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How do I position one image on top of another in HTML?
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When running the code snippet, the one image is not displaying on top of the other one.
– kojow7
Mar 31 '19 at 4:51
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How to apply multiple transforms in CSS?
Using CSS, how can I apply more than one transform ?
7 Answers
7
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How to drop a list of rows from Pandas dataframe?
...e.drop and pass it a Series of index labels:
In [65]: df
Out[65]:
one two
one 1 4
two 2 3
three 3 2
four 4 1
In [66]: df.drop(df.index[[1,3]])
Out[66]:
one two
one 1 4
three 3 2
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SQL join: selecting the last records in a one-to-many relationship
...ve a table of customers and a table of purchases. Each purchase belongs to one customer. I want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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Rails find_or_create_by more than one attribute?
...2: Not all of these were factored out of rails just the attribute specific ones.
https://github.com/rails/rails/blob/4-2-stable/guides/source/active_record_querying.md
Example
GroupMember.find_or_create_by_member_id_and_group_id(4, 7)
became
GroupMember.find_or_create_by(member_id: 4, group...
asynchronous vs non-blocking
...ndustry.
For example in the classic sockets API, a non-blocking socket is one that simply returns immediately with a special "would block" error message, whereas a blocking socket would have blocked. You have to use a separate function such as select or poll to find out when is a good time to retry...
How to generate an entity-relationship (ER) diagram using Oracle SQL Developer
... Data Modeler → Import → Data Dictionary.
Select a DB connection (add one if none).
Click Next.
Check one or more schema names.
Click Next.
Check one or more objects to import.
Click Next.
Click Finish.
The ERD is displayed.
Export the diagram as follows:
Click File → Data Modeler → Pri...
How do I include a pipe | in my linux find -exec command?
This isn't working. Can this be done in find? Or do I need to xargs?
6 Answers
6
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Ordering by specific field value first
...ou never know.
Second, pay attention to how FIELD() works: it returns the one-based index of the value - in the case of FIELD(priority, "core"), it'll return 1 if "core" is the value. If the value of the field is not in the list, it returns zero. This is why DESC is necessary unless you specify a...
Ball to Ball Collision - Detection and Handling
... elastic collision between the balls, you only need to worry about the component of the velocity that is in the direction of the collision. The other component (tangent to the collision) will stay the same for both balls. You can get the collision components by creating a unit vector pointing in the...