cross-database

问题 I have two entities Entity1 and Entity2 with a OneToMany relation, but they live in two MySQL databases. How can I implement those entities with their relation in Symfony? Is it possible to create two separated bundles where to implement those entities? 回答1: In Doctrine, joining data across databases is not technically “supported” by a designed feature, but you can make it work by tricking Doctrine a little bit. If you want to build a relationship between entities then they must use the same

问题 This my model of first Database DB1: from django.db import models class Company(models.Model): name = models.CharField(max_length=100, null=True) address = models.TextField(max_length=200, null=True) website = models.CharField(max_length=200, null=True) conatct_no = models.CharField(max_length=20, null=True) email = models.EmailField(max_length=20, null=True) logo = models.FileField(upload_to='logo/', blank=True, null=True) created = models.DateTimeField('company created', auto_now_add=True)

问题 I'm trying to use Doctrine 2 in a ZF2 application which contains two modules, each with its own database. I need to use cross-database joins so that I can associate entities from one module with entities in another. Here's a UML diagram of the setup. I've tried using this in my first entity (I've removed irrelevant parameters and use statements): namespace Client\Entity; /** * A website. * * @ORM\Entity * @ORM\Table(name="users.website") * ... * @property $server */ class Website extends

问题 This question already has answers here : Possible to perform cross-database queries with PostgreSQL? (8 answers) Closed 5 years ago . I am trying to build a query in Postgres. My background is in SQL Server so, I'm having some syntactical challenges. My query needs to hit two seperate databases on two separate servers. I need to do a join between the datasets. Essentially, I have a table with user login activity in db1. A entry gets added each time a user logs into the website. On db2, I have

问题 I need to fetch records from tables, that are in two diff. databases in two different SQL Servers. For Instance. Sales DB on server1 and Purchase DB on server2. Both Sales and Purchase DB's have some set of tables say table1 in Sales DB and table2 in Purchase DB. Now, I need to get records from table1 and table2 that are having some common records by joining them. Using T-SQL i can do it by linking the servers and then quering them. Please suggest, how can i do it using LINQ to SQL as am'nt

问题 I need to fetch records from tables, that are in two diff. databases in two different SQL Servers. For Instance. Sales DB on server1 and Purchase DB on server2. Both Sales and Purchase DB's have some set of tables say table1 in Sales DB and table2 in Purchase DB. Now, I need to get records from table1 and table2 that are having some common records by joining them. Using T-SQL i can do it by linking the servers and then quering them. Please suggest, how can i do it using LINQ to SQL as am'nt

问题 Is it possible to do cross database table joins in JPA? I have a users table in one database which has a foreign key to a organizations table in a separate database. Both the databases are on same physical machine. Now MySQL allows me to write queries which span across multiple databases, but I am not sure how to do this with JPA. The @Entity annotations on the Java POJO's don't take the name of the database so there is no way to mark a cross DB relationship. Is there a workaround for this

问题 I was wondering if EF4 support cross-databse relationships? For instance: db1 Author Id Name db2 Posts Id Content db1.Author.Id What ideally I need to do to get this relation in my ef4 model? Do you guys have any idea? Thanks 回答1: I've found this entry in Microsoft Connect that answers the question about the support given at this moment by EF (actually it is not supported yet). Also found a thread in Social MSDN about this concern. Other links on Stack Overflow: ADO.Net Entity Framework

问题 Is there any way to implement cross database querying in Entity Framework? Let's imagine I've two Entities User and Post, User entity is in database1 and Post is in database2, which means those entities are in separate databases. How should I get user's posts in Entity Framework ? 回答1: EF context does not support cross database queries. You need to expose posts in database1 through SQL View (or synonym) and use it as part of that database. 回答2: I know this is an old question, but this is

问题 I'm importing data between two different database(which have not the same context). So I've two different context. The goal is to import some data of the context A to the context B. Data in the context B are never directly edited, they are only imported from the context A. In the context B, I've in copy the ID from which it has been imported. Now I'm trying to retrieve a list all data which aren't in the context B or have a more recent version. I've a ModifiedAt" field in the two table,