大约有 19,300 项符合查询结果（耗时：0.0345秒） [XML]
mysql - how many columns is too many?
...
It's considered too many once it's above the maximum limit supported by the database.
The fact that you don't need every column to be returned by every query is perfectly normal; that's why SELECT statement lets you explicitly name t...
What is the difference between .*? and .* regular expressions?
...
It is the difference between greedy and non-greedy quantifiers.
Consider the input 101000000000100.
Using 1.*1, * is greedy - it will match all the way to the end, and then backtrack until it can match 1, leaving you with 1010000000001.
.*? is non-greedy. * will match nothing, but then will ...
What's the difference between “Write-Host”, “Write-Output”, or “[console]::WriteLine”?
...ost ("count=" + $count)
# or
write-host "count=$count"
BTW - Watch this video of Jeffrey Snover explaining how the pipeline works. Back when I started learning PowerShell I found this to be the most useful explanation of how the pipeline works.
...
What is a NullReferenceException, and how do I fix it?
...or just as normal via a. Note that accessing it via a.Value throws an InvalidOperationException instead of a NullReferenceException if a is null - you should do the check beforehand, i.e. if you have another on-nullable variable int b; then you should do assignments like if (a.HasValue) { b = a.Valu...
Maven: how to override the dependency added by a library
...cify the version in your current pom. The version specified here will override other.
Forcing a version
A version will always be honoured if it is declared in the current POM with a particular version - however, it should be noted that this will also affect other poms downstream if it is itsel...
Understanding the difference between __getattr__ and __getattribute__
...(instance, attribute_name) ?
– Md. Abu Nafee Ibna Zahid
Jun 20 '18 at 8:23
2
@Md.AbuNafeeIbnaZahi...
Setup RSpec to test a gem (not Rails)
...dded s.add_development_dependency "rspec", ">= 2.0.0" to gemspec and did a bundle install .
4 Answers
...
How to get function parameter names/values dynamically?
... vikasde wants the parameter values in an array also. This is already provided in a local variable named arguments.
excerpt from https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions_and_function_scope/arguments:
The arguments object is not an Array. It is similar to an Ar...
Does JavaScript have “Short-circuit” evaluation?
...ew so far:
First let's inspect the behaviour we are all familiar with, inside the if() block, where we use && to check whether the two things are true:
if (true && true) {
console.log('bar');
}
Now, your first instinct is probably to say: 'Ah yes, quite simple, the code execu...
Rich vs Anemic Domain Model [closed]
I am deciding if I should use a Rich Domain Model over an Anemic Domain Model, and looking for good examples of the two.
10...