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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...
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.
...
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 ...
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...
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...
How to update two tables in one statement in SQL Server 2005?
...wo UPDATE statements are treated atomically. You can also batch them to avoid a round trip.
BEGIN TRANSACTION;
UPDATE Table1
SET Table1.LastName = 'DR. XXXXXX'
FROM Table1 T1, Table2 T2
WHERE T1.id = T2.id
and T1.id = '011008';
UPDATE Table2
SET Table2.WAprrs = 'start,stop'
FROM Table1 T1, Tab...