Create table with Linq to Sqlite (linq2db)

问题

What I'm trying to do is to create a table on the fly, when a connection is opened on an empty database. I've already created the model with Linq to Sqlite and successfully used it with non-empty databases.

Now I'm trying to work with "new" databases.

I do my db.Insert like this:

    using (MyDB db = MyDB("MyConnectionName"))
    {
            Person d = new Person()
            {
                name = "mimi"
            };

            db.Insert(d);

            myLabel.Content = db.Drivers.First().name;
        }
    }

An empty database is opened OK. Actually a 0KB file is created for it. But when I try to insert something into it (or of course read something) I get an exception: SQL logic error or missing database

The library I'm using:

https://github.com/linq2db/linq2db

The NuGet package:

http://nuget.org/packages/linq2db.SQLite/

Is there something I need to do before start writing to an empty database file?

回答1:

Linq2DB doesn't create tables automatically. So you have to check whether table exists and if not-create it. You can do it this way:

    var sp = db.DataProvider.GetSchemaProvider();
    var dbSchema = sp.GetSchema(db);
    if(!dbSchema.Tables.Any(t => t.TableName == "Person"))
    {
       //no required table-create it
       db.CreateTable<Person>();
    }

Unfortunately there is some lack of documentation. But you can use test sample.

回答2:

I hope it helps - LINQ CRUD Operations

回答3:

you don't open the database.

MyDB db = MyDB("MyConnectionName") <- Create Database.

db.open(); <- add this.

then you will operate ordinarily.

来源：https://stackoverflow.com/questions/16853475/create-table-with-linq-to-sqlite-linq2db

标签

linq

sqlite

linq2db