大约有 47,000 项符合查询结果（耗时：0.0383秒） [XML]
Max return value if empty query
...oeSize = Workers.Where(x => x.CompanyId == 8)
.Select(x => x.ShoeSize)
.DefaultIfEmpty(0)
.Max();
The zero in DefaultIfEmpty is not necessary.
...
Access restriction: The type 'Application' is not API (restriction on required library rt.jar)
...s restrictions.
Go to the properties of your Java project,
i.e. by selecting "Properties" from the context menu of the project in the "Package Explorer".
Go to "Java Build Path", tab "Libraries".
Expand the library entry
select
"Access rules",
"Edit..." and
"Add..." a "Resolution: Ac...
How to load assemblies in PowerShell?
...me;
These should also work:
Add-Type -AssemblyName $TypeName -PassThru | Select-Object -ExpandProperty Assembly | Select-Object -ExpandProperty FullName -Unique
If I want my script to always use a specific version of a .dll but I can't be certain of where it's installed, how do I determine what ...
GroupBy pandas DataFrame and select most common value
.... To clean the data I have to group by data frame by first two columns and select most common value of the third column for each combination.
...
A circular reference was detected while serializing an object of type 'SubSonic.Schema .DatabaseColu
...
I think maybe selecting the ones I want may work I think the circular reference is because in Event I have IQueryable<Category> which in turn will have a IQueryable<Event>
– Jon
Jul 20 '09...
using facebook sdk in Android studio
... what you want).
Open project structure by Ctrl + Shift + Alt + S and then select dependencies tab. Click on + button and select Module Dependency. In the new window pop up select :facebook.
You should be good to go.
Instructions for older Android Studio and older Facebook SDK
This applies to A...
How to output MySQL query results in CSV format?
...ech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-file/
SELECT order_id,product_name,qty
FROM orders
WHERE foo = 'bar'
INTO OUTFILE '/var/lib/mysql-files/orders.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n';
Using this command columns names will not be e...
Script to kill all connections to a database (More than RESTRICTED_USER ROLLBACK)
... Server 2012 and above
USE [master];
DECLARE @kill varchar(8000) = '';
SELECT @kill = @kill + 'kill ' + CONVERT(varchar(5), session_id) + ';'
FROM sys.dm_exec_sessions
WHERE database_id = db_id('MyDB')
EXEC(@kill);
For MS SQL Server 2000, 2005, 2008
USE master;
DECLARE @kill varchar(8000...
MySQL CONCAT returns NULL if any field contain NULL
...
convert the NULL values with empty string by wrapping it in COALESCE
SELECT CONCAT(COALESCE(`affiliate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
...
What is the advantage of using heredoc in PHP? [closed]
...e day I used to use them to construct SQL queries:
$sql = <<<SQL
select *
from $tablename
where id in [$order_ids_list]
and product_name = "widgets"
SQL;
To me this has a lower probability of introducing a syntax error than using quotes:
$sql = "
select *
from $tablename
where ...