = cache.insert("1001", product);

// Item updated in cache successfully
 
# Precondition: Cache is already connected

# Get product from database against given product ID
product = fetch_product_from_db()

# Generate a unique cache key for this product
key = "Product:" + product.get_product_id()

# Insert Product object to cache
version = cache.insert(key, product)

# Item inserted in cache successfully
// Precondition: Cache is already connected

// Get product from database against given product ID
product = await this.fetchProductFromDB();

// Generate a unique cache key for this product
var key = "Product:" + product.getProductID();

// insert Product object to cache
var version = await this.cache.insert(key, product);

// Item added in cache successfully
Product product = new Product();
product.ProductID = 1001;
product.ProductName = "Chai";
product.UnitsInStock = 5; // updated units
string key = "Product:" + product.ProductID;
//precondition: Cache is already initialized and item exists
cache.Insert(key, product);

Update Object With Expiration

Note

This feature is also available in NCache Professional.

CacheItem is a custom class provided by NCache that can be used to add data to the cache and also lets you set additional specifications associated with an object as properties of this class. The CacheItem is updated in the cache against a unique key.

Important
  • If the key already exists, it will overwrite the existing cache item with the same key.
  • If the key does not exist, the operation adds the item to the cache instead.

The following example gets updated values of an existing CacheItem and inserts it against the same key into the cache. If the key does not exist, it adds it to the cache.

  • .NET
  • Java
  • Python
  • Node.js
  • Legacy API
string customerKey = $"Customer:ALFKI";
Customer customer = FetchCustomerFromDB("ALFKI");

// Update Customer's Phone
customer.Phone = "0921-12 34 65";

// Create CacheItem
CacheItem cacheItem = new CacheItem(customer);
cacheItem.Expiration = new Expiration(ExpirationType.Sliding, TimeSpan.FromMinutes(5));

// Update cutsomer in DB and Cache
if (UpdateDB(customer))
{
    cache.Insert(customerKey, cacheItem);
}
String customerKey = "ALFKI";

// Get the customer from the database
Customer customer = fetchCustomerFromDB(customerKey);

// Update Customer's Phone
customer.setPhone("0921-12 34 65");

// Create CacheItem
CacheItem cacheItem = new CacheItem(customer);
cacheItem.setExpiration(new Expiration(ExpirationType.Sliding, TimeSpan.FromMinutes(5)));

// Update customer in DB and Cache
cache.insert(customerKey, cacheItem);
System.out.println("Customer updated in cache successfully");
# Get product from database against given product ID
product = fetch_product_from_db()

# Generate a unique cache key for this product
key = "Product:" + product.get_product_id()

# Create a new CacheItem for this product
# You can OPTIONALLY specify multiple properties e.g.Priority, Expiration
# These properties are explained in successive chapters
cache_item = ncache.CacheItem(product)

# Insert CacheItem to cache
version = cache.insert(key, cache_item)
// Get product from database against given product ID
product = await this.fetchProductFromDB();

// Generate a unique cache key for this product
var key = "Product:" + product.getProductID();

// Create a new CacheItem for this product
// You can OPTIONALLY specify multiple properties e.g. Priority, Expiration
// These properties are explained in successive chapters
var cacheItem = new ncache.CacheItem(product);

// insert CacheItem to cache
var version = await this.cache.insert(key,cacheItem);
//updating sliding expiration of 5 min through Insert API.
cache.Insert(key, product, null, Cache.NoAbsoluteExpiration, new TimeSpan(0, 5, 0), CacheItemPriority.Default);

//updating Default Sliding expiration with configured value
cache.Add(key, product, null, Cache.NoAbsoluteExpiration, Cache.DefaultSliding, CacheItemPriority.Default);

//updating SlidingLonger expiration with configured value
cache.Add(key, product, null, Cache.NoAbsoluteExpiration, Cache.DefaultSlidingLonger, CacheItemPriority.Default);

Update Bulk Items in Cache

Note

This feature is also available in NCache Professional.

InsertBulk updates an array of Cache​Item to the cache against the corresponding key. The method returns a dictionary of all the keys that failed to update, along with the failure reason.

Important

If any keys fail to update, their reasons of failure will be returned as an IDictionary.

The following code example fetches an array of products (of Customer type) from the database. The products are then inserted to the cache as a dictionary of keys and CacheItem using InsertBulk.

  • .NET
  • Java
  • Python
  • Node.js
  • Legacy API
// Create an array of all Customer Keys
String[] keys = new String[]
{
    "Customer:ALFKI", "Customer:ANATR", "Customer:ANTON", "Customer:AROUT", "Customer:BERGS"
};

// Get items from cache
IDictionary<string, Customer> itemsFetched = cache.GetBulk<Customer>(keys);

//Create a dictionary to store updated items
IDictionary<string, CacheItem> itemsUpdated = new Dictionary<string, CacheItem>();

// Update postal codes of dictionary items
foreach (KeyValuePair<string, Customer> item in itemsFetched)
{
    //Update Postal Code
    item.Value.PostalCode = "05023";

    // Create CacheItem of updated Customer object
    CacheItem updatedCacheItem = new CacheItem(item.Value);

    // Add uCacheItem to dictionary
    itemsUpdated.Add(item.Key,updatedCacheItem);
}

if (UpdateDB(itemsUpdated))
{
    // Insert updated bulk items to Cache
    IDictionary<string, Exception> keysFailedToInsert = cache.InsertBulk(itemsUpdated);

    if (keysFailedToInsert.Count > 0)
    {
        foreach (KeyValuePair<string, Exception> keyFailedToInsert in keysFailedToInsert)
            Console.WriteLine($"Could not update Item {keyFailedToInsert.Key} in cache due to error : {keyFailedToInsert.Value}");
    }
}
// Create an array of all Customer Keys
List<String> keys = List.of(
        "Customer:ALFKI",
        "Customer:ANATR",
        "Customer:ANTON",
        "Customer:AROUT",
        "Customer:BERGS"
);

// Get items from cache
Map<String, Customer> itemsFetched = cache.getBulk(keys, Customer.class);

//Create a dictionary to store updated items
Map<String, CacheItem> itemsUpdated = new HashMap<>();

// Update postal codes of dictionary items
for (Map.Entry<String, Customer> item : itemsFetched.entrySet()) {
    //Update Postal Code
    item.getValue().setPostalCode("05023");

    // Create CacheItem of updated Customer object
    CacheItem updatedCacheItem = new CacheItem(item.getValue());

    // Add uCacheItem to dictionary
    itemsUpdated.put(item.getKey(), updatedCacheItem);
}

if (updateDB(itemsUpdated)) {
    // Insert updated bulk items to Cache
    Map<String, Exception> keysFailedToInsert = cache.insertBulk(itemsUpdated);

    if (keysFailedToInsert.size() > 0) {
        for (Map.Entry<String, Exception> keyFailedToInsert : keysFailedToInsert.entrySet()) {
            System.out.printf("Could not update Item %s in cache due to error : %s", keyFailedToInsert.getKey(), keyFailedToInsert.getValue());
        }
    }
}
# Fetch all products from database
products = fetch_products_from_db()

# Create map of items to be inserted to cache
dictionary = {}

for product in products:
    key = "Product:" + product.get_product_id()
    cache_item = ncache.CacheItem(product)

    # Add items to dictionary
    dictionary[key] = cache_item

keys_failed_to_insert = cache.insert_bulk(dictionary)

if len(keys_failed_to_insert) > 0:
    for entry in keys_failed_to_insert:
        if not keys_failed_to_insert[entry]:
            value = False
else:
    # Any other exception
    value = True
// Fetch all products from database
var products = await this.fetchProductFromDB();

//Create map of items to be added to cache
var dictionary = new Map();

products.forEach(prod => {
    var key = "Product:" + this.product.getProductID();
    var cacheItem = new ncache.CacheItem(this.product);

    //insert dictionary to cache
    this.cache.insert(key,cacheItem);
});

var keysFailedToAdd = this.cache.addBulk(dictionary);

if(keysFailedToAdd.size() > 0)
{
    keysFailedToAdd.forEach(entry => {
        if(entry.getValue() == false)
        {
            var ex = false;
        }
        else
        {
            // Any other exception
        }
    });
}
Product product1 = new Product();
product1.ProductID = 1001;
product1.ProductName = "Chai";
product1.UnitsInStock = 5; //updated units
string key1 = "Product:" + product1.ProductID;

Product product2 = new Product();
product2.ProductID = 1002;
product2.ProductName = "Chang";
product2.UnitsInStock = 6; //updated units

string key2 = "Product:" + product2.ProductID;
string[] keys = { key1, key2 };

CacheItem[] items = new CacheItem[2];
items[0] = new CacheItem(product1);
items[1] = new CacheItem(product2);

IDictionary result = cache.InsertBulk(keys, items, DSWriteOption.None, null);

Update Objects with Asynchronous API

InsertAsync returns the object of the Task class which can further be used according to the business needs of the client application.

  • .NET
  • Java
  • Python
  • Legacy API
string customerKey = $"Customer:ALFKI";

// Get customer from database if not found in cache
if (customer == null)
    customer = FetchCustomerFromDB("ALFKI");

// Update customer's Phone
customer.Phone = "12345-6789";

// Update cutsomer in DB and Cache
if (UpdateDB(customer))
{
    // Adding item asynchronously.
    Task<CacheItemVersion> task = cache.InsertAsync(customerKey, customer);

    // This task object can be used as per your business needs
    if (task.IsCompleted)
    {
        // Get CacheItemVersion object from task result
        CacheItemVersion version = task.Result;
        Console.WriteLine($"Item {customer.CustomerID} has been updated with verion {version.Version}.");
    }
}
String customerKey = "Customer:ALFKI";

// Get customer from database if not found in cache
if (customer == null)
Customer customer = fetchCustomerFromDB("Customer:ALFKI");

// Update customer's Phone
customer.setPhone("12345-6789");

// Update cutsomer in DB and Cache
if (updateDB(customer)) {
    // Adding item asynchronously.
    FutureTask<CacheItemVersion> task = cache.insertAsync(customerKey, customer);

    // Wait for task to complete and get CacheItemVersion object from task result
    CacheItemVersion version = task.get();
    System.out.println("Item " + customer.getCustomerID() + " has been updated with version " + version.getVersion() + ".");
}
# Get product from database
product = fetch_product_from_db()

# Generate a unique cache key for this product string
key = f"Product:{product.get_product_id()}"

# Insert Product object to cache asynchronously
async def insert_async():
    task = cache. insert_async("key", "product")
    value = await task

asyncio.run(insert_async())

# This task object can be used as per your business needs
Product product = new Product();
product.ProductID = 1001;
product.ProductName = "Chai";
product.Category = 5; // updated category

CacheItem cacheItem = new CacheItem(product);
string key = "Product:" + product.ProductID;

cache.InsertAsync(key, cacheItem, DSWriteOption.None, null);

Additional Resources

NCache provides a sample application for Basic Operations on GitHub.

See Also

.NET: Alachisoft.NCache.Client namespace.
Java: com.alachisoft.ncache.client namespace.
Python: ncache.client class.
Node.js: Cache class.

In This Article
  • Prerequisites
  • Update Object in Cache
    • Update Object With Expiration
  • Update Bulk Items in Cache
  • Update Objects with Asynchronous API
  • Additional Resources
  • See Also

Contact Us

PHONE

+1 (214) 764-6933   (US)

+44 20 7993 8327   (UK)

 
EMAIL

sales@alachisoft.com

support@alachisoft.com

NCache
  • NCache Enterprise
  • NCache Professional
  • Edition Comparison
  • NCache Architecture
  • Benchmarks
Download
Pricing
Try Playground

Deployments
  • Cloud (SaaS & Software)
  • On-Premises
  • Kubernetes
  • Docker
Technical Use Cases
  • ASP.NET Sessions
  • ASP.NET Core Sessions
  • Pub/Sub Messaging
  • Real-Time ASP.NET SignalR
  • Internet of Things (IoT)
  • NoSQL Database
  • Stream Processing
  • Microservices
Resources
  • Magazine Articles
  • Third-Party Articles
  • Articles
  • Videos
  • Whitepapers
  • Shows
  • Talks
  • Blogs
  • Docs
Customer Case Studies
  • Testimonials
  • Customers
Support
  • Schedule a Demo
  • Forum (Google Groups)
  • Tips
Company
  • Leadership
  • Partners
  • News
  • Events
  • Careers
Contact Us

  • EnglishChinese (Simplified)FrenchGermanItalianJapaneseKoreanPortugueseSpanish

  • Contact Us
  •  
  • Sitemap
  •  
  • Terms of Use
  •  
  • Privacy Policy
© Copyright Alachisoft 2002 - 2025. All rights reserved. NCache is a registered trademark of Diyatech Corp.
Back to top