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How can I define a composite primary key in SQL?
...te primary key. It is defined as follows:
CREATE TABLE voting (
QuestionID NUMERIC,
MemberID NUMERIC,
PRIMARY KEY (QuestionID, MemberID)
);
The pair (QuestionID,MemberID) must then be unique for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHER...
in entity framework code first, how to use KeyAttribute on multiple columns
...
InvalidOperationException: Entity type 'XXX' has composite primary key defined with data annotations. To set composite primary key, use fluent API.
– Luca Ziegler
Nov 17 '19 at 18:07
...
Does making a struct volatile make all its members volatile?
...d ($7.1.5.1/8)
[Note: volatile is a hint to the
implementation to avoid aggressive
optimization involving the object
because the value of the object might
be changed by means undetectable by an
implementation. See 1.9 for detailed
semantics. In general, the semantics
of volatile ar...
In Maven 2, how do I know from which dependency comes a transitive dependency?
...
To add to @David Crow, here's a dependency:tree example from the Maven site:
mvn dependency:tree -Dincludes=velocity:velocity
might output
[INFO] [dependency:tree]
[INFO] org.apache.maven.plugins:maven-dependency-plugin:maven-plugin:2....
Reloading module giving NameError: name 'reload' is not defined
...de at import time that isn't designed to run twice. So it is better to avoid reloading, but frequently very convenient.
– Evan
Jul 10 '17 at 20:03
13
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What is the difference between `-fpic` and `-fPIC` gcc parameters?
...
What's more: I did a little experiment here (on x86_64 platform), -fPIC and -fpic appears to have generated the same code. It seems they generate a different code only on m68k, PowerPC and SPARC.
– Denilson Sá Maia
...
Which MIME type to use for a binary file that's specific to my program?
...headers are recognised by the browser for the purpose of a (fast) possible identifying a handler to use the downloaded file as target, for example, PDF would be downloaded and your Adobe Reader program would be executed with the path of the PDF file as an argument,
If your needs are to write a brow...
Return number of rows affected by UPDATE statements
...ards is excellent for.
EXAMPLE
CREATE TABLE [dbo].[test_table](
[LockId] [int] IDENTITY(1,1) NOT NULL,
[StartTime] [datetime] NULL,
[EndTime] [datetime] NULL,
PRIMARY KEY CLUSTERED
(
[LockId] ASC
) ON [PRIMARY]
) ON [PRIMARY]
INSERT INTO test_table(StartTime, EndTime)
VALUES('200...
npm windows install globally results in npm ERR! extraneous
...he site ' http://tech.pro/tutorial/1190/package-managers-an-introductory-guide-for-the-uninitiated-front-end-developer#front_end_developers '.
You should not have to look there now, but I thought it could be good to share the site.
So far so good, til it comes to the global installing. (Ok, some err...
“Width equals height” constraint in Interface Builder
I can't find a way to create a 'square' constraint, meaning 'width equals height' in Interface Builder. I guess it's possible to add such constraint programmatically. Is there something I can do in IB? Maybe I just don't see it? It seems trivial, yet I can't find it.
...