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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 //...
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...
Eclipse: How do i refresh an entire workspace? F5 doesn't do it
...le->Refresh , it doesn't really refresh anything (perhaps the currently selected project). How do I get eclipse to refresh all of the projects?
...
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 I configure a Python interpreter in IntelliJ IDEA with the PyCharm plugin?
... to File > Project Structure.
Under the Project menu for Project SDK, select "New" and
Select "Python SDK", then select "Local".
Provided you have a Python SDK installed, the flow should be natural from there - navigate to the location your Python installation lives.
...
Reliable method to get machine's MAC address in C#
...aces()
where nic.OperationalStatus == OperationalStatus.Up
select nic.GetPhysicalAddress().ToString()
).FirstOrDefault();
Or:
String firstMacAddress = NetworkInterface
.GetAllNetworkInterfaces()
.Where( nic => nic.OperationalStatus == OperationalStatus.Up &&...
How to force LINQ Sum() to return 0 while source collection is empty
...word
&& l.Property.PropertyId == PropertyId)
.Select(l => l.Amount)
.DefaultIfEmpty(0)
.Sum();
This way, your query will only select the Amount field. If the collection is empty, it will return one element with the value of 0 and then the sum will ...
how to schedule a job for sql query to run daily?
...QL Server Agent node and right click the Jobs node in SQL Server Agent and select 'New Job'
In the 'New Job' window enter the name of the job and a description on the 'General' tab.
Select 'Steps' on the left hand side of the window and click 'New' at the bottom.
In the 'Steps' window enter a step n...
Difference between a theta join, equijoin and natural join
...ed SQL query would be like this (you can play with all the examples here)
SELECT *
FROM Product
JOIN Component
ON Product.Pname = Component.Pname
and the result:
| PNAME | PRICE | CNAME | COST |
----------------------------------
| Laptop | 1500 | CPU | 500 |
| Laptop | 1500 | hdd ...
Hidden Features of Xcode
...m working with a large or unfamiliar project.
To show the Favorites Bar, select the following menu option:
View > Layout > Show Favorites Bar
share
edited Apr 4 '11...