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How do shift operators work in Java? [duplicate]
...ts so that the value can be used as an index into the array of hexadecimal characters.
// Masking sign extension.
class HexByte {
static public void main(String args[]) {
char hex[] = {
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};
byte b ...
Select where count of one field is greater than one
...clause, for aggregate result comparison.
Taking the query at face value:
SELECT *
FROM db.table
HAVING COUNT(someField) > 1
Ideally, there should be a GROUP BY defined for proper valuation in the HAVING clause, but MySQL does allow hidden columns from the GROUP BY...
Is this in preparati...
LINQ query to select top five
...
var list = (from t in ctn.Items
where t.DeliverySelection == true && t.Delivery.SentForDelivery == null
orderby t.Delivery.SubmissionDate
select t).Take(5);
share
...
How to select all records from one table that do not exist in another table?
...
SELECT t1.name
FROM table1 t1
LEFT JOIN table2 t2 ON t2.name = t1.name
WHERE t2.name IS NULL
Q: What is happening here?
A: Conceptually, we select all rows from table1 and for each row we attempt to find a row in table2 wi...
jQuery count child elements
...
You can use .length with just a descendant selector, like this:
var count = $("#selected li").length;
If you have to use .children(), then it's like this:
var count = $("#selected ul").children().length;
You can test both versions here.
...
How can I return NULL from a generic method in C#?
...l if T is a reference type (or a nullable value type), 0 for int, '\0' for char, etc. (Default values table (C# Reference))
Restrict T to be a reference type with the where T : class constraint and then return null as normal
...
Add … if string is too long PHP [duplicate]
...lay the whole field, but on the other, I just want to display the first 50 characters. If the string in the description field is less than 50 characters, then it won't show ... , but if it isn't, I will show ... after the first 50 characters.
...
Force CloudFront distribution/file update
...Click on Blank Function (custom)
Step 3
Click on empty (stroked) box and select S3 from combo
Step 4
Select your Bucket (same as for CloudFront distribution)
Step 5
Set an Event Type to "Object Created (All)"
Step 6
Set Prefix and Suffix or leave it empty if you don't know what it is.
Step ...
Why do pthreads’ condition variable functions require a mutex?
...pthread_cond_wait(&cond); //imagine cond_wait did not have a mutex
char *data = some_data;
some_data = NULL;
handle(data);
}
you'd naturally get a lot of race condition, what if the other thread did some_data = new_data right after you got woken up, but before you did data = some_d...
How to check if a database exists in SQL Server?
...script:
DECLARE @dbname nvarchar(128)
SET @dbname = N'Senna'
IF (EXISTS (SELECT name
FROM master.dbo.sysdatabases
WHERE ('[' + name + ']' = @dbname
OR name = @dbname)))
-- code mine :)
PRINT 'db exists'
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