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How to add distinct value in database using Entity Framework

IEnumerable<WebsiteWebPage> data = GetWebPages();
foreach (var value in data)
{
if (value.WebPage.Contains(".htm"))
{
WebsiteWebPage pagesinfo = new WebsiteWebPage();
pagesinfo.WebPage = value.WebPage;
pagesinfo.WebsiteId = websiteid;
db.WebsiteWebPages.Add(pagesinfo);
}
}
db.SaveChanges();
I want to add only distinct values to database in above code. Kindly help me how to do it as I am not able to find any solution.

IEnumerable<WebsiteWebPage> data = GetWebPages();
foreach (var value in data)
{
if (value.WebPage.Contains(".htm"))
{
var a = db.WebsiteWebPages.Where(i => i.WebPage == value.WebPage.ToString()).ToList();
if (a.Count == 0)
{
WebsiteWebPage pagesinfo = new WebsiteWebPage();
pagesinfo.WebPage = value.WebPage;
pagesinfo.WebsiteId = websiteid;
db.WebsiteWebPages.Add(pagesinfo);
db.SaveChanges();
}
}
}
This is the code that I used to add distinct data.I hope it helps

In addition to the code sample Furkan Öztürk supplied, Make sure your DB has a constraint so that you cannot enter duplicate values in the column. Belt and braces approach.

I assume that by "distinct values" you mean "distinct value.WebPage values":
// get existing values (if you ever need this)
var existingWebPages = db.WebsiteWebPages.Select(v => v.WebPage);
// get your pages
var webPages = GetWebPages().Where(v => v.WebPage.Contains(".htm"));
// get distinct WebPage values except existing ones
var distinctWebPages = webPages.Select(v => v.WebPage).Distinct().Except(existingWebPages);
// create WebsiteWebPage objects
var websiteWebPages = distinctWebPages.Select(v =>
new WebsiteWebPage { WebPage = v, WebsiteId = websiteid});
// save all at once
db.WebsiteWebPages.AddRange(websiteWebPages);
db.SaveChanges();

Assuming that you need them to be unique by WebPage and WebSiteId
IEnumerable<WebsiteWebPage> data = GetWebPages();
foreach (var value in data)
{
if (value.WebPage.Contains(".htm"))
{
WebsiteWebPage pagesinfo = new WebsiteWebPage();
if (db.WebsiteWebPages.All(c=>c.WebPage != value.WebPage|| c.WebsiteId != websiteid))
{
pagesinfo.WebPage = value.WebPage;
pagesinfo.WebsiteId = websiteid;
db.WebsiteWebPages.Add(pagesinfo);
}
}
}
db.SaveChanges();
UPDATE
To optimize this (given that your table contains much more data than your current list), override your equals in WebsiteWebPage class to define your uniqueness criteria then:
var myWebsiteWebPages = data.select(x=> new WebsiteWebPage { WebPage = x.WebPage, WebsiteId = websiteid}).Distinct();
var duplicates = db.WebsiteWebPages.Where(x=> myWebsiteWebPage.Contains(x));
db.WebsiteWebPages.AddRange(myWebsiteWebPages.Where(x=> !duplicates.Contains(x)));
this is a one database query to retrieve ONLY duplicates and then removing them from the list

You can use the following code,
IEnumerable<WebsiteWebPage> data = GetWebPages();
var templist = new List<WebsiteWebPage>();
foreach (var value in data)
{
if (value.WebPage.Contains(".htm"))
{
WebsiteWebPage pagesinfo = new WebsiteWebPage();
pagesinfo.WebPage = value.WebPage;
pagesinfo.WebsiteId = websiteid;
templist.Add(pagesinfo);
}
}
var distinctList = templist.GroupBy(x => x.WebsiteId).Select(group => group.First()).ToList();
db.WebsiteWebPages.AddRange(distinctList);
db.SaveChanges();
Or you can use MoreLINQ here to filter distinct the list by parameter like,
var res = tempList.Distinct(x=>x.WebsiteId).ToList();
db.WebsiteWebPages.AddRange(res);
db.SaveChanges();

How can I edit the Keywords field in SharePoint using c#?

I can edit other fields like Title and even my own created fields, but I cant figure out how to add in Keywords to a document I upload. This is what I have so far. The error I get says that the Keywords column does not exist. The Keywords fields type is Managed Metadata. Here is a image of where I want to add keywords into Here is a image of where I want to add keywords into
Update: Here is the updated code of what worked
static void AddMetaData(ClientContext ctx, string fName, string kWords )
{
List list = ctx.Web.Lists.GetByTitle("Documents");
ListItemCollection items = list.GetItems(CamlQuery.CreateAllItemsQuery());
ctx.Load(items); // loading all the fields
ctx.ExecuteQuery();
TaxonomySession session = TaxonomySession.GetTaxonomySession(ctx);
var store = session.GetDefaultKeywordsTermStore();
var terms = store.KeywordsTermSet.GetAllTerms();
ctx.Load(store, i => i.DefaultLanguage);
ctx.ExecuteQuery();
var collection = new System.Collections.ObjectModel.Collection<Term>();
var keywords = kWords.Split(';');
foreach (var key in keywords)
{
var filtered = ctx.LoadQuery(terms.Where(t => t.Name == key));
ctx.ExecuteQuery();
var term = filtered.SingleOrDefault();
if (term != null)
collection.Add(term);
}
foreach (var item in items)
{
var taxonomyField = ctx.CastTo<TaxonomyField>(list.Fields.GetByInternalNameOrTitle("Keywords"));
ctx.Load(taxonomyField);
ctx.ExecuteQuery();
taxonomyField.SetFieldValueByCollection(item, collection, store.DefaultLanguage);
item.Update();
ctx.ExecuteQuery();
}
}

It's a taxonomy field so first you have to get your keywords from the managed metadata store:
TaxonomySession session = TaxonomySession.GetTaxonomySession(context);
var store = session.GetDefaultKeywordsTermStore();
var terms = store.KeywordsTermSet.GetAllTerms();
context.Load(store, i => i.DefaultLanguage);
context.ExecuteQuery();
var collection = new System.Collections.ObjectModel.Collection<Term>();
var keywords = new string[] { "Key1", "Key2" };
foreach (var key in keywords)
{
var filtered = context.LoadQuery(terms.Where(t => t.Name == key));
context.ExecuteQuery();
var term = filtered.SingleOrDefault();
if (term != null)
collection.Add(term);
}
Then set field using method contained in TaxonomyField class:
var taxonomyField = context.CastTo<TaxonomyField>(list.Fields.GetByInternalNameOrTitle("Keywords"));
context.Load(taxonomyField);
context.ExecuteQuery();
taxonomyField.SetFieldValueByCollection(item, collection, store.DefaultLanguage);
item.Update();
context.ExecuteQuery();

Lucene query in C# not finding results with punctuation

I have a search bar that executes a lucene query on the "description" field, but it doesn't return results when with apostrophes. For example, I have a product where the description is Herter's® EZ-Load 200lb Feeder - 99018. When I search for "Herter", I get results, but I get no results if I search for "Herter's" or "Herters". This is my search code:
var query = Request.QueryString["q"];
var search = HttpContext.Current.Server.UrlDecode(query);
var rewardProductLookup = new RewardCatalogDataHelper();
RewardProductSearchCriteria criteria = new RewardProductSearchCriteria()
{
keywords = search,
pageSize = 1000,
sortDirection = "desc"
};
IEnumerable<SkinnyItem> foundProducts = rewardProductLookup.FindByKeywordQuery(criteria);
public IEnumerable<SkinnyItem> FindByKeywordQuery(RewardProductSearchCriteria query)
{
var luceneIndexDataContext = new LuceneDataContext("rewardproducts", _dbName);
string fieldToQuery = "rpdescription";
bool sortDirection = query.sortDirection.ToLower().Equals("desc");
MultiPhraseQuery multiPhraseQuery = new MultiPhraseQuery();
var keywords = query.keywords.ToLower().Split(',');
foreach (var keyword in keywords)
{
if (!String.IsNullOrEmpty(keyword))
{
var term = new Term(fieldToQuery, keyword);
multiPhraseQuery.Add(term);
}
}
var booleanQuery = new BooleanQuery();
booleanQuery.Add(multiPhraseQuery, BooleanClause.Occur.MUST);
return
luceneIndexDataContext.BooleanQuerySearch(booleanQuery, fieldToQuery, sortDirection)
.Where(i => i.Fields["eligibleforpurchase"] == "1");
}

The problem here is analysis. You haven't specified the analyzer being used in this case, so I'll assume it's StandardAnalyzer.
When analyzed, the term "Herter's" will be translated to "herter". However, no analyzer is being applied in your FindByKeywordQuery method, so looking for "herter" works, but "herter's" doesn't.
One solution would be to use the QueryParser, in stead of manually constructing a MultiPhraseQuery. The QueryParser will handle tokenizing, lowercasing, and such. Something like:
QueryParser parser = new QueryParser(VERSION, "text", new StandardAnalyzer(VERSION));
Query query = parser.Parse("\"" + query.keywords + "\"");

The single quote is the delimiter for text fields in a query.
Select * FROM Product where Description = 'foo'
You will need to escape or double any single quote your query. try this in the loop.
foreach (var keyword in keywords)
{
if (!String.IsNullOrEmpty(keyword))
{
var term = new Term(fieldToQuery, keyword);
term = term.Replace("'", "''");
multiPhraseQuery.Add(term);
}
}
You could also create an extension method
[DebuggerStepThrough]
public static string SanitizeSQL(this string value)
{
return value.Replace("'", "''").Replace("\\", "\\\\");
}
in which case you could then you could do this in the loop
foreach (var keyword in keywords)
{
if (!String.IsNullOrEmpty(keyword))
{
var term = new Term(fieldToQuery, keyword.SanitizeSQL());
multiPhraseQuery.Add(term);
}
}
Hope this helps.

Elastic search with Nest

I am working on below code, and what I want to do is query by object itself.
For example: I have a search form, that populates objects fields such as below. Then what I want to do is to search Elastic search based on whatever user filled the form with.
ie: below, I want to query the index by searchItem object. How can I do it easily?
class Program
{
static void Main(string[] args)
{
var p = new Program();
var item1 = new Announcement() {Id=1, Title = "john", ContentText = "lorem", Bar = false, Num = 99, Foo = "hellow"};
//p.Index(item1, "add");
var searchItem = new Announcement() {Title="john",Num=99};
ElasticClient.Search<Announcement>();
Console.Read();
}
public void Index(Announcement announcement, String operation)
{
var uriString = "http://localhost:9200";
var searchBoxUri = new Uri(uriString);
var settings = new ConnectionSettings(searchBoxUri);
settings.SetDefaultIndex("test");
var client = new ElasticClient(settings);
if (operation.Equals("delete"))
{
client.DeleteById("test", "announcement", announcement.Id);
}
else
{
client.Index(announcement, "test", "announcement", announcement.Id);
}
}
private static ElasticClient ElasticClient
{
get
{
try
{
var uriString = "http://localhost:9200";
var searchBoxUri = new Uri(uriString);
var settings = new ConnectionSettings(searchBoxUri);
settings.SetDefaultIndex("test");
return new ElasticClient(settings);
}
catch (Exception)
{
throw;
}
}
}
}

You can't :)
NEST cannot infer how to best query only based on a partially filled POCO. Should it OR or AND should it do a nested term query or a term query wrapped in a has_child? You catch my drift.
Nest does have a slick feature called conditionless queries that allow you the write out to entire query like so:
ElasticClient.Search<Announcement>(s=>s
.Query(q=>
q.Term(p=>p.Title, searchItem.Title)
&& q.Term(p=>p.Num, searchItem.Num)
//Many more queries use () to group all you want
)
)
When NEST sees that the argument passed to Term is null or empty it simply wont render that part of the query.
Read more here on how this feature works http://nest.azurewebsites.net/concepts/writing-queries.html

How can I write a LINQ to SQL query to update tags?

I have an image site where users can tag photos much like you can tag a question on Stackoverflow.
I have the following tables:
Images [ID, URL, etc]
Tags [ID, TagName]
ImageTag [TagID, ImageID]
I want to write a method with the signature:
public void UpdateImageTags(int imageId, IEnumerable<string> currentTags)
This method will do the following:
Create any new Tags in currentTags that don't already exist in the Tags table.
Get the old ImageTag's for an image.
Delete any ImageTag's that no longer exist in the currentTags
Add any ImageTag's that are new between the currentTags and oldTags.
Here is my attempt at that method:
public void UpdateImageTags(int imageId, IEnumerable<string> currentTags)
{
using (var db = new ImagesDataContext())
{
var oldTags = db.ImageTags.Where(it => it.ImageId == imageId).Select(it => it.Tag.TagName);
var added = currentTags.Except(oldTags);
var removed = oldTags.Except(currentTags);
// Add any new tags that need created
foreach (var tag in added)
{
if (!db.Tags.Any(t => t.TagName == tag))
{
db.Tags.InsertOnSubmit(new Tag { TagName = tag });
}
}
db.SubmitChanges();
// Delete any ImageTags that need deleted.
var deletedImageTags = db.ImageTags.Where(it => removed.Contains(it.Tag.TagName));
db.ImageTags.DeleteAllOnSubmit(deletedImageTags);
// Add any ImageTags that need added.
var addedImageTags = db.Tags.Where(t => added.Contains(t.TagName)).Select(t => new ImageTag { ImageId = imageId, TagId = t.TagId });
db.ImageTags.InsertAllOnSubmit(addedImageTags);
db.SubmitChanges();
}
}
However, this fails on the line:
db.ImageTags.DeleteAllOnSubmit(deletedImageTags);
With the error:
Local sequence cannot be used in LINQ to SQL implementations of query
operators except the Contains operator.
Is there an easier way I can handle the operation of adding new tags, deleting old ImageTags, adding new ImageTags in LINQ to SQL?

Seems like this would be easiest
public void UpdateImageTags(int imageId, IEnumerable<string> currentTags)
{
using (var db = new ImagesDataContext())
{
var image = db.Images.Where(it => it.ImageId == imageId).First()
image.Tags.Clear();
foreach(string s in currentTags)
{
image.Tags.Add(new Tag() { TagName = s});
}
db.SubmitChanges();
}
}
This might have to be modified slightly for LinqtoSQL. EF is what i have been using most recently. Also this is dependent on Lazy loading being enabled. If it is not, you will have to force the include of the image tags.

Here is a helper method to deal with many-to-many relationships:
public static void UpdateReferences<FK, FKV>(
this EntitySet<FK> refs,
Expression<Func<FK, FKV>> fkexpr,
IEnumerable<FKV> values)
where FK : class
where FKV : class
{
Func<FK, FKV> fkvalue = fkexpr.Compile();
var fkmaker = MakeMaker(fkexpr);
var fkdelete = MakeDeleter(fkexpr);
var fks = refs.Select(fkvalue).ToList();
var added = values.Except(fks);
var removed = fks.Except(values);
foreach (var add in added)
{
refs.Add(fkmaker(add));
}
foreach (var r in removed)
{
var res = refs.Single(x => fkvalue(x) == r);
refs.Remove(res);
fkdelete(res);
}
}
static Func<FKV, FK> MakeMaker<FKV, FK>(Expression<Func<FK, FKV>> fkexpr)
{
var me = fkexpr.Body as MemberExpression;
var par = Expression.Parameter(typeof(FKV), "fkv");
var maker = Expression.Lambda(
Expression.MemberInit(Expression.New(typeof(FK)),
Expression.Bind(me.Member, par)), par);
var cmaker = maker.Compile() as Func<FKV, FK>;
return cmaker;
}
static Action<FK> MakeDeleter<FK, FKV>(Expression<Func<FK, FKV>> fkexpr)
{
var me = fkexpr.Body as MemberExpression;
var pi = me.Member as PropertyInfo;
var assoc = Attribute.GetCustomAttribute(pi, typeof(AssociationAttribute))
as AssociationAttribute;
if (assoc == null || !assoc.DeleteOnNull)
{
throw new ArgumentException("DeleteOnNull must be set to true");
}
var par = Expression.Parameter(typeof(FK), "fk");
var maker = Expression.Lambda(
Expression.Call(par, pi.GetSetMethod(),
Expression.Convert(Expression.Constant(null), typeof(FKV))), par);
var cmaker = maker.Compile() as Action<FK>;
return cmaker;
}
Usage:
IEnumerable<Tag> values = ...;
Image e = ...;
e.ImageTags.UpdateReferences(x => x.Tag, tags);