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LEFT OUTER JOIN in LINQ
...c.Category equals p.Category into ps
from p in ps.DefaultIfEmpty()
select new { Category = c, ProductName = p == null ? "(No products)" : p.ProductName };
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How can I select an element by name with jQuery?
...
You can use the jQuery attribute selector:
$('td[name ="tcol1"]') // matches exactly 'tcol1'
$('td[name^="tcol"]' ) // matches those that begin with 'tcol'
$('td[name$="tcol"]' ) // matches those that end with 'tcol'
$('td[name*="tcol"]' ) // matche...
How do I check if an index exists on a table field in MySQL?
...
Try:
SELECT * FROM information_schema.statistics
WHERE table_schema = [DATABASE NAME]
AND table_name = [TABLE NAME] AND column_name = [COLUMN NAME]
It will tell you if there is an index of any kind on a certain column wi...
How do you display code snippets in MS Word preserving format and syntax highlighting?
...d install Notepad++ and do the following:
Paste your code in the window;
Select the programming language from the language menu;
Select the text to copy;
Right click and select Plugin commands -> Copy Text with Syntax Highlighting;
Paste it into MS Word and you are good to go!
Update 29/06/20...
SQL JOIN vs IN performance?
...king, IN and JOIN are different queries that can yield different results.
SELECT a.*
FROM a
JOIN b
ON a.col = b.col
is not the same as
SELECT a.*
FROM a
WHERE col IN
(
SELECT col
FROM b
)
, unless b.col is unique.
However, this is the syno...
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...
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.
...
Join/Where with LINQ and Lambda
...tabase.Post_Metas on post.ID equals meta.Post_ID
where post.ID == id
select new { Post = post, Meta = meta };
If you're really stuck on using lambdas though, your syntax is quite a bit off. Here's the same query, using the LINQ extension methods:
var id = 1;
var query = database.Posts //...
How to select rows from a DataFrame based on column values?
How to select rows from a DataFrame based on values in some column in Pandas?
10 Answers
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Postgresql aggregate array
...
Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the columns on SELECT to GROUP BY,...