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The JPA hashCode() / equals() dilemma
... database. However, the problems stem
entirely from allowing objects to exist without an id before they are
saved. We can solve these problems by taking the responsibility of
assigning object IDs away from object-relational mapping frameworks
such as Hibernate. Instead, object IDs can be ass...
Casting vs using the 'as' keyword in the CLR
... of the answers so far (at the time of starting this answer!) have really explained where it's worth using which.
Don't do this:
// Bad code - checks type twice for no reason
if (randomObject is TargetType)
{
TargetType foo = (TargetType) randomObject;
// Do something with foo
}
Not onl...
How can I make git accept a self signed certificate?
...y http.sslCAPath or http.sslCAInfo. Adam Spiers's answer gives some great examples. This is the most secure solution to the question.
To disable TLS/SSL verification for a single git command
try passing -c to git with the proper config variable, or use Flow's answer:
git -c http.sslVerify=false c...
Does C# have extension properties?
Does C# have extension properties?
6 Answers
6
...
How to upgrade PostgreSQL from version 9.6 to version 10.1 without losing data?
... using the PostgreSQL database for my Ruby on Rails application (on Mac OS X 10.9).
15 Answers
...
mongoDB/mongoose: unique if not null
...thout the field by setting the sparse option to true when defining the index. As in:
email : {type: String, trim: true, index: true, unique: true, sparse: true}
Or in the shell:
db.users.ensureIndex({email: 1}, {unique: true, sparse: true});
Note that a unique, sparse index still does not all...
Why is rbindlist “better” than rbind?
... known for being slow when using rbind.data.frame
Where does it really excel
Some questions that show where rbindlist shines are
Fast vectorized merge of list of data.frames by row
Trouble converting long list of data.frames (~1 million) to single data.frame using do.call and ldply
These have...
Execute and get the output of a shell command in node.js
In a node.js, I'd like to find a way to obtain the output of a Unix terminal command. Is there any way to do this?
5 Answer...
Sending POST data in Android
I'm experienced with PHP, JavaScript and a lot of other scripting languages, but I don't have a lot of experience with Java or Android.
...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...nt to be speedy, because they work with large volumes of data or they are executed very frequently. If these queries benefit from eliminating a join, and do not suffer by using a varchar primary key, then do it.
Don't use either strategy for all tables in your database. It's likely that in some c...