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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...entation:
No warning is generated if the variable does not exist. That means
empty() is essentially the concise equivalent to !isset($var) || $var
== false.
This means that you could use only empty() to determine if the variable is set, and in addition it checks the variable against ...
Can you do greater than comparison on a date in a Rails 3 search?
...
is that safe ? i mean if p[:date] came from user input, can it cause an SQL injection ?
– MhdSyrwan
Jul 8 '12 at 14:55
7
...
Generating a unique machine id
...into a workstation which wrote its cpu internal temperature to that table, meaning my unique id changed every few seconds.
– Thomas
Jan 5 '12 at 19:12
...
What is a “slug” in Django?
...he title of an article to generate a URL. I advise to generate the slug by means of a function, given the title (or another piece of data), rather than setting it manually.
An example:
<title> The 46 Year Old Virgin </title>
<content> A silly comedy movie </content>
<slu...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...
It means display width
Whether you use tinyint(1) or tinyint(2), it does not make any difference.
I always use tinyint(1) and int(11), I used several mysql clients (navicat, sequel pro).
It does not mean anything AT ALL! I ra...
Is R's apply family more than syntactic sugar?
...=p,nrow=n)
for(i in 1:n){
for(j in 1:p){
out[i,j] <- (mean(x[y==ylev[i] & z==zlev[j]]))
}
}
rownames(out) <- ylev
colnames(out) <- zlev
return(out)
}
# Used on the generated data
forloop(X,Y,Z)
# The same using tapply
tapply(X,list(Y,Z),mean)
Both giv...
MongoDB Many-to-Many Association
...e the User know about the Role and the Role know about the User. This way means I'll have to set the Role on the User, and the User on the Role. I guess that's fine though.
– Josh Close
Feb 25 '10 at 19:26
...
Overloading and overriding
...override is when you super class method get override accidentaly or if you mean to do it by using the new keyword in both cases, override or overwrite, the behaivor is diferent when you declare Parent p = new Child(); p.Method(); ... maybe I'm wrong and it is just another way to do almost the same t...
C# Entity-Framework: How can I combine a .Find and .Include on a Model Object?
... Find/Load was better for my case (I had 1:1 relation). @Iravanchi: do you mean to say if I had 1:m relation it would have called m times the store?... because would not make so much sense.
– Learner
Mar 31 '14 at 8:46
...
Setting PayPal return URL and making it auto return?
...generated form code:
<input type='hidden' name='rm' value='2'>
rm means return method;
2 means (post)
Than after user purchases and returns to your site url, then that url gets the POST parameters as well
p.s. if using php, try to insert var_dump($_POST); in your return url(script),the...