大约有 15,220 项符合查询结果（耗时：0.0302秒） [XML]
COUNT DISTINCT with CONDITIONS
... be included in count.
One thing to note here is that this can be done by reading the table once. When it seems that you have to read the same table twice or more, it can actually be done by reading once, in most of the time. As a result, it will finish the task a lot faster with less I/O.
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Why use String.Format? [duplicate]
...
I can see a number of reasons:
Readability
string s = string.Format("Hey, {0} it is the {1}st day of {2}. I feel {3}!", _name, _day, _month, _feeling);
vs:
string s = "Hey," + _name + " it is the " + _day + "st day of " + _month + ". I feel " + feeli...
Should I use char** argv or char* argv[]?
...ead is a pointer to the first element of that array. And herein actually already lies the solution. Instead of drawing an array parameter invalid up-front, a C compiler will transform the type of the respective parameter to be a pointer. Remember this, it's very important. The parameter won't be an ...
Random row from Linq to Sql
...t" with "new" with a probability of 1/n where n is the count.
So when you read the first value, you always make that the "current" value. When you read the second value, you might make that the current value (probability 1/2). When you read the third value, you might make that the current value (pr...
Verify a certificate chain using openssl verify
...the comments, this command implicitly trusts Intermediate.pem. I recommend reading the first part of the post Greg references (the second part is specifically about pyOpenSSL and not relevant to this question).
In case the post goes away I'll quote the important paragraphs:
Unfortunately, an "i...
Don't understand why UnboundLocalError occurs (closure) [duplicate]
...er local to increment(). Trying to execute this line, though, will try to read the value of the local variable counter before it is assigned, resulting in an UnboundLocalError.[2]
If counter is a global variable, the global keyword will help. If increment() is a local function and counter a local...
Managing CSS Explosion
...et Formatting
On all 4 my answer has included the advice to download and read Natalie Downe's PDF CSS Systems. (The PDF includes tons of notes not in the slides, so read the PDF!). Take note of her suggestions for organization.
EDIT (2014/02/05) four years later, I'd say:
Use a CSS pre-processo...
Check if at least two out of three booleans are true
...k if this was a real-world requirement (with real variable names) it would read pretty well. Consider return hasGoodAttendance ? (passedCoursework || passed Exam) : (passedCoursework && passedExam), that looks fine to me.
– Andrzej Doyle
Jun 19 '10 at ...
find -exec with multiple commands
...command produces only one line of output and you want them to be easier to read.
– William Turrell
Apr 19 '18 at 12:07
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Rearrange columns using cut
...y commas. Selected input is written
in the same order that it is read, and is written exactly once.
It reaches field 1 first, so that is printed, followed by field 2.
Use awk instead:
awk '{ print $2 " " $1}' file.txt
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