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SQL Server IN vs. EXISTS Performance
...execution operation, to get their results.
An example:
Query 1 ( plan )
select * from dt where dt.customer in (select c.code from customer c where c.active=0)
Query 2 ( plan )
select * from dt where exists (select 1 from customer c where c.code=dt.customer and c.active=0)
...
Nearest neighbors in high-dimensional data?
...
First, the number of features (columns) in a data set is not a factor in selecting a distance metric for use in kNN. There are quite a few published studies directed to precisely this question, and the usual bases for comparison are:
the underlying statistical
distribution of your data;
the rel...
SQL Server Text type vs. varchar data type [closed]
...ts in your database
If you do not search on the value of the column
If you select this column rarely and do not join on it.
VARCHAR is good:
If you store little strings
If you search on the string value
If you always select it or use it in joins.
By selecting here I mean issuing any queries that ...
How to get last inserted id?
...
INSERT INTO aspnet_GameProfiles(UserId,GameId)
VALUES(@UserId, @GameId);
SELECT SCOPE_IDENTITY()
And then
Int32 newId = (Int32) myCommand.ExecuteScalar();
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error, string or binary data would be truncated when trying to insert
...ay cause it.
In my case i was creating the table with a field like this:
Select '' as Period, * From Transactions Into #NewTable
Therefore the field "Period" had a length of Zero and causing the Insert operations to fail. I changed it to "XXXXXX" that is the length of the incoming data and it n...
IIS Express Immediately shutting-down running site after stopping web application
...debugging is stopped.
Right click your project > click Properties > select the 'Web' tab on the left > uncheck the Enable Edit and Continue checkbox.
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How to move the cursor word by word in the OS X Terminal
...e sequences for you:
Open Terminal preferences (cmd+,);
At Settings tab, select Keyboard and double-click ⌥ ← if it's there, or add it if it's not.
Set the modifier as desired, and type the shortcut key in the box: esc+B, generating the text \033b (you can't type this text manually).
Repeat fo...
Create an array or List of all dates between two dates [duplicate]
...
LINQ:
Enumerable.Range(0, 1 + end.Subtract(start).Days)
.Select(offset => start.AddDays(offset))
.ToArray();
For loop:
var dates = new List<DateTime>();
for (var dt = start; dt <= end; dt = dt.AddDays(1))
{
dates.Add(dt);
}
EDIT:
As for padding value...
Remove Project from Android Studio
...This threw me off on a mac too... first, you can't click on the project to select it or it launches the project... you have to trick it by moving your mouse over to highlight and then to make sure it sticks use the keyboard arrow keys up/down to highlight the one you want. Then fn+delete to remove i...
How to apply bindValue method in LIMIT clause?
...ode
$skip = isset($_GET['skip']) ? (int)trim($_GET['skip']) : 0;
$sql = "SELECT * FROM pictures WHERE album = ? ORDER BY id LIMIT ?, ?";
$stmt = $PDO->prepare($sql);
$stmt->execute([$_GET['albumid'], $skip, $max]);
$pictures = $stmt->fetchAll(PDO::FETCH_ASSOC);
...