大约有 47,000 项符合查询结果（耗时：0.0542秒） [XML]
what is the difference between ?:, ?! and ?= in regex?
I searched for the meaning of these expressions but couldn't understand the exact difference between them.
This is what they say:
...
Ways to save enums in database
...store enumerations as numerical ordinal values anymore; it makes debugging and support way too difficult. We store the actual enumeration value converted to string:
public enum Suit { Spade, Heart, Diamond, Club }
Suit theSuit = Suit.Heart;
szQuery = "INSERT INTO Customers (Name, Suit) " +
...
Tricks to manage the available memory in an R session
...ive R session? I use the functions below [based on postings by Petr Pikal and David Hinds to the r-help list in 2004] to list (and/or sort) the largest objects and to occassionally rm() some of them. But by far the most effective solution was ... to run under 64-bit Linux with ample memory.
...
Internet Explorer 11 detection
...t && !!document.documentMode;
// true on IE11
// false on Edge and other IEs/browsers.
Original Answer
In order to check Ie11 , you can use this : ( tested)
(or run this)
!(window.ActiveXObject) && "ActiveXObject" in window
I have all VMS of IE :
Notice : this w...
Node.js + Nginx - What now?
I've set up Node.js and Nginx on my server. Now I want to use it, but, before I start there are 2 questions:
12 Answers
...
How to import multiple .csv files at once?
...you have those CSVs in a single directory--your current working directory--and that all of them have the lower-case extension .csv.
If you then want to combine those data frames into a single data frame, see the solutions in other answers using things like do.call(rbind,...), dplyr::bind_rows() or ...
What is the purpose of base 64 encoding and why it used in HTTP Basic Authentication?
...pedia page for HTTP Basic Authentication:
While encoding the user name and password with the Base64 algorithm typically makes them unreadable by the naked eye, they are as easily decoded as they are encoded. Security is not the intent of the encoding step. Rather, the intent of the encoding is t...
How to print number with commas as thousands separators?
I am trying to print an integer in Python 2.6.1 with commas as thousands separators. For example, I want to show the number 1234567 as 1,234,567 . How would I go about doing this? I have seen many examples on Google, but I am looking for the simplest practical way.
...
How do you truncate all tables in a database using TSQL?
...
EXEC sp_MSForEachTable 'TRUNCATE TABLE ?'
Couple more links for 2000 and 2005/2008..
share
|
improve this answer
|
follow
|
...
How does the HyperLogLog algorithm work?
I've been learning about different algorithms in my spare time recently, and one that I came across which appears to be very interesting is called the HyperLogLog algorithm - which estimates how many unique items are in a list.
...