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Change one value based on another value in pandas
...we are adding a new description column as a concatenation of other columns by using the + operation which is overridden for series. Fancy string formatting, f-strings etc won't work here since the + applies to scalars and not 'primitive' values:
df['description'] = 'A ' + df.age.astype(str) + ' yea...
What is “the inverse side of the association” in a bidirectional JPA OneToMany/ManyToOne association
...it where in the order table it can save this data (which happens via mappedBy).
Another common example are trees with nodes which can be both parents and children. In this case, the two fields are used in one class:
public class Node {
// Again, this is managed by Hibernate.
// There is no...
Can you resolve an angularjs promise before you return it?
...tory) {
var service = this;
//Object that may be exposed by a controller if desired update using get and put methods provided
service.stuff={
//all kinds of stuff
};
service.listOfStuff = [
{value:"", text:"Please Select"},
...
Is there a way to loop through a table variable in TSQL without using a cursor?
...able. I don't believe the normal downsides of cursors applies here. If row-by-row processing is truly required (and as you point out he should be certain about that first) then using a cursor is a much better solution than the ones you describe here.
– peterh
J...
MySQL Orderby a number, Nulls last
Currently I am doing a very basic OrderBy in my statement.
12 Answers
12
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Naming of ID columns in database tables
... +1 Columns that are synonymous should have the same name - by using the table name prefix you can have a primary key column called table1ID and a foreign key column in another table called table1ID - and you KNOW that they are the same thing. I was taught this 20 years ago and its a...
How to define object in array in Mongoose schema correctly with 2d geo index
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You can declare trk by the following ways : -
either
trk : [{
lat : String,
lng : String
}]
or
trk : { type : Array , "default" : [] }
In the second case during insertion make the object and push it into the array like
db.u...
Cast an instance of a class to a @protocol in Objective-C
...ing to cast to the specific object. So, I would recommend using the answer by @andy anywhere you are casting to a protocol instead of the above -- id<MyProtocol> p = (id<MyProtocol>)self.myViewController; This answer and @andys are both correct, but his is more correct.
...
Is Redis just a cache?
...mple, a Question is a map with fields {id, title, date_asked, votes, asked_by, status}. Similarly, an Answer is a map with fields {id, question_id, answer_text, answered_by, votes, status}. Similarly, we can model a user object.
Each of these objects can be directly stored in Redis as a Hash. To ge...
How can I get device ID for Admob
...
You can try to find key by "RequestConfiguration.Builder().setTestDeviceIds"
– hidd
Sep 23 at 18:01
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