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What are the use cases for selecting CHAR over VARCHAR in SQL?
...R(10) = 10 bytes (4 bytes of waste)
The bottom line is CHAR can be faster and more space-efficient for data of relatively the same length (within two characters length difference).
Note: Microsoft SQL has 2 bytes of overhead for a VARCHAR. This may vary from DB to DB, but generally, there is at lea...
What is a magic number, and why is it bad? [closed]
...tion("password");
}
}
}
It improves readability of the code and it's easier to maintain. Imagine the case where I set the size of the password field in the GUI. If I use a magic number, whenever the max size changes, I have to change in two code locations. If I forget one, this will l...
JavaScript checking for null vs. undefined and difference between == and ===
...hey're falsey:
if (!a) {
// `a` is falsey, which includes `undefined` and `null`
// (and `""`, and `0`, and `NaN`, and [of course] `false`)
}
This is defined by ToBoolean in the spec.
...and what is the difference between the null and undefined?
They're both values usually used to i...
“where 1=1” statement [duplicate]
...
It's usually when folks build up SQL statements.
When you add and value = "Toyota" you don't have to worry about whether there is a condition before or just WHERE. The optimiser should ignore it
No magic, just practical
Example Code:
commandText = "select * from car_table where 1=1...
How can I troubleshoot my Perl CGI script?
I have a Perl script that isn't working and I don't know how to start narrowing down the problem. What can I do?
8 Answers
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what is “strict mode” and how is it used?
...en looking over the JavaScript reference on the Mozilla Developer Network, and I came across something called "strict mode" . I read it over and I'm having trouble understanding what it does. Can someone briefly explain (in general) what its purpose is and how it is useful?
...
What is the best way to auto-generate INSERT statements for a SQL Server table?
We are writing a new application, and while testing, we will need a bunch of dummy data. I've added that data by using MS Access to dump excel files into the relevant tables.
...
What is the javascript filename naming convention? [closed]
...e.js
where the product-name + plugin pair can also represent a namespace and a module. The version and filetype are usually optional.
filetype can be something relative to how the content of the file is. Often seen are:
min for minified files
custom for custom built or modified files
Examples...
Which is faster: while(1) or while(2)?
...
jmp .L2
.seh_endproc
.ident "GCC: (tdm64-2) 4.8.1"
With -O2 and -O3 (same output):
.file "main.c"
.intel_syntax noprefix
.def __main; .scl 2; .type 32; .endef
.section .text.startup,"x"
.p2align 4,,15
.globl main
.def main; .scl 2; ....
Difference between return and exit in Bash functions
What is the difference between the return and exit statement in Bash functions with respect to exit codes?
10 Answers
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