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Inserting data using Linq to SQL with foreign keys

I have a database that contains 'Personne' table, 'Patient' table (this one contains a foreign key to the id of 'Personne'), and 'RendezVous' table. i want to add a new element on my RendezVous table, but in my 'RendezVous' table i want the idPatient, and i am entering the first and last name in my app so i have to do a search on 'Personne' table to get the idPerson, and search that id on my 'Patient' table to get it the idPatient. If the patient doesn't exist, i put the id on 1. I'm using LinQ to SQL, but it doesn't work... Can i get some help?
public void AddRdv(DateTime date, byte idMedecin, string nomPatient, string prenomPatient, bool important, string notes)
{
string con = $#"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename={System.IO.Path.GetDirectoryName(Assembly.GetEntryAssembly().Location)}\MCDatabase.mdf;Integrated Security=True";
MCDataClassDataContext dataClass = new MCDataClassDataContext(con);
var patientRdv = (from personne in dataClass.Personne
where nomPatient == personne.nom && prenomPatient == personne.prenom
join patient in dataClass.Patient on personne.Id equals patient.IdPersonne
select personne);
Personne pers=patientRdv.First();
if (patientRdv.Count()!=0)
{
pers = patientRdv.First();
RendezVous rdv = new RendezVous
{
Date = date,
IdPatient = pers.Id,
IdMedecin = idMedecin,
Important = important,
Fait = false,
Note = notes
};
dataClass.RendezVous.InsertOnSubmit(rdv);
dataClass.SubmitChanges();
}
else
{
RendezVous rdv = new RendezVous
{
Date = date,
IdPatient = 1,
IdMedecin = idMedecin,
Important = important,
Fait = false,
Note = notes
};
dataClass.RendezVous.InsertOnSubmit(rdv);
dataClass.SubmitChanges();
}
}

Dapper One To Many Relationship

I have 3 tables structured in the following way:
CREATE TABLE [User](
Id int NOT NULL,
Name varchar(50)
PRIMARY KEY (Id)
)
CREATE TABLE [Role](
Id int NOT NULL,
UserId int NOT NULL,
Name varchar(50),
PRIMARY KEY (Id),
FOREIGN KEY (UserId) REFERENCES [User](Id)
)
CREATE TABLE [Description](
Id int NOT NULL,
RoleId int NOT NULL,
Name varchar(50)
FOREIGN KEY (RoleId) REFERENCES [Role](Id)
)
As you can see it is one to many relationship nested twice. In the code I have the following classes to represent them:
public class User
{
public int Id { get; set; }
public string Name { get; set; }
public IEnumerable<Role> Roles { get; set; }
}
public class Role
{
public int Id { get; set; }
public int UserId { get; set; }
public string Name { get; set; }
public IEnumerable<Description> Descriptions { get; set; }
}
public class Description
{
public int Id { get; set; }
public int RoleId { get; set; }
public string Name { get; set; }
}
Now I need to query for the user and also get all fields that come with it. I have figured out a way to do that using QueryMultiple such as this:
var queryOne = "SELECT Id, Name FROM [User] WHERE Id = 1";
var queryTwo = "SELECT r.Id, r.UserId, r.Name FROM [User] u INNER JOIN [Role] r ON u.Id = r.UserId WHERE u.Id = 1";
var queryThree = "SELECT d.Id, d.RoleId, d.Name FROM [User] u INNER JOIN [Role] r ON u.Id = r.UserId INNER JOIN [Description] d ON r.Id = d.RoleId WHERE u.Id = 1";
var conn = new SqlConnection();
using (var con = conn)
{
var result = con.QueryMultiple(queryOne + " " + queryTwo + " " + queryThree);
var users = result.Read<User>().FirstOrDefault();
var roles = result.Read<Role>();
var descriptions = result.Read<Description>();
if (users != null && roles != null)
{
users.Roles = roles;
Console.WriteLine("User: " + users.Name);
foreach (var role in users.Roles)
{
Console.WriteLine("Role: " + role.Name);
if (descriptions != null)
{
role.Descriptions = descriptions.Where(d => d.RoleId == role.Id);
foreach (var roleDescription in role.Descriptions)
{
Console.WriteLine("Description: " + roleDescription.Name);
}
}
}
}
}
The result is:
User: Bob
Role: Tester
Description: Tester First Description
Description: Tester Second Description
Description: Tester Third Description
Role: Manager
Description: Manager First Description
Description: Manager Second Description
Description: Manager Third Description
Role: Programmer
Description: Programmer First Description
Description: Programmer Second Description
Description: Programmer Third Description
Main Question:
While the above code works it feels too messy. I was wondering if there is a better/easier way to achieve this?
Bonus Points:
Please also feel free to suggest a better way to query this than using inner joins. My goal is to improve performance.
EDIT:
I came up with option two as well, but again I don't think its a good solution. With option 2 I create a 4th object that will contain results of the 3 objects combined such as this:
public class Combination
{
public int UserId { get; set; }
public string UserName { get; set; }
public int RoleId { get; set; }
public string RoleName { get; set; }
public int DescriptionId { get; set; }
public string DescriptionName { get; set; }
}
Then I process it like this:
var queryFour = "SELECT u.Id as 'UserId', u.Name as 'UserName', r.Id as 'RoleId', r.Name as 'RoleName', d.Id as 'DescriptionId', d.Name as 'DescriptionName' FROM [User] u INNER JOIN [Role] r ON u.Id = r.UserId INNER JOIN [Description] d ON r.Id = d.RoleId WHERE u.Id = 1";
var conn = new SqlConnection();
using (var con = conn)
{
var myUser = new User();
var result = con.Query<Combination>(queryFour);
if (result != null)
{
var user = result.FirstOrDefault();
myUser.Id = user.UserId;
myUser.Name = user.UserName;
var roles = result.GroupBy(x => x.RoleId).Select(x => x.FirstOrDefault());
var myRoles = new List<Role>();
if (roles != null)
{
foreach (var role in roles)
{
var myRole = new Role
{
Id = role.RoleId,
Name = role.RoleName
};
var descriptions = result.Where(x => x.RoleId == myRole.Id);
var descList = new List<Description>();
foreach (var description in descriptions)
{
var desc = new Description
{
Id = description.DescriptionId,
RoleId = description.RoleId,
Name = description.DescriptionName
};
descList.Add(desc);
}
myRole.Descriptions = descList;
myRoles.Add(myRole);
}
}
myUser.Roles = myRoles;
}
Console.WriteLine("User: " + myUser.Name);
foreach (var myUserRole in myUser.Roles)
{
Console.WriteLine("Role: " + myUserRole.Name);
foreach (var description in myUserRole.Descriptions)
{
Console.WriteLine("Description: " + description.Name);
}
}
}
The resulting output is the same in both methods and the second method uses 1 query as opposed to 3.
EDIT 2: Something to consider, my data for these 3 tables are updated often.
EDIT 3:
private static void SqlTest()
{
using (IDbConnection connection = new SqlConnection())
{
var queryOne = "SELECT Id FROM [TestTable] With(nolock) WHERE Id = 1";
var queryTwo = "SELECT B.Id, B.TestTableId FROM [TestTable] A With(nolock) INNER JOIN [TestTable2] B With(nolock) ON A.Id = B.TestTableId WHERE A.Id = 1";
var queryThree = "SELECT C.Id, C.TestTable2Id FROM [TestTable3] C With(nolock) INNER JOIN [TestTable2] B With(nolock) ON B.Id = C.TestTable2Id INNER JOIN [TestTable] A With(nolock) ON A.Id = B.TestTableId WHERE A.Id = 1";
var gridReader = connection.QueryMultiple(queryOne + " " + queryTwo + " " + queryThree);
var user = gridReader.Read<Class1>().FirstOrDefault();
var roles = gridReader.Read<Class2>().ToList();
var descriptions = gridReader.Read<Class3>().ToLookup(d => d.Id);
user.Roles= roles;
user.Roles.ForEach(r => r.Properties = descriptions[r.Id].ToList());
}
}

Your first option can be simplified to the following. It removes the deep control structure nesting. You can generalize it to deeper nesting without adding more nesting/complexity.
var queryOne = "SELECT Id, Name FROM [User] WHERE Id = 1";
var queryTwo = "SELECT r.Id, r.UserId, r.Name FROM [User] u INNER JOIN [Role] r ON u.Id = r.UserId WHERE u.Id = 1";
var queryThree = "SELECT d.Id, d.RoleId, d.Name FROM [User] u INNER JOIN [Role] r ON u.Id = r.UserId INNER JOIN [Description] d ON r.Id = d.RoleId WHERE u.Id = 1";
var conn = new SqlConnection();
using (var con = conn)
{
var gridReader = con.QueryMultiple(queryOne + " " + queryTwo + " " + queryThree);
var user = gridReader.Read<User>().FirstOrDefault();
if (user == null)
{
return;
}
var roles = gridReader.Read<Role>().ToList();
var descriptions = gridReader.Read<Description>().ToLookup(d => d.RoleId);
user.Roles = roles;
roles.ForEach(r => r.Descriptions = descriptions[r.Id]);
}
Performance-wise it behaves the same as your first option.
I would't go with your second option (or the similar view based one): in case you have R roles, and on average D descriptions per roles, you would query 6*R*D cells instead of 2+3*R+3*D. If R and D are high, you'd be querying a lot more data, and the cost of deserialization will be to high compared to running 3 queries instead of 1.

An alternative approach (Working code snippet with .Net Core):
Why not create a database View like this -
create view myview
As
SELECT u.Id as 'UserId', u.Name as 'UserName', r.Id as 'RoleId',
r.Name as 'RoleName', d.Id as 'DescriptionId', d.Name as 'DescriptionName'
FROM User u INNER JOIN Role r ON u.Id = r.UserId
INNER JOIN Description d ON r.Id = d.RoleId;
Then you can use your cleaner query as below :
public List<Combination> GetData(int userId)
{
String query = "select * from myview" + " where userId = " + userId + ";";
using (System.Data.Common.DbConnection _Connection = database.Connection)
{
_Connection.Open();
return _Connection.Query<Combination>(query).ToList();
}
}
And your processing code will look like this :
[Note: This can be enhanced even further.]
public static void process (List<Combination> list)
{
User myUser = new User(); myUser.Id = list[0].UserId; myUser.Name = list[0].UserName;
var myroles = new List<Role>(); var r = new Role(); string currentRole = list[0].RoleName;
var descList = new List<Description>(); var d = new Description();
// All stuff done in a single loop.
foreach (var v in list)
{
d = new Description() { Id = v.DescriptionId, RoleId = v.RoleId, Name = v.DescriptionName };
if (currentRole == v.RoleName)
{
r = new Role() { Id = v.RoleId, Name = v.RoleName, UserId = v.UserId, Descriptions = descList };
descList.Add(d);
}
else
{
myroles.Add(r);
descList = new List<Description>(); descList.Add(d);
currentRole = v.RoleName;
}
}
myroles.Add(r);
myUser.Roles = myroles;
Console.WriteLine("User: " + myUser.Name);
foreach (var myUserRole in myUser.Roles)
{
Console.WriteLine("Role: " + myUserRole.Name);
foreach (var description in myUserRole.Descriptions)
{
Console.WriteLine("Description: " + description.Name);
}
}
}
From the performance standpoint, Inner Joins are better than other forms of query like subquery, Co-related subquery, etc. But ultimately everything boils down to the SQL execution plan.

The tl;dr of my answer to you:
Abstract. You should break-up things into the different jobs they do. C# gives you functions and classes, they can help clean up code a lot.
If you can look at a chunk of code and say "this chunk is basically taking something and doing blah with it to get some result..", then make a function called SomeResult DoBlah(SomeThing thing)
Don't let a little more code scare you, it may make the big picture seem more complex at first glance. But it will make small chunks of code way easier to understand, and that makes the big picture easier to understand.
My full answer:
There are a couple of things you could do that would make this cleaner. Probably the biggest thing you could do for yourself, is to separate out some of the responsibilities/concerns. You have a lot of different things going on, and all of it is in one place, relying on everything staying exactly like it is, forever. If you change something, you will have to change things all over the place to make sure everything works. This is called "coupling", and coupling is bad... um-kay.
At the broadest level, you have three different things going on: 1. You are trying to apply logic to users and roles (i.e. You want to get info on all of the users in a role.) 2. You are trying to pull info from a database, and fit it into User, Role, and Description objects. 3. You are trying to display information about Users, Roles, and Descriptions.
So if I were you, I would have at least 3 classes right there. \
Program that is the driver of your application. It should have a main function and should use the other 3 classes.
DisplayManager that can be responsible for writing info out to a console. It should be constructed with an IEnumerable<User> and should have a public method public void DisplayInfo() that will write its list of users to a console.
UserDataAccess that can be used for fetching a list of users from a database. I would have it expose a public method for public IEnumerable<User> GetUsersByRoleID(int roleID)
This way, your main program would look something like this:
public static void Main(String[] args)
{
int roleID = 6;
UserDataAccess dataAccess = new UserDataAccess();
IEnumerable<User> usersInRole = dataAccess.GetUsersByRoleID(roleID);
DisplayManager displayManager = new DisplayManager(usersInRole);
displayManager.DisplayInfo();
}
Honestly, this is a simplified version of what I would do if the problem had more functionality then just getting a single specific piece of info. You should look into SOLID principles. Specifically "Single Responsibility" and "Dependency Inversion", these principles can really clean up some "messy"/"smelly" code.
Next, as far as your actually data access goes, since you are using dapper, you should be able to map nested objects using build in dapper functionality. I believe this link should be of some help to you in this aspect.

Parameterize DocumentDB query with IN clause

I have a query somewhat like the following which I'm trying to parameterize:
List<string> poiIDs = /*List of poi ids*/;
List<string> parameterNames = /*List of parameter names*/;
string inClause = string.Join(",", parameterNames);
string query = string.Format("SELECT c.id AS poiID, c.poiName, c.latitude, c.longitude FROM c WHERE c.clusterName = #clusterName AND c.id IN ({0}) AND c.deleted = false", inClause);
IQueryable<POI> queryResult = Client.CreateDocumentQuery<POI>(Collection.SelfLink, new SqlQuerySpec
{
QueryText = query,
Parameters = new SqlParameterCollection()
{
new SqlParameter("#clusterName", "POI"),
// How do I declare the dynamically generated parameters here
// as new SqlParameter()?
}
});
How do I declare the dynamically generated parameters as new SqlParameter() for the Parameters property of SqlQuerySpec in order to create my document query?

You can create dynamic parameterized query like this:
// DocumentDB query
// POINT TO PONDER: create the formatted query, so that after creating the dynamic query we'll replace it with dynamically created "SQL Parameter/s"
var queryText = #"SELECT
us.id,
us.email,
us.status,
us.role
FROM user us
WHERE us.status = #userStatus AND us.email IN ({0})";
// contain's list of emails
IList<string> emailIds = new List<string>();
emailIds.Add("a#gmail.com");
emailIds.Add("b#gmail.com");
#region Prepare the query
// simple parameter: e.g. check the user status
var userStatus = "active";
var sqlParameterCollection = new SqlParameterCollection { new SqlParameter("#userStatus", userStatus) };
// IN clause: with list of parameters:
// first: use a list (or array) of string, to keep the names of parameter
// second: loop through the list of input parameters ()
var namedParameters = new List<string>();
var loopIndex = 0;
foreach (var email in emailIds)
{
var paramName = "#namedParam_" + loopIndex;
namedParameters.Add(paramName);
var newSqlParamter = new SqlParameter(paramName, email);
sqlParameterCollection.Add(newSqlParamter);
loopIndex++;
}
// now format the query, pass the list of parameter into that
if (namedParameters.Count > 0)
queryText = string.Format(queryText, string.Join(" , ", namedParameters));
// after this step your query is something like this
// SELECT
// us.id,
// us.email,
// us.status,
// us.role
// FROM user us
// WHERE us.status = #userStatus AND us.email IN (#namedParam_0, #namedParam_1, #namedParam_2)
#endregion //Prepare the query
// now inject the parameter collection object & query
var users = Client.CreateDocumentQuery<Users>(CollectionUri, new SqlQuerySpec
{
QueryText = queryText,
Parameters = sqlParameterCollection
}).ToList();

The following gives you a SQL query, you can then run in your DocumentDB Collection, to get the Documents by their IDs.
var query = $"SELECT * FROM p WHERE p.id IN ('{string.Join("', '", arrayOfIds)}')";

The DocumentDB SDK doesn't support parameterized IN queries.
Judging from the SO thread in the comment above, SQL does not either. As mentioned in the other thread, you can use LINQ as a workaround.

Why not use the ArrayContains method? Here is an example in node
sqlQuery = {
query: 'SELECT * FROM t WHERE ARRAY_CONTAINS(#idList, t.id)',
parameters: [
{
name: '#idList',
value: ['id1','id2','id3'],
},
],
};

Join and order in LINQ C#

I have been given the following skeleton code:
var test = SqlCompact(
"OrderID", "ASC", 5, 2,
out count, out sortCriteria, out sql);
This calls the SqlCompact method which performs joins of tables orders, employees and customers & then orders by the inputs e.g. "ASC" and "Column Name".
I have got the join query working but not sure how to order the results according to the input. This is my code for SqlCompact Method:
public List<MyJoin> SqlCompact(
string sort, string sortDir, int rowsPerPage, int page,
out int count, out string sortCriteria, out string sql) {
var cec = new SqlCeConnection(
string.Format(#"Data Source={0}\Northwind.sdf", Path));
var nwd = new DataContext(cec);
nwd.Log = new StringWriter();
var orders = nwd.GetTable<Order>();
var employees = nwd.GetTable<Employee>(); //
var customers = nwd.GetTable<Customer>(); //
count = orders.Count();
sortCriteria = "";
var q = (from od in orders
join em in employees on od.EmployeeID equals em.EmployeeID
join ct in customers on od.CustomerID equals ct.CustomerID
//orderby em.EmployeeID
select new
{
od.OrderID,
od.ShipCountry,
ct.CompanyName,
ct.ContactName,
FullName = em.FirstName + ' '+ em.LastName,
}).ToList();
q.Dump();
sortCriteria: a string composed from sort and sortDir – in the format directly usable by Dynamic LINQ, e.g.
OrderID ASC
ContactName DESC, OrderID DESC

This is what you want to do:
if (sort == "OrderId") {
q = q.OrderBy(x => x.OrderId);
}
Passing in the the column name as a string is not a great way to do it though.

Concat or Join list of "names" in Linq

Using WCF RIA I have a query that returns a Query of names
public class WitnessInfo
{
[Key]
public Guid WCFId { get; set; }
public string witnessName { get; set; }
public string AllNames {get; set;}
}
Here's my Linq Query
[Query]
public IQueryable<WitnessInfo> getWitnessInfo(int? id)
{
IQueryable<WitnessInfo> witnessQuery = from witness in this.Context.witness
where witness.DAFile.Id == id
select new WitnessInfo
{
WCFId = Guid.NewGuid(),
witnessName = witness.Person.FirstName,
};
return witnessQuery;
}
I want to take all the names and return them in a single string i.e "John, James, Tim, Jones". Tried taking AllNames and looping through but that didn't work. Any suggestions?

First grab all of the information that you need in a single query, then use String.Join to map the collection of names to a single string:
var firstQuery = from witness in Context.witness
where witness.DAFile.Id == id
select new
{
WCFId = Guid.NewGuid(),
witnessName = witness.Person.FirstName,
Names = Context.witness.Select(w => w.FirstName),
})
.AsEnumerable(); //do the rest in linq to objects
var finalQuery = from witness in firstQuery
//do the string manipulation just once
let allNames = string.Join(", ", witness.Names)
select new WitnessInfo
{
WCFId = witness.WCFId,
witnessName = witness.witnessName,
AllNames = allNames,
});

By having the AllNames property in the WitnessInfo class, it is seems like you want each WitnessInfo object to contain the all of the squence names again and again repeatedly, and if this is your case then do it like that:
var names = (from witness in this.Context.witness
select witness.Person.FirstName).ToArray();
var allNames = string.Join(", ", names);
IQueryable<WitnessInfo> witnessQuery = from witness in this.Context.witness
where witness.DAFile.Id == id
select new WitnessInfo
{
WCFId = Guid.NewGuid(),
witnessName = witness.Person.FirstName,
AllNames = allNames
};

You can concatenate like this:
string.Join(", ", getWithnessInfo(666).Select(wq => wq.witnessName))

this.Context.witness.Select(a => a.Person.Firstname).Aggregate((a, b) => a + ", " + b);