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PostgreSQL Autoincrement
...other integer data type, such as smallint.
Example :
CREATE SEQUENCE user_id_seq;
CREATE TABLE user (
user_id smallint NOT NULL DEFAULT nextval('user_id_seq')
);
ALTER SEQUENCE user_id_seq OWNED BY user.user_id;
Better to use your own data type, rather than user serial data type.
...
Scatterplot with too many points
...;- data.frame(x = rnorm(5000),y=rnorm(5000))
ggplot(df,aes(x=x,y=y)) + geom_point(alpha = 0.3)
Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hexagonal binning:
ggplot(df,aes(x=x,y=y)) + stat_binhex()
And there is also regula...
SQLite DateTime comparison
...e a few datetime functions. Follow the string representation formats (actually only formats 1-10) understood by those functions (storing the value as a string) and then you can use them, plus lexicographical comparison on the strings will match datetime comparison (as long as you don't try to compa...
Collection was modified; enumeration operation may not execute
...
Is that a complete example? I have a class (_dictionary obj below) that contains a generic Dictionary<string,int> named MarkerFrequencies, but doing this didn't instantly solve the crash: lock (_dictionary.MarkerFrequencies) { foreach (KeyValuePair<string, int...
Inserting data into a temporary table
...
To insert all data from all columns, just use this:
SELECT * INTO #TempTable
FROM OriginalTable
Don't forget to DROP the temporary table after you have finished with it and before you try creating it again:
DROP TABLE #TempTable
...
Can I change multiplier property for NSLayoutConstraint?
...them, since "Activating or deactivating the constraint calls addConstraint(_:) and removeConstraint(_:) on the view that is the closest common ancestor of the items managed by this constraint".
– qix
Jan 4 '17 at 5:26
...
How to get nice formatting in the Rails console
...he y method is a handy way to get some pretty YAML output.
y ProductColor.all
Assuming you are in script/console
As jordanpg commented, this answer is outdated. For Rails 3.2+ you need to execute the following code before you can get the y method to work:
YAML::ENGINE.yamler = 'syck'
From rub...
How to convert a string to number in TypeScript?
..., or simply use the unary + operator:
var x = "32";
var y: number = +x;
All of the mentioned techniques will have correct typing and will correctly parse simple decimal integer strings like "123", but will behave differently for various other, possibly expected, cases (like "123.45") and corner c...
How to safely call an async method in C# without await
...it completes, then you can do this:
public string GetStringData()
{
var _ = MyAsyncMethod();
return "hello world";
}
BTW, this is not a "common problem". It's very rare to want to execute some code and not care whether it completes and not care whether it completes successfully.
Update:
Sin...
How to mock ConfigurationManager.AppSettings with moq
...
}
public class ClassUnderTest
{
private readonly NameValueCollection _settings;
public ClassUnderTest(NameValueCollection settings)
{
_settings = settings;
}
public void MethodUnderTest()
{
// get the User from Settings
string user = _settings["Use...