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PostgreSQL DISTINCT ON with different ORDER BY
...ll row that contains the most recent purchased product for each address_id and that result sorted by purchased_at then you're trying to solve a greatest N per group problem which can be solved by the following approaches:
The general solution that should work in most DBMSs:
SELECT t1.* FROM purcha...
Difference Between One-to-Many, Many-to-One and Many-to-Many?
... so this is probably a trivial question but I'm having trouble visualizing and understanding the differences and when to use each. I'm also a little unclear as to how concepts like uni-directional and bi-directional mappings affect the one-to-many/many-to-many relationships. I'm using Hibernate righ...
In Angular, I need to search objects in an array
...s lots of objects. Each has an ID (this is stored in a flat file so no DB, and I seem to not be able to user ng-resource )
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Possibility of duplicate Mongo ObjectId's being generated in two different collections?
...collection-independent; it's global. The Java driver, for example, uses a randomly initialized, static AtomicInteger.
So why, in the Mongo docs, do they say that the IDs are "highly likely" to be unique, instead of outright saying that they WILL be unique? Three possibilities can occur where you w...
Put buttons at bottom of screen with LinearLayout?
...ayout_height="match_parent"
Your inside LinearLayout has layout_weight="1" and layout_height="0dp"
Your TextView has layout_weight="0"
You've set the gravity properly on your inner LinearLayout: android:gravity="center|bottom"
Notice that fill_parent does not mean "take up all available space". Ho...
Insert auto increment primary key to existing table
...a into the primary key column automatically (I already have 500 rows in DB and want to give them id but I don't want to do it manually). Any thoughts? Thanks a lot.
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How to select html nodes by ID with jquery when the id contains a dot?
...iguity here
“#id.class” is a valid selector that requires both an id and a separate class to match; it's valid and not always totally redundant.
The correct way to select a literal ‘.’ in CSS is to escape it: “#id\.moreid”. This used to cause trouble in some older browsers (in particu...
Grouped LIMIT in PostgreSQL: show the first N rows for each group?
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For those who works with like millions rows and seeks for really performant way to do this - poshest's answer is the way to go. Just dont forget to spice ti up with proper indexing.
– Diligent Key Presser
Jun 20 '19 at 8:46
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How do I get a YouTube video thumbnail from the YouTube API?
If I have a YouTube video URL, is there any way to use PHP and cURL to get the associated thumbnail from the YouTube API?
3...
javascript: Clear all timeouts?
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It need not start at 1. The HTML5 spec says "Let handle be a user-agent-defined integer that is greater than zero that will identify the timeout to be set by this call." which leaves room for the handle to be any positive integer including non-consecutive and non-small integ...