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Update Row if it Exists Else Insert Logic with Entity Framework
...s.AddObject(myEntity);
}
// Attached object tracks modifications automatically
context.SaveChanges();
If you can use any knowledge about the object's key you can use something like this:
if (myEntity.Id != 0)
{
context.MyEntities.Attach(myEntity);
context.ObjectStateManager.ChangeObject...
ruby inheritance vs mixins
...odules don’t have instances. It follows that entities or things are generally best
modeled in classes, and characteristics or properties of entities or things are
best encapsulated in modules. Correspondingly, as noted in section 4.1.1, class
names tend to be nouns, whereas module names are oft...
Can someone explain mappedBy in JPA and Hibernate?
...that. You're telling both models that they "own" the IDAIRLINE column. Really only one of them actually should! The 'normal' thing is to take the @JoinColumn off of the @OneToMany side entirely, and instead add mappedBy to the @OneToMany.
@OneToMany(cascade = CascadeType.ALL, mappedBy="airline")...
Fluid or fixed grid system, in responsive design, based on Twitter Bootstrap
...idth and fluid width you need to think in terms of your ENTIRE page. Generally, you want to pick one or the other, but not both. The examples you listed in your question are, in-fact, in the same fixed-width page. In other words, the Scaffolding page is using a fixed-width layout. The fixed grid ...
How dangerous is it to access an array out of bounds?
... repeatedly accessing a single memory location in a tight loop could literally cause that chunk of memory to melt. Other possibilities include destroying a CRT display, and moving the read/write head of a disk drive with the harmonic frequency of the drive cabinet, causing it to walk across a table...
Rollback to an old Git commit in a public repo
...hould be good.
You can undo this by
git reset --hard
that will delete all modifications from the working directory and staging area.
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SET versus SELECT when assigning variables?
...ed then SET will assign NULL, where SELECT will not make the assignment at all (so the variable will not be changed from its previous value)
As far as speed differences - there are no direct differences between SET and SELECT. However SELECT's ability to make multiple assignments in one shot does ...
How can I pad a value with leading zeros?
... If performance is a concern for you, don't use this solution!
Potentially outdated: ECMAScript 2017 includes String.prototype.padStart and Number.prototype.toLocaleString is there since ECMAScript 3.1. Example:
var n=-0.1;
n.toLocaleString('en', {minimumIntegerDigits:4,minimumFractionDigits:2...
Check synchronously if file/directory exists in Node.js
... Note that fs.exists() is deprecated, but fs.existsSync() is not. (The
callback parameter to fs.exists() accepts parameters that are
inconsistent with other Node.js callbacks. fs.existsSync() does not
use a callback.)
You've specifically asked for a synchronous check, but if you can use an ...
Elegant way to search for UTF-8 files with BOM?
For debugging purposes, I need to recursively search a directory for all files which start with a UTF-8 byte order mark (BOM). My current solution is a simple shell script:
...