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Best way to check for “empty or null value”
... '
Demo
Empty string equals any string of spaces when cast to char(n):
SELECT ''::char(5) = ''::char(5) AS eq1
, ''::char(5) = ' '::char(5) AS eq2
, ''::char(5) = ' '::char(5) AS eq3;
Result:
eq1 | eq2 | eq3
----+-----+----
t | t | t
Test for "null or empty string" w...
PostgreSQL: Difference between text and varchar (character varying)
... article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provide the advantage of instant increase of the length c...
“Keep Me Logged In” - the best approach
...lution
A better solution would be
User is logged in and remember me is selected
Generate Token & signature and store in cookie
The tokens are random and are only valid for single autentication
The token are replace on each visit to the site
When a non-logged user visit the site the signa...
How do I get user IP address in django?
How do I get user's IP in django?
11 Answers
11
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Can I change the root EBS device of my amazon EC2 instance?
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I don't have enough rep to add a comment to the selected answer, but I do want to point out that for me, /dev/sda1 did not work (did not attach as root), but using /dev/xvda worked (attached as root). The instance is one of the newer t2.micro ones using HVM.
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Replace a newline in TSQL
...e any of CR, LF or CR+LF. To get them all, you need something like this:
SELECT REPLACE(REPLACE(@str, CHAR(13), ''), CHAR(10), '')
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Pointer to pointer clarification
...an address, it returns the object at that memory address. So when you do *ipp = ip2, what you are doing is *ipp get the object at the address held in ipp which is ip1 and then assign to ip1 the value stored in ip2, which is the address of j.
Simply
& --> Address of
* --> Value at
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How to link godaddy domain with AWS Elastic Beanstalk environment?
...s).
Now you can link you domain with your Elastic Beanstalk site. To do so select/create proper A record type in Route 53 and set Alias for it:
Hope it helps.
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Access denied for user 'test'@'localhost' (using password: YES) except root user
...' IDENTIFIED BY 'password';
This statement creates a new user and grants selected privileges to it.
I.E.:
GRANT INSERT, SELECT, DELETE, UPDATE ON database.* TO 'user'@'localhost' IDENTIFIED BY 'password';
Take a look at the docs to see all privileges detailed
EDIT: you can look for more info w...
Best way to check if a URL is valid
...CII URLs to be valid; internationalized domain names (containing non-ASCII characters) will fail.
Example:
if (filter_var($url, FILTER_VALIDATE_URL) === FALSE) {
die('Not a valid URL');
}
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