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Best design for a changelog / auditing database table? [closed]
I need to create a database table to store different change log/auditing
(when something was added, deleted, modified, etc). I don't need to store particularly detailed info, so I was thinking something along the lines of:
...
Exact difference between CharSequence and String in java [duplicate]
...tring()
)
I must confess I'm a bit surprised that my compiler javac 1.6.0_33 compiles the + obj using StringBuilder.append(Object) instead of StringBuilder.append(CharSequence). The former probably involves a call to the toString() method of the object, whereas the latter should be possible in a m...
Summarizing multiple columns with dplyr? [duplicate]
...
The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
How do you create a REST client for Java? [closed]
...P2). Works on Android. Unfortunately it does not offer a true reactor-loop based async option (see Ning and HTTP components above). However if you use the newer HTTP2 protocol this is less of a problem (assuming connection count is problem).
Ning Async-http-client - provides NIO support. Previously...
How do you overcome the HTML form nesting limitation?
...ete correspond to different actions on the resource: "Save" -> POST /my_resource (creating a new resource) "Save" -> PUT /my_resource (modifying an existing resource) "Delete" -> DELETE /my_resource (destroy the resource) RESTfully speaking, the problem is that a POST is expected to...
Best Practice: Access form elements by HTML id or name attribute?
...u are working with PHP, it's the name attribute that is your index in the $_POST global.
– seth
Mar 12 '10 at 20:56
2
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GetHashCode Guidelines in C#
...e whole story.
The point being made is that for mutable types, you cannot base the hash code on the mutable data because two equal objects must return the same hash code and the hash code has to be valid for the lifetime of the object. If the hash code changes, you end up with an object that gets l...
What are the pros and cons of performing calculations in sql vs. in your application
...lex work - especially not great for procedural work, but very good for set-based work; lousy error-handling, though)
As always, if you do bring the data back to the app-server, minimising the columns and rows will be to your advantage. Making sure the query is tuned and appropriately indexed will ...
Get/pick an image from Android's built-in Gallery app programmatically
...ing at the response from our own action
private static final int SELECT_PICTURE = 1;
private String selectedImagePath;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
findViewById(R.id.Button0...
Determine if a String is an Integer in Java [duplicate]
...t look at each element at least once. I suppose we could micro-optimize it based on the radix, but for all intents and purposes this is as good as you can expect to get.
public static boolean isInteger(String s) {
return isInteger(s,10);
}
public static boolean isInteger(String s, int radix) {...