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What is the meaning of the prefix N in T-SQL statements and when should I use it?
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It's declaring the string as nvarchar data type, rather than varchar
You may have seen Transact-SQL code that passes strings around using
an N prefix. This denotes that the subsequent string is in Unicode
(the N actually stands for Nati...
What does the unary plus operator do?
... answered Oct 11 '10 at 2:07
Charles SalviaCharles Salvia
47.1k1212 gold badges116116 silver badges137137 bronze badges
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Why is a round-trip conversion via a string not safe for a double?
...amp;number, &dTest);
if (dTest == value) {
gc.refRetVal = NumberToString(&number, 'G', DOUBLE_PRECISION, gc.numfmt);
goto lExit;
}
DoubleToNumber(value, 17, &number);
DoubleToNumber is pretty simple -- it just calls _ecvt, which is in the C runtime:
void DoubleToNumber(doubl...
Difference between int32, int, int32_t, int8 and int8_t
...ktop/server machines, it probably won't be.
Oops -- missed the part about char. You'd use int8_t instead of char if (and only if) you want an integer type guaranteed to be exactly 8 bits in size. If you want to store characters, you probably want to use char instead. Its size can vary (in terms of ...
Cookies vs. sessions
...omes invalid. If it was all based on cookies, a user (or hacker) could manipulate their cookie data and then play requests to your site.
Edit: I don't think there is any advantage to using cookies, other than simplicity. Look at it this way... Does the user have any reason to know their ID#? Ty...
Master-master vs master-slave database architecture?
... this is that it is very hard to preserve absolute consistency. See the wikipedia article for more.
Wikipedia seems to have a nice summary of the advantages and disadvantages
Advantages
If one master fails, other masters will continue to update the
database.
Masters can be located ...
403 Forbidden vs 401 Unauthorized HTTP responses
...as. I typically use this status code for resources that are locked down by IP address ranges or files in my webroot that I don't want direct access to (i.e. a script must serve them).
– Kyle
May 9 '13 at 13:20
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How to check whether a file is empty or not?
...irst_char:
... print "file is empty" #first character is the empty string..
... else:
... my_file.seek(0) #first character wasn't empty, return to start of file.
... #use file now
...
file is empty
...
Import PEM into Java Key Store
...eate a new java keystore and import the private key and the certificates:
String keypass = "password"; // this is a new password, you need to come up with to protect your java key store file
String defaultalias = "importkey";
KeyStore ks = KeyStore.getInstance("JKS", "SUN");
// this section does ...
Is there a command to refresh environment variables from the command prompt in Windows?
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And annoyingly, extra instances of cmd.exe don't count. They all have to be killed before the change is reflected in any new cmd.exe's.
– Mike F
Oct 5 '08 at 8:08
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