static void Main(string[] args)
{
Console.WriteLine("Proceso iniciado.");
try
{
var dbContext = new PlutoContext();
}
catch (Exception ex)
{
Console.WriteLine("Error:");
Console.WriteLine(ex.Message);
Console.ReadLine();
}
Console.WriteLine("Proceso terminado.");
Console.ReadLine();
}
static void Main(string[] args)
{
Console.WriteLine("Proceso iniciado.");
try
{
var dbContext = new PlutoContext();
//LINQ Syntax
var query =
from c in dbContext.Courses
where c.Name.Contains("c#")
orderby c.Name
select c;
Console.WriteLine("LINQ Sintax Results;");
foreach (var course in query)
{
Console.WriteLine($"Course name: {course.Name}");
}
//Extension Methods
var query2 = dbContext.Courses
.Where(c => c.Name.Contains("c#"))
.OrderBy(c => c.Name);
Console.WriteLine("Extension Methods Results;");
foreach (var course in query2)
{
Console.WriteLine($"Course name: {course.Name}");
}
//Deferred Execution
//var beginnerCourses = dbContext.Courses.Where(c => c.IsBeginnerCourse == true); //Error because IsBeginnerCourse is a property that is functional only in memory
//There are somo options to run the case like before, they will be see later in the course
var beginnerCourses = dbContext.Courses.ToList().Where(c => c.IsBeginnerCourse == true); //This will work but has to load all courses in the memory of the app to use the property of IsBeginnerCourse
//IQueryable ---> IEnumerable
//IQueryable: Allows queries to be extended without being executed.
//One query run in the database, but with the filter of the where
IQueryable <Course> coursesIQ = dbContext.Courses;
var filteredIQ = coursesIQ.Where(c => c.Level == 1);
foreach (var course in filteredIQ)
{
Console.WriteLine(course.Name);
}
//One query with all the courses, and the in memory the filter is applied
IEnumerable <Course> coursesIE = dbContext.Courses;
var filteredIE = coursesIQ.Where(c => c.Level == 1);
foreach (var course in filteredIE)
{
Console.WriteLine(course.Name);
}
}
catch (Exception ex)
{
Console.WriteLine("Error:");
Console.WriteLine(ex.Message);
Console.ReadLine();
}
Console.WriteLine("Proceso terminado.");
Console.ReadLine();
}
