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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 //...
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.
...
“A lambda expression with a statement body cannot be converted to an expression tree”
...SQL to be executed against the database.
Try this
Arr[] myArray = objects.Select(o => new Obj() {
Var1 = o.someVar,
Var2 = o.var2
}).ToArray();
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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 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...
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
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edited Apr 4 '11...
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...
jQuery: Select data attributes that aren't empty?
I'm trying to select all elements that have a data-go-to attribute that is not empty.
11 Answers
...
How to get last N records with activerecord?
...e-wise - at least not up to Rails 3.1. SomeModel.last(5) will execute the select statement without a limit, returning all records of SomeModel to Ruby as an array, after which Ruby will pick out the last (5) elements. Efficiency-wise, currently, you want to use limit - particularly if you have pote...