public void Select()
{
using (var context = DbContextFactory.GetDbContext())
{
//single
var student = context.From <Student>()
.Where(a => a.Id == 19)
.Single();
//subquery
var id = 0;
var age = 50;
var subquery = new SubQuery <School>()
.Where(a => a.Id >= id)
.Select(a => a.Id);
//Verify that subquery parameters are written to the current query
var students2 = context.From <Student>()
.OrderBy(a => a.Age)
.Where(a => a.Id >= Operator.Any(subquery) && a.Age > age)
.Select();
//Partial columns
var students3 = context.From <Student>()
.Select(s => new
{
s.Id,
s.Age
});
}
}
public void Demo4_Subquery()
{
using (var context = DbContextFactory.GetDbContext())
{
//in where
var subquery1 = new SubQuery <Student>()
.Where(a => a.Id <= 15)
.Select(s => s.Age);
var student1 = context.From <Student>()
.Where(a => a.Age >= Operator.Any(subquery1))
.Select();
//in columns
var subquery2 = new SubQuery <School>()
.Where <Student, School>((a, b) => a.SchoolId == b.Id)
.Select(s => s.Name);
var student2 = context.From <Student>()
.Select(s => new
{
s.Id,
StudentName = s.Name,
SchoolName = (string)subquery2 //just for build
});
}
}
public void Select()
{
using (var context = DbContextFactory.GetDbContext())
{
try
{
//single
var c = Grade.A;
var student = context.From <Student>()
.Where(a => !(a.IsDelete == false) && a.Age > 2)
.Select();
//in
var students1 = context.From <Student>()
.Where(a => Operator.In(a.Id, new[] { 1, 2 }))
.Select();
//subquery
var id = 0;
var age = 50;
var subquery = new SubQuery <School>()
.Where(a => a.Id >= id)
.Select(a => a.Id);
//Verify that subquery parameters are written to the current query
var students2 = context.From <Student>()
.OrderBy(a => a.Age)
.Where(a => a.Id >= Operator.Any(subquery) && a.Age > age)
.Select();
////Partial columns
var students3 = context.From <Student>()
.Select(s => new
{
s.Id,
s.Age
});
}
catch (Exception e)
{
throw;
}
}
}
