The do nothing SearchProvider

With Find-backed IEntrySearchService in the previous post , we can now put SearchProvider to rest. There are, however, parts of the framework that still rely on SearchManager, and it expects a configured, working SearchProvider. The Full search index job, and the Incremental search index job are two examples. To make sure we don’t break the system, we might want to give SearchManager something to chew on. A do nothing SearchProvider that is!

And we need a DoNothingSearchProvider

    public class DoNothingSearchProvider : SearchProvider
        public override string QueryBuilderType => GetType().ToString();

        public override void Close(string applicationName, string scope) { }
        public override void Commit(string applicationName) { }
        public override void Index(string applicationName, string scope, ISearchDocument document) { }
        public override int Remove(string applicationName, string scope, string key, string value)
        { return 42; }

        public override void RemoveAll(string applicationName, string scope)
        public override ISearchResults Search(string applicationName, ISearchCriteria criteria)
            return new SearchResults(new SearchDocuments(), new CatalogEntrySearchCriteria());


And a DoNothingIndexBuilder

public class DoNothingIndexBuiler : ISearchIndexBuilder
        public SearchManager Manager { get; set; }
        public IndexBuilder Indexer { get; set; }

        public event SearchIndexHandler SearchIndexMessage;

        public void BuildIndex(bool rebuild) { }
        public bool UpdateIndex(IEnumerable<int> itemIds) { return true; }

What remains is simply register them in your appsettings.json

                                       "SearchOptions":  {
                                                             "DefaultSearchProvider":  "DoNothingSearchProvider",
                                                             "MaxHitsForSearchResults":  1000,
                                                             "IndexerBasePath":  "[appDataPath]/Quicksilver/SearchIndex",
                                                             "IndexerConnectionString":  "",
                                                             "SearchProviders":  [
                                                                "Name": "DoNothingSearchProvider",
                                                                "Type": "EPiServer.Reference.Commerce.Site.Infrastructure.Indexing.DoNothingSearchProvider, EPiServer.Reference.Commerce.Site",
                                                                "Parameters": {
                                                                  "queryBuilderType": "EPiServer.Reference.Commerce.Site.Infrastructure.Indexing.DoNothingSearchProvider, EPiServer.Reference.Commerce.Site",
                                                                  "storage": "[appDataPath]/Quicksilver/SearchIndex",
                                                                  "simulateFaceting": "true"
                                                             "Indexers":  [
                                                                                  "Name":  "catalog",
                                                                                  "Type":  "EPiServer.Reference.Commerce.Site.Infrastructure.Indexing.DoNothingIndexBuilder, EPiServer.Reference.Commerce.Site"

And that’s it.

Use Find for CSR UI

If you have been using Find, you might be surprised to find that CSR UI uses the SearchProvider internally. This is a bit unfortunate because you likely are using Find, and that creates unnecessary complexity. For starter, you need to configure a SearchProvider, then you need to index the entries, separately from the Find index. If you install EPiServer.CloudPlatform.Commerce, it will setup the DXPLucenceSearchProvider for you, which is basically a wrapper of LuceneSearchProvider to let it work on DXP (i.e. Azure storage). But even with that, you have to index your entries anyway. You can use FindSearchProvider, but that actually just creates another problem – it uses a different index compared to Find, so you double your index count, yet you have still make sure to index your content. Is there a better way – to use the existing Find indexed content?

Yes, there is

Searches for entries in CSR is done by IEntrySearchService which the default implementation uses the configured SearchProvider internally . Fortunately for us, as with most thing in Commerce, we can create our own implementation and inject it. Now that’s with a caveat – IEntrySearchService is marked as BETA remark, so prepare for some breaking changes without prior notice. However it has not changed much since its inception (funny thing, when I checked for its history, I was the one who created it 6 years ago, in 2017. Feeling old now), and if it is changed, it would be quite easy to adapt for such changes.

IEntrySearchService is a simple with just one method:

IEnumerable<int> Search(string keyword, MarketId marketId, Currency currency, string siteId);

It is a bit weird to return an IEnumerable<int> (what was I thinking ? ), but it was likely created as a scaffolding of SearchManager.Search which returns an IEnumerable<int>, and was not updated later. Anyway, an implementation using Find should look like this:

    public class FindEntrySearchService : IEntrySearchService
        private EPiServer.Find.IClient _searchClient;

        public FindEntrySearchService(EPiServer.Find.IClient searchClient) => _searchClient = searchClient;

        public IEnumerable<int> Search(string keyword, MarketId marketId, Currency currency, string siteId)
            return _searchClient.Search<EntryContentBase>()
                 .Filter(x => x.MatchMarketId(marketId))
                 .Filter(x => x.SiteId().Match(siteId))
                 .Filter(x => FilterPriceAvailableForCurrency<IPricing>(y => y.Prices(), currency))
                 .Select(x => x.ContentLink.ID);

        public FilterExpression<Price> FilterPriceAvailableForCurrency<T>(Expression<Func<T, IEnumerable<Price>>> prices, Currency currency)
            var currencyCode = currency != null ? currency.CurrencyCode : string.Empty;

            return new NestedFilterExpression<T, Price>(prices, price => price.UnitPrice.Currency.CurrencyCode.Match(currencyCode), _searchClient.Conventions);

Note that I am not an expert on Find, especially on NestedFilterExpression, so my FilterPriceAvailableForCurrency might be wrong. Feel free to correct it, the code is not copyrighted and is provided as-is.

As always, you need to register this implementation for IEntrySearchService. You can add it anywhere you like as long as it’s after .AddCommerce.

_services.AddSingleton<IEntrySearchService, FindEntrySearchService>();

Optimizing an interesting query

It’s not a secret, I love optimizing things. In a sense, I am both an Optimizer (literally) and an optimizer. And today we will be back to basic – optimizing a tricky SQL query.

The query in question is this particular stored procedure ecf_CatalogNode_GetAllChildNodes, this is used to get all children nodes of specific nodes. It is used in between to find all entries that are direct, or indirect children of specific nodes. Why, you might ask, because when you change the url segment of the node, you want to make sure that all entries that are under that node, will have their indexed object refreshed.

Let’s take a look at this stored procedure, this is how it looks like

CREATE PROCEDURE [dbo].[ecf_CatalogNode_GetAllChildNodes]
    @catalogNodeIds udttCatalogNodeList readonly
    WITH all_node_relations AS 
        SELECT ParentNodeId, CatalogNodeId AS ChildNodeId FROM CatalogNode
        WHERE ParentNodeId > 0
        SELECT ParentNodeId, ChildNodeId FROM CatalogNodeRelation
    hierarchy AS
            '|' + CAST(n.CatalogNodeId AS nvarchar(4000)) + '|' AS CyclePrevention
        FROM @catalogNodeIds n
        UNION ALL
            children.ChildNodeId AS CatalogNodeId,
            parent.CyclePrevention + CAST(children.ChildNodeId AS nvarchar(4000)) + '|' AS CyclePrevention
        FROM hierarchy parent
        JOIN all_node_relations children ON parent.CatalogNodeId = children.ParentNodeId
        WHERE CHARINDEX('|' + CAST(children.ChildNodeId AS nvarchar(4000)) + '|', parent.CyclePrevention) = 0
    SELECT CatalogNodeId FROM hierarchy

I previously wrote about the relations between entities in Commerce catalog, here Commerce relation(ship), a story – Quan Mai’s blog ( , so relations between nodes can be a bit complicated – a node can have one true parent defined in CatalogNode table, and then other “linked” nodes in CatalogNodeRelation . So to find all children – and grand children of a node, you need to get from both.

Getting children of a node from CatalogNode or CatalogNodeRelation is simple, but things become more complicated when you have to get grandchildren, then great-grandchildren, and so on, and so forth. with that, CTE needs to be used in a recursive way. But then there is a problem arises – there is a chance, small, but still, that the data was added in a correct way, so circular reference is possible. i.e. A is a parent of B, which is a parent of C, and itself is a parent of A. To stop the SP from running forever, a check needs to be added to make sure any circular reference is cut short.

This brings back memory as the first ever support case I worked on at Optimizely (then Episerver) was with a circular reference. The site would crash whenever someone visited the catalog management in Commerce Manager. That was around June, 2012 (feeling old now?). My “boss” at that time involuntarily volunteered me for the case. See what you made me do, boss.

Now you can grasp the basic of what the SP does – let’s get back to the original problem. it’s slow to run especially with big catalog and complex node structure. As always, to optimize everything you need to find the bottleneck – time to fire up SQL Server Management Studio and turn on the Actual Execution Plan

I decided to go with 66, the “root” catalog node. this query yield around 18k rows

declare @Nodes udttCatalogNodeList 

insert into @Nodes (CatalogNodeId) select 66

exec ecf_CatalogNode_GetAllChildNodes @Nodes

and also 18s of execution.

Mind you, this is on my machine with pretty powerful CPU (AMD Ryzen 7 5800x, 8 cores 16 threads), and a very fast nvme PCIe SSD (Western Digital Black SN850 2TB). If this was executed on Azure Sql database for example, a timeout is almost certainly guaranteed. So time of execution should only be compared relatively with each other.

If we look at the execution plan, it is quite obvious where the bottleneck is. A scan on CatalogNode table is heavy (it read 79M rows on that operation). As suggest by Anders from Timeout when deleting CatalogNodes from a large catalog (, adding a non clustered index on ParentNodeId column would improve it quite a lot. And indeed it does. The execution time is reduced to 5 second.

And the number of rows read on CatalogNode reduced to just 17k

This is of course a very nice improvement. But the customer reported that it is not enough and the SP is still giving timeout, i.e. further optimization is needed.

Naturally, the next step would be to see if we can skip the circular check. It was added as a safe measure to avoid bad data. It should not be there, as the check should be performed at data modification. But it is there for historical reasons and we can’t just change it, not trivially. So let’s try it for our curiousity.

The modified query looks like this (basically just commented out any code related to the CyclePrevention

ALTER PROCEDURE [dbo].[ecf_CatalogNode_GetAllChildNodes]
    @catalogNodeIds udttCatalogNodeList readonly
    WITH all_node_relations AS 
        SELECT ParentNodeId, CatalogNodeId AS ChildNodeId FROM CatalogNode
        WHERE ParentNodeId > 0
        SELECT ParentNodeId, ChildNodeId FROM CatalogNodeRelation
    hierarchy AS
			--, '|' + CAST(n.CatalogNodeId AS nvarchar(4000)) + '|' AS CyclePrevention
        FROM @catalogNodeIds n
        UNION ALL
            children.ChildNodeId AS CatalogNodeId
			--, parent.CyclePrevention + CAST(children.ChildNodeId AS nvarchar(4000)) + '|' AS CyclePrevention
        FROM hierarchy parent
        JOIN all_node_relations children ON parent.CatalogNodeId = children.ParentNodeId
        --WHERE CHARINDEX('|' + CAST(children.ChildNodeId AS nvarchar(4000)) + '|', parent.CyclePrevention) = 0
    SELECT CatalogNodeId FROM hierarchy

And the improvement is quite impressive (more than I expected), the query completes almost instantly (less than 1s). The read on CatalogNodeRelation significantly reduced

A word of warning here, execution plan can’t be simply compared as-is. If I run two versions side by side, it gives quite misleading comparison

Even though the top one (without the circular reference check) is much faster than the original (the bottom one), SQL Server estimates that the first is slower (almost 2x slower than the second). So execution plan should be used to see what has been done and what is likely the bottleneck inside a query, it should not be used as comparison between queries. In most cases, comparing statistics using set statistics io on is the best way to compare.

If not for the fact that we are changing the behavior of the stored procedure, I would be happy with this approach. The chance of running into circular reference is small, but it is not zero. As we said, we can in theory gating the relation during insert/updating, but that would be too big a change to start with. This is one of constraint as we work at framework level – we have to step carefully to not break anything. A breaking change is bad, but a data corruption is simply unacceptable. I spent a few hours (probably more than I should) trying to optimize the circular reference check, but no better solution is found.

The next approach would be – as we can guess, to make sure that we get rid of the Clustered Index Scan happened on the CatalogNodeRelation table. The solution would be quite simple, a non clustered index on the `ParentNodeId should be enough.

Great success. The performance is comparable with the “non circular reference check” approach.

As adding an index is a non breaking change (and albeit in some cases it can cause performance regression, like in A curious case of SQL execution plan – Quan Mai’s blog ( , but it is rare, also, in this case the cardinality of the ParentNodeId is most likely quite well distributed).

That is all for today. Hopefully you learn one thing or two about optimizing queries in your daily works.

Delete orphaned assets

I was asked this question: we have about 3TB of assets, any way to clean it up.

These days, storage is cheap, but still not free. and big storage means you need space for back up. and with that, bandwidth and time.

Is there away to clean up things you no longer need?


Optimizely Content already has a scheduled job named Remove Abandoned BLOBs, but this job only removes the blobs that have no content associated. I.e. the content is deleted by IContentRepository.Delete but the blob was left behind. The job uses the log to find out which content were deleted, then find those blobs.

How’s about the assets that still have contents associated with them, but not used anywhere? Time to get your hands dirty!

Due to the nature of this task, it is best to make it a scheduled job.

All of the assets are children under the global asset root. By iterating over them, we can check if each of them is being used by another content. If not, we will add them to a list for later delete. Before deleting the content, we will find the blob and then delete it as well. Easy, right?

To get the content recursively we use this little piece of code

        public virtual IEnumerable<T> GetAssetRecursive<T>(ContentReference parentLink, CultureInfo defaultCulture) where T : MediaData
            foreach (var folder in LoadChildrenBatched<ContentFolder>(parentLink, defaultCulture))
                foreach (var entry in GetAssetRecursive<T>(folder.ContentLink, defaultCulture))
                    yield return entry;

            foreach (var entry in LoadChildrenBatched<T>(parentLink, defaultCulture))
                yield return entry;

        private IEnumerable<T> LoadChildrenBatched<T>(ContentReference parentLink, CultureInfo defaultCulture) where T : IContent
            var start = 0;

            while (!_isStopped)
                var batch = _contentRepository.GetChildren<T>(parentLink, defaultCulture, start, 50);
                if (!batch.Any())
                    yield break;
                foreach (var content in batch)
                    // Don't include linked products to avoid including them multiple times when traversing the catalog
                    if (!parentLink.CompareToIgnoreWorkID(content.ParentLink))

                    yield return content;
                start += 50;

And we will start from SiteDefinition.Current.GlobalAssetsRoot, and use IContentRepository.GetReferencesToContent to see if it is used in any content (both CMS and Catalog). If not, we add it to a list. Later, we use IPermanentLinkMapper to see if it has any blob associated, and delete that as well

            foreach (var asset in GetAssetRecursive<MediaData>(SiteDefinition.Current.GlobalAssetsRoot, CultureInfo.InvariantCulture))
                if (!_contentRepository.GetReferencesToContent(asset.ContentLink, false).Any())

                if (toDelete.Count % 50 == 0)
                    var maps = _permanentLinkMapper.Find(toDelete);
                    foreach (var map in maps)
                        _contentRepository.Delete(map.ContentReference, true, EPiServer.Security.AccessLevel.NoAccess);
                        var container = Blob.GetContainerIdentifier(map.Guid);
                        //Probably redundency, can just delete directly
                        var blob = _blobFactory.GetBlob(container);
                        if (blob != null)
                        OnStatusChanged($"Deleting asset with id {map.ContentReference}");

We need another round of delete after the while loop to clean up the left over (or if we have less than 50 abandoned assets)

And we’re done!

Testing this job is simple – uploading a few assets to your cms and do not use it anywhere, then run the job. it should delete those assets.

Things to improve: we might want to make sure only assets that created more than a certain number of days ago are deleted. This allows editors to upload assets for later uses without having to use them immediately.

The code has been open sourced at vimvq1987/DeleteUnusedAssets: Delete unused assets from an Optimizely/Episerver site ( , and I have uploaded a nuget package to Packages ( to be reviewed.

Skip validating carts

Carts are meant to be validated. Prices changed, customers add more quantity than allowed, promotions expired, stock ran out, etc.. All kinds of stuffs that make the items in carts need validation to make sure they up to date, and be ready to be converted to an order.

However, there are cases when you don’t want your carts to be validated. The most common case is of course, wish list – a special cart that allows customer to add items to, just to keep track of. You certainly don’t want to touch it. Another example is quote – when you give a specific item at specific price for a customer, and you don’t want it to be automatically changed to the public prices, which is different from that said price.

By default, when it is called to validate a cart, these things will be done:

  • Remove items that no longer available (either deleted or end of line)
  • Update prices of the items to the latest applicable prices, or remove items that have no prices.
  • Update quantity of the items (to comply with the settings or in stock quantity), or remove items that are out of stock
  • Apply promotions
  • Update quantity again (As promotions could do things like adding free items to the cart)

There are two ways you can avoid carts being validated, let’s see what we can do.

The “Wish list names” route

With OrderOptions you can set certain wishlist names to be exempted from the validation, using WishListCartNames. By default, it’s only “Wishlist”, but you can set several using the comma separator, like this

orderOptions.WishListCartNames = "Wishlist,Quote";

However there is a caveat, with this approach, carts in those names will not be shown in the Order Management (If you want, you can change that, however it is not an easy or quick one)

The OrderValidationService route

The validation of carts (or rather, order types in general) is done by OrderValidationService. And that class is meant to be extended if necessary. Here is how you would avoid validation carts with name “Quote”, using OrderValidationService

    public class CustomOrderValidationService : OrderValidationService
        public CustomOrderValidationService(ILineItemValidator lineItemValidator, IPlacedPriceProcessor placedPriceProcessor, IPromotionEngine promotionEngine, IInventoryProcessor inventoryProcessor, OrderOptions orderOptions) : base(lineItemValidator, placedPriceProcessor, promotionEngine, inventoryProcessor, orderOptions)

        public override IDictionary<ILineItem, IList<ValidationIssue>> ValidateOrder(IOrderGroup orderGroup)
            if (orderGroup.Name.Equals("Quote", System.StringComparison.OrdinalIgnoreCase))
                return new Dictionary<ILineItem, IList<ValidationIssue>>();
            return base.ValidateOrder(orderGroup);

And as OrderValidationService is registered by ServiceConfiguration attribute, you can register yours by

services.AddTransient<OrderValidationService, CustomOrderValidationService>();

One caveat though, making changes to OrderValidationService means those changes will apply to the entire website, so make sure the changes are actually the ones you want site-wide, not just in specific places.

Index only Catalog content

If you are using Find to index your content, you likely have used the Find Indexing job – which would index everything in one go. Today I stumped upon this question – A way to run indexing job for Commerce only | Optimizely Develope – and it is a good one – if you have many of content in CMS side, and they don’t change that often, if at all – you certain don’t want to waste time and resource in trying to reindex them again. Is there away to just index catalog content?

Yes, there is. It is a bit hacky solution, but it can certain work. But first, let’s dive in on how Find indexing job does it work. It relies on IIndexingJobService , which itself relies on ContentIndexer to do the job. In its turn, ContentIndexer uses a list of IReindexInformation to know which content to index, and in which languages. Here’s what it looks like

    public interface IReindexInformation
        /// <summary>
        /// Content links to be reindexed.
        /// </summary>
        IEnumerable<ReindexTarget> ReindexTargets { get; }

        /// <summary>
        /// Gets the root to index.
        /// </summary>
        ContentReference Root { get; }

It has one Root, and multiple ReindexTarget, which contains

    public class ReindexTarget
        /// <summary>
        /// The content references.
        /// </summary>
        public IEnumerable<ContentReference> ContentLinks { get; set; }

        /// <summary>
        /// The languages the collection of <see cref="ContentReference"/> are enabled on.
        /// </summary>
        public IEnumerable<CultureInfo> Languages { get; set; }

        /// <summary>
        /// The site that the collection of <see cref="ContentReference"/> appears on
        /// or <c>null</c> if unknown.
        /// </summary>
        public SiteDefinition SiteDefinition { get; set; }

As you might have guessed, Commerce has its own IReindexInformation to index catalog content. If we can only use that to run our job. This is how our “hack” begins

The interface IContentIndexer has no method to control the IReindexInformation`, but the default implementation ContentIndexer does. We set it to the only one we need, so here it is

        List<IReindexInformation> targets;
        var contentIndexer = _contentIndexer as ContentIndexer;
        if (contentIndexer != null)
            targets = contentIndexer.ReindexInformation.ToList();
            var commerceReIndexInformation = targets.FirstOrDefault(x => x.GetType() == typeof(CommerceReIndexInformation));
            contentIndexer.ReindexInformation = new List<IReindexInformation>() { commerceReIndexInformation };

            contentIndexer.ReindexInformation = targets;

A note is that you will still see the “Indexing Global assets and other data” message, because IIndexingJobService implementation will go through all SiteDefinition regardless and show that message, but the internal ContentIndexer will skip if the SiteDefinition passed to it does not match the SiteDefinition in the IReindexInformation (and for CommerceReIndexInformation it’s SiteDefinition.Empty

As I mentioned in the beginning, this is a bit hacky solution, as you have to cast IContentIndexer to its concrete implementation. The proper solution would be implement IContentIndexer yourself. Given that’s not a trivial job, I’ll leave at that.

Loading the contacts/organizations, the right way

If you have been using Business Foundation, you most likely know about a limitation – you can only load the first 1000 objects using the GetXXX methods. For example, by using CustomerContext.Current.GetOrganizations(), you can load the first 1000 organizations. In theory, you can get more objects by changing the value of MaxObjectsList. However, changing that has consequences. Changing that will affect all types of objects, including contacts, organizations, and your custom objects. Also, loading too much in one go is almost never a good idea.

Is there a better way?

Yes, of course – which is why we have this blog post

There is a “hidden” method from base class of Business Foundation – BusinessManager that takes paging parameters

public static EntityObject[] List(string metaClassName, FilterElement[] filters, SortingElement[] sorting, int? start, int? count)

You will need to convert the results to the type you want. Note that all Business Foundation objects are inherited from EntityObject. So if you want to get the contacts by paging, it would look like this:

                var contacts = BusinessManager.List(ContactEntity.ClassName, new FilterElement[0], new SortingElement[] { new SortingElement(sortField, sortType) }, startIndex, recordsToRetrieve)

Let’s go through the parameters one by one.

  • The first you need is the class name of your objects. For contacts, you can use ContactEntity.ClassName as shown above. For organizations, OrganizationEntity.ClassName
  • Next one is the filter. As you are trying to load all objects, you can just pass in an empty (but not null) instance – new FilterElement[0]
  • Third one is how you want to sort it. If you pass an empty array, it will be sort by default. If you want to sort by Name for example, set your sortField to Name and sortType to one of SortingElementType (Asc or Desc)
  • Forth and fifth ones are what we are looking for, they’re simply paging parameters – which position to start getting, and how many objects to get. Combine this with a simple while loop, you can get all of your Business Foundation objects.

And that’s about it, my friends.

What’s about caching?

Caching with list is always tricky – as you have to keep track of each item in the list to make sure you invalidate the list cache if one of the item is changed (updated/removed). For the purpose of just loading all contacts/organizations, it is probably better to just skip caching, for simplicity.

Delete property no longer available in code

Recently I stumped upon this question Removing a property that no longer exists in the code ( . it’s a valid (and even good) question. It is easy to add a new property to your catalog content type – you can simply add a new property to the model, build and start the site. However the opposite is not easy. In Commerce 14 at least.

A property for the strongly typed content type, is actually mapped and backed by a MetaField in MetaDataPlus system (of course unless you specifically tell it not to, by using IgnoreMetaDataPlusSynchronization attribute). When you add a new property to your content type, build and start your site, your content type is scanned and metafields will be created if necessary. However, if you delete a property from your content type, the scanner will just leave the metafield there. There are a few reasons for that. Firstly, it allows loosely typed content type, i.e. content types with none, or only a few property defined. If you have used some kind of external PIM, you’ll understand why it is important. Lastly, because the property can be mapped with a metafield of different name, the scanner might have trouble figuring out which metafield to delete. All in all, keeping the metafields is the sensible (if not the right) choice.

Then what to do if you want to delete the property and also clean up the metafield? With Commerce 13 and earlier, you can detach a MetaField from its MetaClass(s), then delete it using Commerce Manager. With the dead of CM in Commerce 13, what is your option?

By using code, of course. There are a few APIs – namely MetaField and MetaClass that can be used for that purpose. Note that there are two MetaField and MetaClass, and only the ones in Mediachase.MetaDataPlus.Configurator namespace are what we want (the others are for Business Foundation)

Enough for chit chat, this is the code that you would need to run

        private void DeleteMetaField(string metafieldName)
            var metaField = MetaField.Load(CatalogContext.MetaDataContext, metafieldName);
            if (metaField == null)
            foreach (int metaClassId in metaField.OwnerMetaClassIdList)
                var metaClass = MetaClass.Load(CatalogContext.MetaDataContext, metaClassId);
                if (metaClass == null)
            MetaField.Delete(CatalogContext.MetaDataContext, metaField.Id);

It is pretty straightforward. We load the MetaField by its name, if it is not null, then we remove it from all MetaClass that are using it, then eventually delete it.

In beginning of this post we mentioned strongly typed content type, but note that order system also uses the same metaclass/metafield system, so this code can be used for them as well.

This piece of code can be used in an admin-privilege controller to delete metafields on demand. Until Commerce 14 allows you to do it with a proper UI.

Storing 100.000 prices per SKU – part 1

One of the questions I have received, from time to time, is that how to store a lot of prices per SKU in Optimizely (B2C) Commerce Cloud. While this is usually a perfect candidate for Optimizely B2B Commerce, there are many customers invested in B2C and want to make the best out of it. Is it possible?

It’s important to understand the pricing system of Optimizely Commerce (which is, written in detail in my book – shameless plug). But in short:

  • There are two price systems, IPriceService and IPriceDetailService
  • One is handling prices in batch – i.e. prices per SKU (IPriceService), and one is handling prices per individual price (IPriceDetailService)
  • Both are cached in latest version (cache for IPriceDetailService was added in late 13.x version)

With that in mind, it would be very problematic if you use IPriceService for such high number of prices per SKU, because each time you save a price, you save a lot of prices at once (same as loading prices). This is how the default IPriceService implementation saves prices of a SKU

create procedure dbo.ecf_Pricing_SetCatalogEntryPrices
    @CatalogKeys udttCatalogKey readonly,
    @PriceValues udttCatalogEntryPrice readonly
    begin try
        declare @initialTranCount int = @@TRANCOUNT
        if @initialTranCount = 0 begin transaction

        delete pv
        from @CatalogKeys ck
        join dbo.PriceGroup pg on ck.CatalogEntryCode = pg.CatalogEntryCode
        join dbo.PriceValue pv on pg.PriceGroupId = pv.PriceGroupId

        merge into dbo.PriceGroup tgt
        using (select distinct CatalogEntryCode, MarketId, CurrencyCode, PriceTypeId, PriceCode from @PriceValues) src
        on (    tgt.CatalogEntryCode = src.CatalogEntryCode
            and tgt.MarketId = src.MarketId
            and tgt.CurrencyCode = src.CurrencyCode
            and tgt.PriceTypeId = src.PriceTypeId
            and tgt.PriceCode = src.PriceCode)
        when matched then update set Modified = GETUTCDATE()
        when not matched then insert (Created, Modified, CatalogEntryCode, MarketId, CurrencyCode, PriceTypeId, PriceCode)
            values (GETUTCDATE(), GETUTCDATE(), src.CatalogEntryCode, src.MarketId, src.CurrencyCode, src.PriceTypeId, src.PriceCode);

        insert into dbo.PriceValue (PriceGroupId, ValidFrom, ValidUntil, MinQuantity, MaxQuantity, UnitPrice)
        select pg.PriceGroupId, src.ValidFrom, src.ValidUntil, src.MinQuantity, src.MaxQuantity, src.UnitPrice
        from @PriceValues src
        left outer join PriceGroup pg
            on  src.CatalogEntryCode = pg.CatalogEntryCode
            and src.MarketId = pg.MarketId
            and src.CurrencyCode = pg.CurrencyCode
            and src.PriceTypeId = pg.PriceTypeId
            and src.PriceCode = pg.PriceCode

        delete tgt
        from dbo.PriceGroup tgt
        join @CatalogKeys ck on tgt.CatalogEntryCode = ck.CatalogEntryCode
        left join dbo.PriceValue pv on pv.PriceGroupId = tgt.PriceGroupId
        where pv.PriceGroupId is null

        if @initialTranCount = 0 commit transaction
    end try
    begin catch
        declare @msg nvarchar(4000), @severity int, @state int
        select @msg = ERROR_MESSAGE(), @severity = ERROR_SEVERITY(), @state = ERROR_STATE()
        if @initialTranCount = 0 rollback transaction
        raiserror(@msg, @severity, @state)
    end catch

If you have experience with SQL (which you probably should), you will see that it’s a deletion of rows in PriceValue that have CatalogEntryCode same as , then a merge, then a deletion of left over rows. To make matters worse, IPriceService system stores data on 3 tables: PriceValue, PriceGroup and PriceType. Imagine doing that with a few dozen of thousands rows.

Even if you change just one price, all prices of that specific SKU will be touched. It’d be fine if you have like ten prices, but if you have ten thousands prices, it’ll be a huge waste.

Not just that. To save one price, you would still need to load all prices of that specific SKU. That’s two layers of waste: the read operations at database layer, and then on application, a lot of price objects will need to be constructed, and then you need to recreate a datatable to send all the data back to the database to do the expensive operation above.

And wait, because the prices saved to IPriceService needs to be synchronized to IPriceDetailService (however, you can disable this). Prices that were changed (which is, all of them) need to be replicated to another table.

So in short, IPriceService was not designed to handle many prices per SKU. If you have less than a few hundred prices per SKU (on average), it’s fine. But if you have more than 1000 prices per SKU, it’s time to look at other options.

Where to store big collection data

No, I do not mean that big, big data (in size of terabytes or more). It’s big collection, like when you have a List<string> and it has more than a few hundreds of items. Where to store it?

Naturally, you would want to store that data as a property of a content. it’s convenient and it just works, so you definitely can. But the actual question is: should you?

It’s as simple as this

public virtual IList<String> MyBigProperty {get;set;}

But under the hood, it’s more than just … that. Let’s ignore UI for a moment (rendering such long list is a bad UX no matters how you look at it, but you can simply ignore rendering that property by appropriate attributes), and focus on the backend aspects of it.

List<T> properties are serialized as a long strings, and save at once to database. If you have a big property in your content, this will happen every time you load your content:

  • The data must be read from database, then transferred through the network
  • The data must be parsed to create an array (the underlying data structure of List<T>. The original string is tossed away.
  • Now you have a big array that you might not use every time. it’s just there taking your previous LOH (as with the original string)

Same thing happens when you actually save that property

  • The data must be serialized as string, the List<T> is now tossed away
  • The data then must be transferred through the network
  • The data then saved to database. Even though it is a very long string and you changed, maybe 10 characters, it’s completely rewritten. Due to its size, there might be multiple page writes needed.

As you can see, it can create a lot of waste, especially if you rarely use that property. To make the matter worse, due to the size of the property, it means they are taking up space in LOH (large objects heap).

And imagine if you have such properties in each and every of your content. The waste is multiplied, and your site is now at risk of some frequent Gen 2 Garbage collection. Nobody likes visiting a website that freezes (if not crashes) once every 30 minutes.

Then when to store such big collection data?

The obvious answer is … somewhere else. Without other inputs, it’s hard to give you some concrete suggestions, but how’s about a normalized custom table? You have the key as the content reference, and the other column is each value of the list. Just an idea. Then you only load the data when you absolutely need it. More work, yes, but it’s the better way to do it.

Just a reminder that whatever you do, just stay away from DDS – Dynamic Data Store. It’s the worst option of all. Just, don’t 🙂