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Delete duplicate records in SQL Server?
...r the dupes by empId, and delete all but the first one.
delete x from (
select *, rn=row_number() over (partition by EmployeeName order by empId)
from Employee
) x
where rn > 1;
Run it as a select to see what would be deleted:
select *
from (
select *, rn=row_number() over (partition b...
What's the difference(s) between .ToList(), .AsEnumerable(), AsQueryable()?
...y we would typically write something like
var query = context.Observations.Select(o => o.Id)
.AsEnumerable().Select(x => MySuperSmartMethod(x))
ToList – which converts an IEnumerable<T> to a List<T> – is often used for this purpose as well. The advantage of...
Compare two objects' properties to find differences?
...pe t1, Type t2) {
var list1 = t1.GetProperties().OrderBy(x => x.Name).Select(x => x.Name);
var list2 = t2.GetProperties().OrderBy(x => x.Name).Select(x => x.Name);
return list1.SequenceEqual(list2);
}
shar...
Get size of all tables in database
...
SELECT
t.NAME AS TableName,
s.Name AS SchemaName,
p.rows,
SUM(a.total_pages) * 8 AS TotalSpaceKB,
CAST(ROUND(((SUM(a.total_pages) * 8) / 1024.00), 2) AS NUMERIC(36, 2)) AS TotalSpaceMB,
SUM(a.used_pa...
How to select rows that have current day's timestamp?
I am trying to select only today's records from a database table.
9 Answers
9
...
Overloaded method selection based on the parameter's real type
...
I expect the method selection to take
in consideration the real (not the
declared) parameter type. Am I missing
something?
Yes. Your expectation is wrong. In Java, dynamic method dispatch happens only for the object the method is called ...
Why does an NSInteger variable have to be cast to long when used as a format argument?
...
I suppose the selected answer is technically the best answer to the question, but if you want to know how to avoid casting each occurrence and prevent warnings then I find this is the best solution.
– Daniel Wood
...
Is there a difference between copy initialization and direct initialization?
...ain function :
int main()
{
A a1 = 1; // OK: copy-initialization selects A::A(int)
A a2(2); // OK: direct-initialization selects A::A(int)
A a3 {4, 5}; // OK: direct-list-initialization selects A::A(int, int)
A a4 = {4, 5}; // OK: copy-list-initialization selects A::A(i...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...CIT) and (utf8_unicode_ci,IMPLICIT) for operation '='
$this->db->select("users.username as matric_no, CONCAT(users.surname,
' ',
users.first_name, ' ', users.last_name) as fullname")
->join('users', 'users.username=classroom_students.matric_no', 'left')
...
SQL query to get all values a enum can have
...
If you want an array:
SELECT enum_range(NULL::myenum)
If you want a separate record for each item in the enum:
SELECT unnest(enum_range(NULL::myenum))
Additional Information
This solution works as expected even if your enum is not in the...