Entities
We have an entity called Product which is loaded using NHibernate.
Product has a category which NHibernate happily populates for me.
Database
In the database, Product has a foreign key for category.
Scenario
User edits this Product (via a web interface) and chooses a different category (say instead of "Fish" we select "Veg").
This is probably a dropdown list, with each category shown. When they choose a different category we get an int key.
Problem
Obviously we now want to save the changes to Product but in effect the only change is to save a new int (say 2, instead of 1).
So we retrieve the existing Product, and now comes the problem.
We don't have a "CategoryID" field on Product, we only have a Category property.
But we don't really want to retrieve the category (by id) just to assign it to the Product.
So I guess what I want to know is should we...
a) Add a CategoryID property to Product
b) Create a new category, assign it the relevant id and attach that to Product (but surely that will cause errors, or overwrite the existing category)
c) Retrieve (lookup) the category from the system (by id) and attach that to the Product
d) Do something else entirely!
It looks like you might be able to using the Session.Load(id) functionality.
Session.Load is a special method that returns a proxy with the ID until you request another property at which point it loads. It throws an error if there is no item matching the ID. Try something like:
product.Category = Session.Load<Category>(2); //2 being the new category ID
Session.SaveOrUpdate(product);
I just did a little testing and it did not seem to pull back the entire Category.
Updated: Session.Load is the correct answer
product.Category = session.Load<Category>(2);
session.Save(product);
Use NH's EnumStringType<T> to map your Category as an enum to the respective database value (which can be a string or a number). You'll find quite a few usage examples, if you google for it.
HTH!
Related
I installed an add-on for bulk action (called ba_importer v 1.1.24), I upload an Excel file with my data and create a group of products.
I can set the categories' tree or manually add ID of main categories and associated. I tried with no luck to use the tree features (like Home/Products/etc) and so I use all the ID of main category and all the associated. The result is a product with the correct categories set, but with no specific price from the customer group linked to a category.
I tried to edit a single product, remove all categories and set it one by one (set one, save, set one, save etc.) and then the specific price from the group linked to a category appears to the product.
Is there a better solution? I'm thinking about make a personal PHP page that reads an Excel file and sets all the information about the product, but I'm scared to face the same problem with the specific price.
There is no such thing as "category-related specific price",
if you have specific prices tied to customer groups , these are created as a result of the add/update product action with ps_specific_price DB entries having id_group with your restricted ID.
It is likely that the bulk module acts directly with DB queries to speed up things and bypasses this operation, I've seen this behaviour with those kind of modules in the past.
Since you are talking of a paid add-on, I would definitely seek help from the developer.
I need a new field inside Contact model that would hold information about Allowed companies of the related user.
Now there is only field about Currently picked company by that user (and it is not enough for me to make a record rule).
The field I want to copy values from is inside model Users and it is called company_ids.
I’m trying to add this field in the developer mode (Settings > Technical > Fields) like this:
But I’m having trouble with code that would fill my field with values from the another model.
for record in self:
record[("x_company_ids")] = env['res.users'].company_ids
I’m guessing that the record is referring to a record inside Contact model and it does not contain fields from another models like Users. So I can’t figure it out how to reference a field from another model.
Something similar to this: env['res.users'].company_ids?
It is even harder for me because it is many2many field and should always update when the source changes.
Maybe better solution would be to use Automatic action to write values to this field?
I saw some threads like this: Computed many2many field dependencies in Odoo 10.
But it seems like in those cases they had clear connection between the fields and I don't have it. I don't know how to get related user while I'm inside Contact model. I know only how to this oposite way (from user to contact): user.partner_id.id
Here in below given code you haven't specified related user from which you will get company_ids, you have directly accessing company_ids
for record in self:
record[("x_company_ids")] = env['res.users'].company_ids
You can write as following :
for record in self:
record["x_company_ids"] = self.env['res.users'].search([('partner_id','=',record.id)]).company_ids
In my web2py application I have a requirement to duplicate a record and all its references.
For example
one user has a product (sponserid is the user). and this product has so many features stored in other tables (reference to product id).
And my requirement is if an another user is copying this product, the a new record will generate in the product table with new productid and new sponserid. And all the reference table records will also duplicate with the new product id. Effectively a duplicate entry is creating in all the tables only change is product id and sponserid.
The product table fields will change. So I have to write a dynamic query.
If I can write a code like below
product = db(db.tbl_product.id==productid).select(db.tbl_product.ALL).first()
newproduct = db.tbl_product.insert(sponserid=newsponserid)
for field,value in product.iteritems():
if field!='sponserid':
db(db.tbl_product.id==newproduct).update(field=value)
But I cannot refer a field name like this in the update function.
Also I would like to know if there is any other better logic to achieve this requirement.
I would greatly appreciate any suggestions.
For the specific problem of using the .update() method when the field name is stored in a variable, you can do:
db(db.tbl_product.id==newproduct).update(**{field: value})
But an easier approach altogether would be something like this:
product = db(db.tbl_product.id==productid).select(db.tbl_product.ALL).first()
product.update(sponserid=newsponserid)
db.tbl_product.insert(**db.tbl_product._filter_fields(product))
The .update() method applied to the Row object updates only the Row object, not the original record in the db. The ._filter_fields() method of the table takes a record (Row, Storage, or plain dict) and returns a dict including only the fields that belong to the table (it also filters out the id field, which the db will auto-generate).
I've got a table in my database storing items:
Items
-------
ItemID
Name
...
Etc
and a separate table storing the PK of two different items from the first table. I want to be able to list the one item, and then any number of related items. I've tried searching for examples but haven't found much surprisingly...
RelatedItems
------------
ItemID
RelatedItemID
If I have four products, whose IDs are 1, 2, 3 and 4... and 1 is related to 2 and 3 I might have data that looks like this:
ItemID RelatedItemID
1 2
1 3
4 1
I am then modeling them in the Entity Framework Designer, and the designer automatically adds an association from the Items table to itself (many to many). The designer also adds two navigation properties, if I use the first property on Item #1 I get all items where Item #1 is in the first column, and if I use the second property I get all the items where Item #1 is in the second column.
I however just want to have one navigation property where I can say Items.RelatedItems and it returns all the items that the above two properties would when combined. I know I can join the two results after the fact but I can't help to think I'm doing something wrong and there is a better way.
Hopefully this is all clear enough.
It sounds like SQL schemas just aren't very good at modeling the concept you're looking for. The schema you've chosen would work well if you want to establish a directional relationship (item A is related to item B, but item B may or may not be related to item A). If you were looking for a grouping-style relationship (Items A and B are in the same group), I can think of a different approach you'd use. But I can't think of a good way to model an inherently bi-directional relationship using a traditional relational database.
Some workarounds might be to use a View that joins the two results, or to use triggers to make sure that every mapping from A to B has a corresponding mapping from B to A, so that both of the properties always return the same objects.
If you have an instance of an Item, call it item, then the following will give you the related items...
item.RelatedItems.Select(ri => ri.Item);
Your RelatedItems property on item (ie the first navigation property you mentioned) will be a collection of RelatedItem objects, each of which has two navigation properties of its own, one of which will be named Item and will be a link to the related item.
Note that this is air code, as I'm not in front of anything I can test this on right now, but I think this will do what you want.
If you want to make it simpler, you can write an extension method to wrap up the Select(), something like this...
public static IEnumerable<Item> RelItems(this Item item) {
return item.RelatedItems.Select(ri => ri.Item);
}
Then you could just do...
item.RelItems();
Note that I couldn't name the extension method RelatedItems, as that would clash with the navigation property that EF would have created for the second table. That's perhaps not a good name for that tables, as it's not the actual items, rather the IDs of the items. Either way, the above code should work.
According to the REST philosophy, a PUT request should update the resource at a URL if it exists, and create it if it doesn't exist. So in other words, if I use the following URL:
PUT http://server/item/5
If an Item exists with an ID of 5, it will be updated. If an Item doesn't exist with an ID of 5, a new Item will be created with an ID of 5.
However, I'm using NHibernate for persistence, and I mapped my IDs as Identity. This means that no matter what value I assign the ID, NHibernate will replace it with its own when I save a new Item.
How do I get NHibernate to save an Item with the ID that I assign it, without changing the ID mapping to Assigned?
If you use Identity, the DB won't allow you to enter a value.
That said, if your DB has some special syntax to allow inserting with explicit values in Identity fields, you can implement your own generator, which I guarantee will be error prone, hard to debug, and not very useful. But it's possible.
Study everything in https://nhibernate.svn.sourceforge.net/svnroot/nhibernate/trunk/nhibernate/src/NHibernate/Id and start creating your Frankenstein :-)