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Compare a string using sh shell
...shell and I am trying to compare a string with a variable's value but the if condition is always execute to true. Why?
7 ...
Is it safe to check floating point values for equality to 0?
...equality between double or decimal type values normally, but I'm wondering if 0 is a special case.
9 Answers
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The written versions of the logical operators
.... When I wrote up a test program in NetBeans, I got the red underlining as if there was a syntax error and figured the website was wrong, but it is NetBeans which is wrong because it compiled and ran as expected.
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MySQL load NULL values from CSV data
...field into a local variable, and then sets the actual field value to NULL, if the local variable ends up containing an empty string:
LOAD DATA INFILE '/tmp/testdata.txt'
INTO TABLE moo
FIELDS TERMINATED BY ","
LINES TERMINATED BY "\n"
(one, two, three, @vfour, five)
SET four = NULLIF(@vfour,'')
;
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Release generating .pdb files, why?
... debugging. Optimizations really do a number on your code, making it very difficult to find the culprit if something goes wrong (say, an exception is thrown). Even setting breakpoints is extremely difficult, because lines of source code cannot be matched up one-to-one with (or even in the same order...
Proper way to catch exception from JSON.parse
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i post something into an iframe then read back the contents of the iframe with json parse...so sometimes it's not a json string
Try this:
if(response) {
try {
a = JSON.parse(response);
} catch(e) {
alert(e); // error in the...
How do I convert uint to int in C#?
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Given:
uint n = 3;
int i = checked((int)n); //throws OverflowException if n > Int32.MaxValue
int i = unchecked((int)n); //converts the bits only
//i will be negative if n > Int32.MaxValue
int i = (int)n; //same behavior as unchecked
or
int i = Convert.ToInt3...
Why are global variables evil? [closed]
...so Evil? - Software Engineering Stack Exchange
Are global variables bad?
If you want to go deeper and find out why side effects are all about, and many other enlightening things, you should learn Functional Programming:
Side effect (computer science) - Wikipedia
Why are side-effects considered e...
Database: To delete or not to delete records
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It definitely depends on the actual content of your database. If you're using it to store session information, then by all means wipe it immediately when the session expires (or is closed), you don't want that garbage lying around. As it cannot really be used again for any practical pur...
Traverse all the Nodes of a JSON Object Tree with JavaScript
...a JSON object tree, but cannot find any library for that. It doesn't seem difficult but it feels like reinventing the wheel.
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