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Find nearest latitude/longitude with an SQL query
...S(latitude / 57.3), 2)) AS distance
FROM TableName HAVING distance < 25 ORDER BY distance;
where [starlat] and [startlng] is the position where to start measuring the distance.
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How to create a MySQL hierarchical recursive query
...
name,
parent_id
from (select * from products
order by parent_id, id) products_sorted,
(select @pv := '19') initialisation
where find_in_set(parent_id, @pv)
and length(@pv := concat(@pv, ',', id))
Here is a fiddle.
Here, the value specified in @pv := '19...
Understanding recursion [closed]
... right child, before we did that we recursed the left child.
In fact, the order in which we called the children, and added the current node's value didn't matter at all, because addition is commutative.
Now let's look at an operation where order does matter. We'll use a binary tree of nodes, but t...
log4j logging hierarchy order
... Although this answers the question (that's just asking for the "hierarchy order"), I finally downvoted for your poor terminology: going down, "visibility" works, item. Didn't you wish to explain how logger configuration affects the actual logging (passing log events)? Please consider another update...
How to reset sequence in postgres and fill id column with new data?
...
If you don't want to retain the ordering of ids, then you can
ALTER SEQUENCE seq RESTART WITH 1;
UPDATE t SET idcolumn=nextval('seq');
I doubt there's an easy way to do that in the order of your choice without recreating the whole table.
...
Difference between JSONObject and JSONArray
...gt;value pairs, tuples or whatever you want to call them)
like {ID : 1}
Order of elements is not important
a JSONObject of {id: 1, name: 'B'} is equal to {name: 'B', id: 1}.
JSONArray:
Contains only series values
like [1, 'value']
Order of values is important
array of [1,'value'] is ...
Call a Server-side Method on a Resource in a RESTful Way
... (i.e., so that intermediaries don’t have to
know the resource type in order to understand the meaning of the
request).
In the above examples, POST is uniformly designed. It will make the dog "bark". That is not safe (meaning bark has effects on the resources), nor idempotent (each request y...
Quicksort vs heapsort
... Quicksort. Heapsort doesn't need more memory for another array to putting ordered data as is needed by Mergesort. So why do comercial applications stick with Quicksort? What Quicksort has that is so special over others implementations?
I've tested the algorithms myself and I've seen that Quicksort...
What's the difference between IComparable & IEquatable interfaces?
...atable tests whether two objects are equal.
IComparable imposes a total ordering on the objects being compared.
For example, IEquatable would tell you that 5 is not equal to 7. IComparable would tell you that 5 comes before 7.
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What is the difference between CascadeType.REMOVE and orphanRemoval in JPA?
...eType.REMOVE and orphanRemoval=true.
For orphan removal:
If you invoke setOrders(null), the related Order entities will be removed in db automatically.
For remove cascade:
If you invoke setOrders(null), the related Order entities will NOT be removed in db automatically.
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