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Select first row in each GROUP BY group?
As the title suggests, I'd like to select the first row of each set of rows grouped with a GROUP BY .
17 Answers
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Is there a way for non-root processes to bind to “privileged” ports on Linux?
... service as non-root but bind low ports. The short answer is that you do:
setcap 'cap_net_bind_service=+ep' /path/to/program
And then anytime program is executed thereafter it will have the CAP_NET_BIND_SERVICE capability. setcap is in the debian package libcap2-bin.
Now for the caveats:
You w...
Mixing Angular and ASP.NET MVC/Web api?
...together, but in a practical sense, why would you?
An SPA retrieves the assets it needs (JS, CSS, and HTML views) and runs on its own, communicating back to services to send or retrieve data. So, a server-side technology is still necessary for providing those services (as well as other means such a...
Search text in stored procedure in SQL Server
...
Good practice to work with SQL Server.
Create below stored procedure and set short key,
CREATE PROCEDURE [dbo].[Searchinall]
(@strFind AS VARCHAR(MAX))
AS
BEGIN
SET NOCOUNT ON;
--TO FIND STRING IN ALL PROCEDURES
BEGIN
SELECT OBJECT_NAME(OBJECT_ID) SP_Name
...
Convert pandas dataframe to NumPy array
...s been introduced to extract the underlying NumPy array from DataFrames.
# Setup.
df = pd.DataFrame({'A': [1, 2, 3], 'B': [4, 5, 6]}, index=['a', 'b', 'c'])
df.to_numpy()
array([[1, 4],
[2, 5],
[3, 6]])
As mentioned above, this method is also defined on Index and Series objects (see ...
Undefined symbols for architecture armv7
...th you can include the path in the Library Search Paths value in the Build Settings and add -l{library_name_without_lib_and_suffix} (eg. for libz.a use -lz) to the Other Linker Flags section of Build Settings.
You copy files into your project but forgot to check the target to add the files to. To r...
How to search a specific value in all tables (PostgreSQL)?
... recent versions of postgres), you may need to ALTER DATABASE your_db_name SET bytea_output = 'escape'; on the database (or a copy thereof) before dumping it. (I'm not seeing a way to specify this just for a pg_dump command.)
– phils
Aug 10 '15 at 3:01
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Why is TypedReference behind the scenes? It's so fast and safe… almost magical!
...s not included in the CLI Kernel profile:
4.1.6 Vararg
The vararg feature set supports variable-length argument lists and runtime-typed pointers.
If omitted: Any attempt to reference a method with the vararg calling convention or the signature encodings associated with vararg methods (see Partition...
Abusing the algebra of algebraic data types - why does this work?
...hence the exponentiation.
While it's tempting at first to treat types as sets, that doesn't actually work very well in this context--we have disjoint union rather than the standard union of sets, there's no obvious interpretation of intersection or many other set operations, and we don't usually c...
How is this fibonacci-function memoized?
...e from the top, causing the exponential explosion. But with that trick, we set out a list for the interim results, and go "through the list":
fib n = (xs!!(n-1)) + (xs!!(n-2)) where xs = 0:1:map fib [2..]
The trick is to cause that list to get created, and cause that list not to go away (by way o...