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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
... what situations (if any) it actually is faster!
– svidgen
Jan 9 '13 at 20:56
13
old topic, but f...
How do I associate a Vagrant project directory with an existing VirtualBox VM?
...".vagrant" file in the same directory as your "Vagrantfile" to track the UUID of your VM. This file will not exist if a VM does not exist. The format of the file is JSON. It looks like this if a single VM exists:
{
"active":{
"default":"02f8b71c-75c6-4f33-a161-0f46a0665ab6"
}
}
defaul...
Execute Insert command and return inserted Id in Sql
...table using C# in MVC 4. Actually, I want to insert values and return the 'ID' of last inserted record. I use the following code.
...
Control cannot fall through from one case label
...
switch (searchType)
{
case "SearchBooks":
Selenium.Type("//*[@id='SearchBooks_TextInput']", searchText);
Selenium.Click("//*[@id='SearchBooks_SearchBtn']");
break;
case "SearchAuthors":
Selenium.Type("//*[@id='SearchAuthors_TextInput']", searchText);
...
How to pass parameters to the DbContext.Database.ExecuteSqlCommand method?
Let's just suppose I have a valid need for directly executing a sql command in Entity Framework. I am having trouble figuring out how to use parameters in my sql statement. The following example (not my real example) doesn't work.
...
Restful way for deleting a bunch of items
...:
From:
http://example.com/resources/
do a
POST with a selection of the ID's to:
http://example.com/resources/selections
which, if successful, should respond with:
HTTP/1.1 201 created, and a Location header to:
http://example.com/resources/selections/DF4XY7
On this page you will then see a (j...
Surrogate vs. natural/business keys [closed]
...
If you have multiple "candidate" keys (fields or same-size collections of fields that are NOT NULL UNIQUE) then you are likely in violation of Boyce-Codd Normal Form. BCNF is beyond 3NF, so not many people worry about it. There are situations, howev...
How can I get LINQ to return the object which has the max value for a given property? [duplicate]
...l loop through only once.
Item biggest = items.Aggregate((i1,i2) => i1.ID > i2.ID ? i1 : i2);
Thanks Nick - Here's the proof
class Program
{
static void Main(string[] args)
{
IEnumerable<Item> items1 = new List<Item>()
{
new Item(){ ClientID ...
Can I set enum start value in Java?
...re like classes - and they can even have multiple attributes.
public enum Ids {
OPEN(100), CLOSE(200);
private final int id;
Ids(int id) { this.id = id; }
public int getValue() { return id; }
}
The big difference is that they are type-safe which means you don't have to worry abou...
How to include “zero” / “0” results in COUNT aggregate?
... (and you need to use person as the "driving" table)
SELECT person.person_id, COUNT(appointment.person_id) AS "number_of_appointments"
FROM person
LEFT JOIN appointment ON person.person_id = appointment.person_id
GROUP BY person.person_id;
The reason why this is working, is that the outer (lef...