大约有 44,000 项符合查询结果（耗时：0.0708秒） [XML]
How do I alter the position of a column in a PostgreSQL database table?
...e column order is either by
recreating the table, or by adding
columns and rotating data until you
reach the desired layout.
That's pretty weak, but in their defense, in standard SQL, there is no solution for repositioning a column either. Database brands that support changing the ordinal p...
How do I show the changes which have been staged?
...s) against the current HEAD. --staged is a synonym for --cached.
--staged and --cached does not point to HEAD, just difference with respect to HEAD. If you cherry pick what to commit using git add --patch (or git add -p), --staged will return what is staged.
...
Importing Maven project into Eclipse
...ect into eclipse. I found 2 ways to do it, one is through running from command line mvn eclipse:eclipse and another is to install maven eclipse plugin from eclipse. What is the difference between the both and which one is preferable?
The maven-eclipse-plugin is a Maven plugin and has always been t...
How to automatically crop and center an image
... any arbitrary image, I want to crop a square from the center of the image and display it within a given square.
7 Answers
...
What do hjust and vjust do when making a plot using ggplot?
...lot using ggplot, I spend a little while trying different values for hjust and vjust in a line like
2 Answers
...
Release generating .pdb files, why?
...even in the same order as) the generated assembly code. PDB files help you and the debugger out, making post-mortem debugging significantly easier.
You make the point that if your software is ready for release, you should have done all your debugging by then. While that's certainly true, there are ...
Adding a column to a data.frame
...xt, [[.data.frame.
Data frames can be indexed in several modes. When [ and [[ are used with a single vector index (x[i] or x[[i]]), they index the data frame as if it were a list.
my.dataframe["new.col"] <- a.vector
my.dataframe[["new.col"]] <- a.vector
The data.frame method for $, ...
What can I use instead of the arrow operator, `->`?
... them inconsistently. Becomes really annoying when you work with templates and don't know the precise type.
– Konrad Rudolph
Oct 21 '08 at 10:15
1
...
Select N random elements from a List in C#
I need a quick algorithm to select 5 random elements from a generic list. For example, I'd like to get 5 random elements from a List<string> .
...
Use of Finalize/Dispose method in C#
...have to, but you give inheritors of your class a hook to call your Dispose and implement a finalizer themselves if they use unmanaged resources directly:
public class C : B
{
private IntPtr m_Handle;
protected override void Dispose(bool disposing)
{
if (disposing)
{
...