I am using sails framework to fetch data from a table and show it to the user, after some manupulations. The table belongs to another application, I just need to read the data from it.
I created a Model same as its available in the database along with the column names. I get an error as
RequestError: There is already an object named 'table_Name' in the database.
I cannot create table, is there a way around in sails
Related
I have a legacy (old) table with data in a database. Currently, data is put along with ids, so ids are not generated. I'm going to change a source of data. Data from a new source have other ids. These could clash with ids from the legacy table. So I don't want to use them. I'm going to map this data without ids and generate ids with jpa. Will it work if I change my entity for auto-generation and the id column to auto increment? Which options do I have otherwise?
My database looks like this: Database Diagram MSSMS
So everytime i'm adding a fish to the database, i want to add the fishes's continent, waterlagen and verbanden.
Tables Continenten, Waterlagen & Verbanden are already filled with objects from an array after creating the database.
Im using List Continenten; for example to store multiple continents.
So i tryed:
Vis nieuweVis = new Fish();
nieuweVis.Naam = "Molly";
foreach(Continent c in Continenten)
nieuweVis.Continenten.Add(c)
so in the table VisContinenten
i assume that EF will automaticly fill in the FishId and ContinentId wich are foreignkeys.
I want records in that table also to be unique so i add a unique key to both the columns in VisContinenten so that fish 1 on continent 1 won't appear twice in that table.
Error i get:
An error occurred while saving entities that do not expose foreign key
properties for their relationships
Additional information: Unable to update the EntitySet 'VisContinenten' because it has a DefiningQuery and no element exists in the element to support the current operation.
Help me pls :)
Thank you
I have two entities: one based on normal DB table and another base on DB View. They are connected one to many, like this:
Entity City do not have store procedures mapped because for entity Country it is enough to have read only collection of Cities.
And cascade rule is not set.
But then I want to delete Country instance which have some Cities loaded I've received the following error:
Unable to update the EntitySet because it has a
DefiningQuery and no 'DeleteFunction' element exists in the
'ModificationFunctionMapping' element to support the current
operation.
Which forcing me to create dummy stored procedure on DB and use it as Delete function, but it is an ugly solution.
Is there any better solution?
I have some dynamically created tables(using native queries). So I do not have the names in my entity but stored in a db table. Now I want to retrieve datas from each. I want to use only JPA.
To use JPA you must have Entity that maps on to any table that you want to access. If you don't have that then JPA is not for you, and just use JDBC. Can't get simpler.
I'm just starting out with the Entity Framework and ADO.NET Data Services and I've run into an issue that I can't seem to figure out. I have two tables, one that has user information and the other that has a created by field. Within the database, there isn't a foreign key between these tables. The user table contains an arbitrary Id, a username, and a display name. The created by field contains the user's username. In my entity I would like to have the user's display name since this is what I need to display and expose over the ADO.NET Data Service? I'm aware that I could restructure the database, but I was hoping that I could do the join using the username as I would in a SQL statement.
Thanks in advance,
-Damien
You can make a view using a join of both tables, and then use this object to display the user's name.
There's some info on mapping custom queries here.