大约有 48,000 项符合查询结果(耗时:0.0494秒) [XML]
How to COUNT rows within EntityFramework without loading contents?
... where o.ID == '1'
from t in o.MyTable
select t).Count();
Method syntax:
var count = context.MyContainer
.Where(o => o.ID == '1')
.SelectMany(o => o.MyTable)
.Count()
Both generate the same SQL query.
...
Could not find an implementation of the query pattern
...ed to do it using:
var query = (from p in tblPersoon.Cast<Person>() select p).Single();
This kind of error (Could not find an implementation of the query pattern) usually occurs when:
You are missing LINQ namespace usage (using System.Linq)
Type you are querying does not implement IEnumer...
How to make a select with array contains value clause in psql
...
Try
SELECT * FROM table WHERE arr @> ARRAY['s']::varchar[]
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How to truncate string using SQL server
...ou only want to return a few characters of your long string, you can use:
select
left(col, 15) + '...' col
from yourtable
See SQL Fiddle with Demo.
This will return the first 15 characters of the string and then concatenates the ... to the end of it.
If you want to to make sure than strings ...
unable to copy/paste in mingw shell
...
Right-click on the title bar of the command window and select 'Properties', then on the 'Options' tab tick the box for the 'QuickEdit mode', then click 'Ok'.
After that you can paste text from the clipboard using the right mouse-button, highlight text while holding down the left...
Random record from MongoDB
...llection.
db.mycoll.aggregate([{ $sample: { size: 1 } }])
If you want to select the random document(s) from a filtered subset of the collection, prepend a $match stage to the pipeline:
// Get one random document matching {a: 10} from the mycoll collection.
db.mycoll.aggregate([
{ $match: { a:...
Debugging App When Launched by Push Notification
...opdown. (⌘+<)
Than choose your product - 'Run
MyApp.app' on the left.
Select 'Info' tab on the right.
And finally choose "Wait for
MyApp.app to launch" option.
More here in "Customize Executables in the Scheme Editor" section.
EDIT:
In case you miss logs in GDB, see Louis Gerbarg's comment t...
SQL Server Profiler - How to filter trace to only display events from one database?
...
Under Trace properties > Events Selection tab > select show all columns. Now under column filters, you should see the database name. Enter the database name for the Like section and you should see traces only for that database.
...
The entity cannot be constructed in a LINQ to Entities query
... p in db.Products
where p.CategoryID == categoryID
select new ProductDTO { Name = p.Name }).ToList();
}
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Seeking useful Eclipse Java code templates [closed]
...
Format a string
MessageFormat - surround the selection with a MessageFormat.
${:import(java.text.MessageFormat)}
MessageFormat.format(${word_selection}, ${cursor})
This lets me move a cursor to a string, expand the selection to the entire string (Shift-Alt-Up), th...
