大约有 41,000 项符合查询结果（耗时：0.0397秒） [XML]
Linq: GroupBy, Sum and Count
...a" is coming from, but the problem in the console app is that you're using SelectMany to look at each item in each group.
I think you just want:
List<ResultLine> result = Lines
.GroupBy(l => l.ProductCode)
.Select(cl => new ResultLine
{
ProductName =...
Import .bak file to a database in SQL server
...t only accept a restore from that point? I find it very odd that I can not select a backup file to restore.
– James
Nov 21 '16 at 18:49
13
...
How do I use itertools.groupby()?
...string)]
will give you a list of 2-tuples where the first element is the char and the 2nd is the number of repetitions.
Edit: Note that this is what separates itertools.groupby from the SQL GROUP BY semantics: itertools doesn't (and in general can't) sort the iterator in advance, so groups with t...
How to check if mysql database exists
...
SELECT SCHEMA_NAME
FROM INFORMATION_SCHEMA.SCHEMATA
WHERE SCHEMA_NAME = 'DBName'
If you just need to know if a db exists so you won't get an error when you try to create it, simply use (From here):
CREATE DATABASE IF NO...
Is it possible to Pivot data using LINQ?
...t = GetCustData();
var query = myList
.GroupBy(c => c.CustId)
.Select(g => new {
CustId = g.Key,
Jan = g.Where(c => c.OrderDate.Month == 1).Sum(c => c.Qty),
Feb = g.Where(c => c.OrderDate.Month == 2).Sum(c => c.Qty),
March = g.Where(c => ...
Where is android studio building my .apk file?
...
Go to AndroidStudio projects File
Select the project name,
Select app
Select build
Select Outputs
Select Apk
You will find APK files of app here, if you have ran the app in AVD or even hardware device
...
What is the best way to filter a Java Collection?
...without writing loops or inner classes:
List<Person> beerDrinkers = select(persons, having(on(Person.class).getAge(),
greaterThan(16)));
Can you imagine something more readable?
Disclaimer: I am a contributor on lambdaj
...
Multiple file upload in php
... what would the expected outcome be? Browser allowing multiple files to be selected?
– Sven
Oct 3 '12 at 17:41
9
...
How to create a self-signed certificate for a domain name for development?
...g the IIS Manager
Launch the IIS Manager
At the server level, under IIS, select Server Certificates
On the right hand side under Actions select Create Self-Signed Certificate
Where it says "Specify a friendly name for the certificate" type in an appropriate name for reference.
Examples: www.dom...
How to remove an iOS app from the App Store
...
What you need to do is this.
Go to “Manage Your Applications” and select the app.
Click “Rights and Pricing” (blue button at the top right.
Below the availability date and price tier section, you should see a grid of checkboxes for the various countries your app is available in. Click t...