public static Employee FindById(object key)
{
var context = new SoftUniEntities();
var findEmployeeByKey = context.Employees.Find(key);
return(findEmployeeByKey);
}
public static void Add(Employee employee)
{
var context = new SoftUniEntities();
context.Employees.Add(employee);
context.SaveChanges();
}
public static void Delete(Employee employee)
{
var context = new SoftUniEntities();
var getId = context.Employees.Find(employee.EmployeeID);
context.Employees.Remove(getId);
context.SaveChanges();
}
public static void Modify(Employee employee, string newName)
{
var context = new SoftUniEntities();
var getId = context.Employees.Find(employee.EmployeeID);
getId.FirstName = newName;
context.SaveChanges();
}
static void Main()
{
/* Problem 2. Employee DAO Class */
//Add(new Employee()
//{
// FirstName = "Beni",
// LastName = "Nataniahu",
// JobTitle = "Manager",
// DepartmentID = 2,
// HireDate = DateTime.Now,
// Salary = 10000
//});
//var employee = FindById(1);
//Console.WriteLine(employee.EmployeeID + " " + employee.FirstName + " " + employee.LastName);
//Modify(new Employee(){EmployeeID = 3}, "Simeon");
//Delete(new Employee() { EmployeeID = 294 });
/* Problem 3. Database Search Queries */
/* 1. Find all employees who have projects started in the time period 2001 - 2003 (inclusive).
* Select each employee's first name, last name and manager name
* and each of their projects' name, start date, end date. */
var context = new SoftUniEntities();
var employees = from e in context.Employees
from p in e.Projects
join m in context.Employees on e.ManagerID equals m.EmployeeID
orderby e.FirstName
select new
{
EmployeeFirstName = e.FirstName,
EmployeeLastName = e.LastName,
ManagerFirstName = m.FirstName,
ManagerLastName = m.LastName,
ProjectName = p.Name,
ProjectStartDate = p.StartDate,
ProjectEndDate = p.EndDate
};
var empoyeesB = context.Employees
.Join(context.Employees,
e => e.ManagerID,
m => m.EmployeeID,
(e, m) => new
{
FirstName = e.FirstName,
LastName = e.LastName,
Project = e.Projects.Select(p => p.Name),
Mananager = m.FirstName + " " + m.LastName
})
.OrderBy(e => e.FirstName)
.ToList();
//foreach (var em in empoyeesB)
//{
// Console.WriteLine(em.FirstName + em.LastName + " - " + em.Mananager);
//}
//foreach (var employee in employees)
//{
// Console.WriteLine("{0} {1} - Manager: {2} {3}\n Projetc name: {4}\n Start: {5}\n End: {6}",
// employee.EmployeeFirstName,
// employee.EmployeeLastName,
// employee.ManagerFirstName,
// employee.ManagerLastName,
// employee.ProjectName,
// employee.ProjectStartDate,
// employee.ProjectEndDate);
//}
/* 2. Find all addresses,
* ordered by the number of employees who live there (descending),
* then by town name (ascending).
* Take only the first 10 addresses and select their address text, town name and employee count. */
var addresses = context.Addresses
.OrderByDescending(a => a.Employees.Count)
.ThenBy(a => a.Town.Name)
.Take(10)
.Select(a => new
{
a.AddressText,
a.Town.Name,
a.Employees.Count
});
//foreach (var address in addresses)
//{
// Console.WriteLine("{0}, {1} - {2} employees",
// address.AddressText,
// address.Name,
// address.Count);
//}
/* 3. Get an employee by id (e.g. 147).
* Select only his/her first name, last name, job title and projects (only their names).
* The projects should be ordered by name (ascending).*/
// Variant 1
var employeeById = from e in context.Employees
from p in e.Projects
where e.EmployeeID == 147
orderby p.Name
select new
{
e.FirstName,
e.LastName,
e.JobTitle,
p.Name
};
//foreach (var employee in employeeById)
//{
// Console.WriteLine("{0} {1} - {2} ({3})",
// employee.FirstName,
// employee.LastName,
// employee.JobTitle,
// employee.Name);
//}
// Variant 2
var getEmployee = from e in context.Employees
where e.EmployeeID == 147
select new
{
FirstName = e.FirstName,
LastName = e.LastName,
JobTitle = e.JobTitle,
ProjectName = e.Projects.Select(p => p.Name)
};
//foreach (var employee in getEmployee)
//{
// Console.WriteLine("{0} {1} ({2})",
// employee.FirstName,
// employee.LastName,
// employee.JobTitle);
// foreach (var projetcs in employee.ProjectName)
// {
// Console.WriteLine("Projetc: " + projetcs);
// }
//}
/* 4. Find all departments with more than 5 employees.
* Order them by employee count (ascending).
* Select the department name, manager name and first name, last name,
* hire date and job title of every employee. */
// Variant 1
var deparmentsA = from d in context.Departments
join e in context.Employees on d.ManagerID equals e.EmployeeID
join w in context.Employees on d.DepartmentID equals w.DepartmentID
where d.Employees.Count > 5
group d by new
{
d.Name,
e.LastName,
d.Employees.Count
} into g
orderby g.Key.Count
select new
{
DepartmenName = g.Key.Name,
ManagerName = g.Key.LastName,
Employees = g.Key.Count
};
//Console.WriteLine(deparmentsA.Count());
//foreach (var department in deparmentsA)
//{
// Console.WriteLine("--{0} - Manager: {1}, Employees: {2}",
// department.DepartmenName,
// department.ManagerName,
// department.Employees);
//}
// Varinat 2
var departmentsB = from d in context.Departments
join e in context.Employees on d.ManagerID equals e.EmployeeID
join w in context.Employees on d.DepartmentID equals w.DepartmentID
where d.Employees.Count > 5
group d by new
{
DepartmentName = d.Name,
ManagerName = e.FirstName + " " + e.LastName,
EmployeeName = w.FirstName + " " + w.LastName,
HireDate = w.HireDate,
JobTitle = w.JobTitle,
Count = d.Employees.Count
} into g
orderby g.Key.Count
select g;
//foreach (var department in departmentsB)
//{
// Console.WriteLine("--{0} - Manager: {1}, Employees: {2}, Hire date: {3}, Job title: {4}",
// department.Key.DepartmentName,
// department.Key.ManagerName,
// department.Key.EmployeeName,
// department.Key.HireDate,
// department.Key.JobTitle);
//}
/* Problem 4. Native SQL Query */
var sw = new Stopwatch();
sw.Start();
const string nativeQ = "SELECT FirstName FROM Employees e " +
"JOIN EmployeesProjects ep ON ep.EmployeeID = e.EmployeeID " +
"JOIN Projects p ON p.ProjectID = ep.ProjectID " +
"WHERE YEAR(p.StartDate) = {0}";
var employeesQ = context.Database.SqlQuery <string>(nativeQ, "2002");
//foreach (var employee in employeesQ)
//{
// Console.WriteLine(employee);
//}
//Console.WriteLine("Native: {0}", sw.Elapsed);
//sw.Restart();
var linqA = from e in context.Employees
from p in e.Projects
where p.StartDate.Year == 2002
select e.FirstName;
//foreach (var lA in linqA)
//{
// Console.WriteLine(lA);
//}
//Console.WriteLine("Linq: {0}", sw.Elapsed);
//sw.Restart();
var linqB = context.Projects
.Where(p => p.StartDate.Year == 2002)
.SelectMany(e => e.Employees)
.Select(e => e.FirstName);
//foreach (var lB in linqB)
//{
// Console.WriteLine(lB);
//}
//Console.WriteLine("Linq: {0}", sw.Elapsed);
/* Problem 5. Concurrent Database Changes with EF */
//using (var contextA = new SoftUniEntities())
//{
// var changeA = contextA.Employees.First();
// changeA.FirstName = "Simu";
// using (var contextB = new SoftUniEntities())
// {
// var changeB = contextB.Employees.First();
// changeB.FirstName = "Tosho";
// contextB.SaveChanges();
// }
// contextA.SaveChanges();
//}
/* Problem 6. Call a Stored Procedure */
var allProjects = context.FindProjects("JoLynn", "Dobney");
// foreach (var project in allProjects)
// {
// Console.WriteLine(project.ProjetcName + " - " + project.Description + " Start: " + project.StartDate);
// }
}
