I want to add property to existing document (using clues form http://ravendb.net/docs/client-api/partial-document-updates). But before adding want to check if that property already exists in my database.
Is any "special,proper ravendB way" to achieve that?
Or just load document and check if this property is null or not?
You can do this using a set based database update. You carry it out using JavaScript, which fortunately is similar enough to C# to make it a pretty painless process for anybody. Here's an example of an update I just ran.
Note: You have to be very careful doing this because errors in your script may have undesired results. For example, in my code CustomId contains something like '1234-1'. In my first iteration of writing the script, I had:
product.Order = parseInt(product.CustomId.split('-'));
Notice I forgot the indexer after split. The result? An error, right? Nope. Order had the value of 12341! It is supposed to be 1. So be careful and be sure to test it thoroughly.
Example:
Job has a Products property (a collection) and I'm adding the new Order property to existing Products.
ravenSession.Advanced.DocumentStore.DatabaseCommands.UpdateByIndex(
"Raven/DocumentsByEntityName",
new IndexQuery { Query = "Tag:Jobs" },
new ScriptedPatchRequest { Script =
#"
this.Products.Map(function(product) {
if(product.Order == undefined)
{
product.Order = parseInt(product.CustomId.split('-')[1]);
}
return product;
});"
}
);
I referenced these pages to build it:
set based ops
partial document updates (in particular the Map section)
Related
I'm trying to gracefully handle extra many to many relationship data in an ATK4 CRUD object. I can manually add the current entry's linked tables as sub CRUD objects while isEditing(), but in doing so i break the 'Add New' button. Code as follows:
function page_projects($p) {
$crud = $this->add('CRUD');
$crud->setModel('Project', null, array('Title', 'School'));
if($crud->grid){
$crud->grid->addPaginator(10);
$crud->grid->addQuicksearch(array('Title','School'));
}
if($crud->isEditing()){
$vForm = $crud->form;
$keywords = $vForm->add('CRUD');
$keywords->entity_name = 'Keyword';
$keywords->setModel(
$crud->model->load($crud->id)->
ref("mProjectKeywords"));
//Other snipped m:m rels
}
}
The issue is simply that $crud->id is not populated (and shouldn't be) when generating a new entry, which means i can't spawn new sub cruds. A workaround is to use:
if($crud->isEditing() && !is_null($crud->id)) {
when checking isEditing(), but this simply stops the sub CRUDS from being instantiated to avoid having load() throw an exception. I've tried looking at loadAny() and tryLoad() and neither do what i want in a many to many context: load a record if one exists, generate a new one otherwise.
Does anyone know a better way of handling this, and if there's not already one in the framework then what's the best angle for attacking this problem?
In this case that's normal behavior because you simply can't create mProjectKeywords record in database table before you INSERT referenced records in parent tables (Project and Keywords).
I do something like if($crud->isEditing() && !is_null($crud->id)) in my projects too.
That means you first have to save (insert) new record in Project and only then sub-CRUD shows up and you can add referenced records in Project edit form (which reloads automatically after you save new project).
I have a object Ob with several fields f1,..,fn (of different types).
Now a list of object is shown in a GridView and I need to implement the sorting method.
The real problem is:
how can I run
(from ob in Ob_list orderby ob.f1 ascending)
when the sorting field is represented by a string (i.e. "f1")?
Unfortunately I am not able to get it with the reflection (I am not able to do something like ob.GetType().GetField("f1"), this is not mapped into sql code).
I have several fields to possibly sort the rows, which is the best&fastest approach to this?
Thank you very much!
LINQ execution is deferred until you actually enumerate over the results or access the "count", etc. Because of this, you can build up your LINQ statement in stages.
The below code is done in C#, but I'm sure the equivalent is possible in VB.NET.
First setup your basic query:
var query = (from ob in Ob_list);
At this point, nothing has actually gone to the database due to deferred execution.
Next, conditionally add your order by components:
if (sortField == "f1")
{
query = query.OrderBy(o => o.f1);
}
else if (sortField == "f2")
{
query = query.OrderBy(o => o.f2);
}
else
{
//...
}
And finally, collect your results
foreach (var item in query)
{
// Process the item
}
I've found this question: How do I specify the Linq OrderBy argument dynamically?
I'm using Entity Framework, so the first answer did not solved my problem. The second one however, worked great!
Hope it helps!
I have saved certain MDX query and I run them using ADOMD.NET. I get CellSet back which I convert into dataset. All this is working fine. Now the DB team has changed the cube structure. They have updated the DimesnionName, Attribute Name etc. Some dimensions got renamed and some got deleted. Becuase of this I am unable to run my saved queries. I want to create a console application, which will take list of keys ([DimensionName].[AttributeName] or [DimensionName].[AttributeName].[MemeberName] format) and it will tell me following keys does not exists.
Please let me know if this is possible programatically. I dont want to check it manually.
Kindly share a link or code which will help me acheive this.
Thank you.
If you're using ADOMD already this should be no problem, just use the metadata queries:
http://msdn.microsoft.com/en-us/library/ms123485.aspx
Alternatively, AMO is nice http://msdn.microsoft.com/en-us/library/microsoft.analysisservices.aspx
I use it in SSIS for processing, you could easily use it in .Net to test existence of elements:
using Microsoft.AnalysisServices;
...
Server server = new Server();
server.Connect(cubeConnectionString);
Database database = server.Databases.FindByName(databaseName);
Cube cube = database.Cubes.FindByName(cubeName);
foreach (MeasureGroup measureGroup in cube.MeasureGroups)
{
foreach (Partition partition in measureGroup.Partitions)
{
...
}
}
foreach (CubeDimension cubeDimension in cube.Dimensions)
{
Dimension dimension = cubeDimension.Dimension;
var dimName = dimension.Name;
...
}
Finding the names in advance for all the elements you need is probably the hard part (And keeping it all up-to-date).
Would it not be easier to fire all the queries at the cube and try to trap the "no such thing" response?
I have a document in RavenDB that looks looks like:
{
"ItemId": 1,
"Title": "Villa
}
With the following metadata:
Raven-Clr-Type: MyNamespace.Item, MyNamespace
Raven-Entity-Name: Doelkaarten
So I serialized with a type MyNamespace.Item, but gave it my own Raven-Entity-Name, so it get its own collection.
In my code I define an index:
public class DoelkaartenIndex : AbstractIndexCreationTask<Item>
{
public DoelkaartenIndex()
{
// MetadataFor(doc)["Raven-Entity-Name"].ToString() == "Doelkaarten"
Map = items => from item in items
where MetadataFor(item)["Raven-Entity-Name"].ToString() == "Doelkaarten"
select new {Id = item.ItemId, Name = item.Title};
}
}
In the Index it is translated in the "Maps" field to:
docs.Items
.Where(item => item["#metadata"]["Raven-Entity-Name"].ToString() == "Doelkaarten")
.Select(item => new {Id = item.ItemId, Name = item.Title})
A query on the index never gives results.
If the Maps field is manually changed to the code below it works...
from doc in docs
where doc["#metadata"]["Raven-Entity-Name"] == "Doelkaarten"
select new { Id = doc.ItemId, Name=doc.Title };
How is it possible to define in code the index that gives the required result?
RavenDB used: RavenHQ, Build #961
UPDATE:
What I'm doing is the following: I want to use SharePoint as a CMS, and use RavenDB as a ready-only replication of the SharePoint list data. I created a tool to sync from SharePoint lists to RavenDB. I have a generic type Item that I create from a SharePoint list item and that I serialize into RavenDB. So all my docs are of type Item. But they come from different lists with different properties, so I want to be able to differentiate. You propose to differentiate on an additional property, this would perfectly work. But then I will see all list items from all lists in one big Items collection... What would you think to be the best approach to this problem? Or just live with it? I want to use the indexes to create projections from all data in an Item to the actual data that I need.
You can't easily change the name of a collection this way. The server-side will use the Raven-Entity-Name metadata, but the client side will determine the collection name via the conventions registered with the document store. The default convention being to use the type name of the entity.
You can provide your own custom convention by assigning a new function to DocumentStore.Conventions.FindTypeTagName - but it would probably be cumbersome to do that for every entity. You could create a custom attribute to apply to your entities and then write the function to look for and understand that attribute.
Really the simplest way is just to call your entity Doelkaarten instead of Item.
Regarding why the change in indexing works - it's not because of the switch in linq syntax. It's because you said from doc in docs instead of from doc in docs.Items. You probably could have done from doc in docs.Doelkaartens instead of using the where clause. They are equivalent. See this page in the docs for further examples.
I'm developing a WCF Data Service with self tracking entities and I want to prevent clients from inserting duplicated content. Whenever they POST data without providing a value for the data key, I have to execute some logic to determine whether that data is already present inside my database or not. I've written a Change interceptor like this:
[ChangeInterceptor("MyEntity")]
public void OnChangeEntity(MyEntity item, UpdateOperations operations){
if (operations == UpdateOperations.Add)
{
// Here I search the database to see if a matching record exists.
// If a record is found, I'd like to use its ID and basically change an insertion
// into an update.
item.EntityID = existingEntityID;
item.MarkAsModified();
}
}
However, this is not working. The existingEntityID is ignored and, as a result, the record is always inserted, never updated. Is it even possible to do? Thanks in advance.
Hooray! I managed to do it.
item.EntityID = existingEntityID;
this.CurrentDataSource.ObjectStateManager.ChangeObjectState(item, EntityState.Modified);
I had to change the object state elsewhere, ie. by calling .ChangeObjectState of the ObjectStateManager, which is a property of the underlying EntityContext. I was mislead by the .MarkAsModified() method which, at this point, I'm not sure what it does.