比較
SQL
★
SELECT *
FROM Employee
★
SELECT e.ID, e.Name
FROM Employee AS e
或いは
SELECT e.ID AS ID, e.Name AS Name
FROM Employee AS e
★
SELECT DISTINCT e.ID
FROM Employee AS e
★
SELECT e.*
FROM Employee AS e
WHERE e.ID = '001'
★
SELECT e.* FROM Employee AS e
WHERE e.ID = '001' AND e.DelFlg = 1
★
SELECT e.*
FROM Employee AS e
WHERE e.Start >= 3 AND e.End <= 9
或いは
SELECT e.*
FROM Employee AS e
WHERE e.Score BETWEEN 3 AND 9
★
SELECT e.*
FROM Employee AS e
ORDER BY e.ID
★
SELECT e.*
FROM Employee AS e
ORDER BY e.ID ASC, e.Date DESC
★
SELECT e.*
FROM Employee AS e
WHERE e.Name LIKE 'M%' OR SUBSTRING(e.Name, 0, 4) = 'Mike'
★
SELECT SUM(e.Salary)
FROM Employee AS e
★
SELECT COUNT(*)
FROM Employee AS e
★
SELECT COUNT(*)
FROM Employee AS e
WHERE e.Department = '101'
★
SELECT AVG(e.Score)
FROM Employee AS e
WHERE e.Department = '101'
★
SELECT e.Department, SUM(e.Salary) AS SalarySum
FROM Employee AS e
GROUP BY e.Department
★
SELECT e.Department, SUM(e.Salary) AS SalarySum
FROM Employee AS e
GROUP BY e.Department
HAVING e.COUNT(*) > 2
★
SELECT *
FROM Employee AS e, EmployeeDetail AS ed
★
SELECT *
FROM Employee AS e
INNER JOIN EmployeeDetail AS ed
ON e.ID = ed.ID
★
LINQ
★
from e in Employees
select e
★
from e in Employees
select new {e.ID, e.Name}
或いは
from e in Employees
select new
{
ID = e.ID,
Name = e.Name
}
★
(from e in Employees
select e.ID).Distinct()
或いは
from e in Employees.Distinct()
select e.ID
★
from e in Employees
where e.ID == "001"
select e
★
from e in Employees
where e.ID == "001" && e.DelFlg
select e
★
from e in Employees
where e.Start >= 3 && e.End <= 9
select e
★
from e in Employees
orderby e.ID
select e
★
from e in Employees
orderby e.Date descending, e.ID
select e
或いは
from e in Employees
orderby e.Date descending,
orderby e.ID ascending -- ASCの方が外側
select e
★
from e in Employees
where e.Name.StartsWith("M") || e.Name.Substring(0, 4) = "Mike"
select e
★
(from e in Employees
where e.Department == "101"
select e).Count()
★
(from e in Employees
where e.Department == "101"
select e.Score).Average()
★
from e in Employees
group e by e.Department into g
select new
{
Department = g.Key,
SalarySum = g.Sum(e => e.Salary)
}
★
from e in Employees
group e by e.Department into g
where g.Count() > 2
select new
{
Department = g.Key,
SalarySum = g.Sum(e => e.Salary)
}
★
from e in Employees
from ed in EmployeesDetail
select new{e, ed}
★
from e in Employees
join ed in EmployeesDetail
on e.ID equals ed.ID
select new{e, ed}
★
Lambda
★
Employees
.Select(e => e)
★
Employees
.Select
(
e => new
{
ID = e.ID,
Name = e.Name
}
)
★
Employees
.Select(e => e.ID)
.Distinct()
★
Employees
.Where(e => e.ID == "001")
★
Employees
.Where(e => (e.ID == "001") && e.DelFlg)
★
Employees
.Where(e => ((Int32)e.Start >= 3) && ((Int32)e.End >= 9))
★
Employees
.OrderBy(e => e.ID)
★
Employees
.OrderByDescending(e => e.Date)
.ThenBy(e => e.ID)
或いは
Employees
.OrderByDescending(e => e.Date)
.OrderBy(e => e.ID)
★
Employees
.Where(e => e.Name.StartsWith("M") || (e.Name.Substring(0, 4) == "Mike"))
★
Employees
.Sum(e => e.Salary)
★
Employees.Count()
★
Employees
.Where(e => e.Department == "101")
.Select(e => e)
.Count()
★
Employees
.Where(e => e.Department == "101")
.Select(e => e.Score)
.Average()
★
Employess
.GroupBy(e => e.Department)
.Select
(
g => new
{
Department = g.Key,
SalarySum = g.Sum(e => (Int32)e.Salary)
}
)
★
Employess
.GroupBy(e => e.Department)
.Where(g => g.Count() > 2)
.Select
(
g => new
{
Department = g.Key,
SalarySum = g.Sum(e => (Int32)e.Salary)
}
)
★
Employees
.SelectMany
(
e => EmployeesDetail,
(e, ed) => new
{
e = e,
ed = ed
}
)
★
Employees
.Join
(
EmployeesDetail,
e => e.ID,
ed => ed.ID,
(e, ed) => new
{
e = e,
ed = ed
}
)
★