大约有 48,000 项符合查询结果（耗时：0.0220秒） [XML]
Algorithm for creating a school timetable
...rties. It was extremely steep, one property easily able to change it by an order of magnitude up or down - and there were hundreds or thousands of properties in one organism. This resulted in absolutely HUGE numbers as the weights, and as a direct result, need to use a bignum library (gmp) to perfor...
MySQL convert date string to Unix timestamp
... After so many trials your solution worked for me: select * from (SELECT order_increment_id, FROM_UNIXTIME(UNIX_TIMESTAMP(STR_TO_DATE(order_date, '%d %M %Y %h:%i:%s %p')),'%Y-%m-%d') as order_date, email_sent FROM `packingslip_header` where email_sent=0) t where order_date >= '2019-11-13' O...
what happens when you type in a URL in browser [closed]
...these are far more complex in actual use, and the tech stack has become an order of magnitude more complicated since this was written. With this in mind, the following timeline is still somewhat valid:
browser checks cache; if requested object is in cache and is fresh, skip to #9
browser asks OS f...
Completely uninstall PostgreSQL 9.0.4 from Mac OSX Lion?
... tanks again @JamesA. do i need to remove anything manually in order to be sure the slate is wiped completely clean? You can check my latest update with the output of "sudo find"
– Ramy
Nov 7 '11 at 15:26
...
Simple way to transpose columns and rows in SQL?
...oPivot+' , name, value, ROW_NUMBER() over (partition by '+@columnToPivot+' order by '+@columnToPivot+') as rowid
from '+@tableToPivot+'
unpivot
(
value for name in ('+@colsUnpivot+')
) unpiv
) src
pivot
(
sum(value...
prevent property from being serialized in web API
...t you want:
First way: Decorate your field with JsonProperty attribute in order to skip the serialization of that field if it is null.
public class Foo
{
public int Id { get; set; }
public string Name { get; set; }
[JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
publi...
Command not found when using sudo
...
Permission denied
In order to run a script the file must have an executable permission bit set.
In order to fully understand Linux file permissions you can study the documentation for the chmod command. chmod, an abbreviation of change mode, is ...
How does StartCoroutine / yield return pattern really work in Unity?
...those functions that you write are being called by the same main thread in order. You can verify this by placing a while(true); in any of your functions or coroutines. It will freeze the whole thing, even the Unity editor. This is evidence that everything runs in one main thread. This link that Kay ...
What is difference between Errors and Exceptions? [duplicate]
...ions. These are those exceptions that might not happen if everything is in order, but they do occur. Examples include ArrayIndexOutOfBoundException, ClassCastException, etc. Many applications will use try-catch or throws clause for RuntimeExceptions & their subclasses but from the language persp...
How to change the default encoding to UTF-8 for Apache?
...m of the file for a number of reasons (overriding pre-existing directives, order, and just to easily see what I did change from stock config).
– MartinodF
Sep 15 '10 at 2:40
6
...