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Auto increment primary key in SQL Server Management Studio 2012
...h non-zero scale) and ofc, the identity spec should be compatible with the selected data type.
– Pred
Feb 4 '15 at 14:36
...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...-date), sum)
# summarising a specific set of non-grouping variables using select_helpers
# see ?select_helpers for more options
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(starts_with('x')), sum)
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(matches('.*...
Embed git commit hash in a .Net dll
...the steps:
Use a Build Event to call git
Right-click on the project and select Properties
In Build Events, add Pre-Build event containing (notice the quotes):
"C:\Program Files\Git\bin\git.exe" describe --long > "$(ProjectDir)\version.txt"
That will create a version.txt file in your project...
How do I clone a range of array elements to a new array?
...want to do Cloning, not just copying references.
In this case you can use .Select to project array members to their clones.
For example, if your elements implemented IClonable you could do something like this:
var newArray = array.Skip(3).Take(5).Select(eachElement => eachElement.Clone()).ToArra...
What are the Android SDK build-tools, platform-tools and tools? And which version should be used?
... Behavior > System Settings > Android SDK
Choose the SDK Tools tab.
Select Android SDK Build Tools from the list
Check Show Package Details.
The last item will show the most recent version.
Make sure it is installed and then write that number as the buildToolsVersion in build.gradle (M...
Access restriction on class due to restriction on required library rt.jar?
...ings in the project properties.
Remove the JRE System Library
Add it back; Select "Add Library" and select the JRE System Library. The default worked for me.
This works because you have multiple classes in different jar files. Removing and re-adding the JRE lib will make the right classes be first...
Why do we need a fieldset tag?
... without using tables. The fieldset tag can be used to create boxes around selected elements and the legend tag will give a caption to those elements. In this way form elements can be grouped together into identified categories.
Different browsers may display the default fieldset border in differen...
What's the @ in front of a string in C#?
...also allows multi-line contents - which can be very handy for SQL:
string select = @"
SELECT Foo
FROM Bar
WHERE Name='Baz'";
The one bit of escaping which is necessary for verbatim string literals is to get a double quote (") which you do by doubling it:
string verbatim = @"He said, ""Would you ...
How to query as GROUP BY in django?
...nnotate(dcount=Count('designation'))
This results in a query similar to
SELECT designation, COUNT(designation) AS dcount
FROM members GROUP BY designation
and the output would be of the form
[{'designation': 'Salesman', 'dcount': 2},
{'designation': 'Manager', 'dcount': 2}]
...
What is `related_name` used for in Django?
... use for prefetch data for Many to many and many to one relationship data.
select_related is to select data from a single value relationship. Both of these are used to fetch data from their relationships from a model. For example, you build a model and a model that has a relationship with other mode...