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Random record in ActiveRecord
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I haven't found an ideal way to do this without at least two queries.
The following uses a randomly generated number (up to the current record count) as an offset.
offset = rand(Model.count)
# Rails 4
rand_record = Model.offset(offset).first
# Rails 3
rand_record = Model....
How to update Identity Column in SQL Server?
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@luv at least you have answered to the question that was asked
– Phill Greggan
Jan 26 '15 at 8:09
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How to round an image with Glide library?
...mentioned in previous answer comment this way doesn't work well either. At least for 'de.hdodenhof:circleimageview:1.2.2' + 'com.github.bumptech.glide:glide:3.5.2'. Checked and double checked. Also the same issue with glide 3.4.+ and circleimageview 1.2.1
– Stan
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What are the advantages of NumPy over regular Python lists?
... Python lists -- a list of lists as you describe, in Python, would take at least 20 MB or so, while a NumPy 3D array with single-precision floats in the cells would fit in 4 MB. Access in reading and writing items is also faster with NumPy.
Maybe you don't care that much for just a million cells, b...
How do I find a “gap” in running counter with SQL?
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id
)
WHERE rownum = 1
ANSI (works everywhere, least efficient):
SELECT MIN(id) + 1
FROM mytable mo
WHERE NOT EXISTS
(
SELECT NULL
FROM mytable mi
WHERE mi.id = mo.id + 1
)
Systems supporting sliding window functions...
org.hibernate.MappingException: Could not determine type for: java.util.List, at table: College, for
...o be consistent within a class hierarchy, you can't mix the strategies, at least not in JPA 1.0. JPA 2.0 makes it possible to mix strategies though, but you'd need extra annotations (and thus more complexity). So the recommendation is to pick one strategy and to stick to it in your application. See ...
Jenkins Host key verification failed
...roblem appears, now jenkins will be able to connect the repo (for me ^^ at least)
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Delete duplicate rows from small table
... both original copy and the duplicates. the question is about retaining at least one row.
– pyBomb
Jun 1 at 19:22
@pyB...
Rails migration for has_and_belongs_to_many join table
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@pingu: except that it doesn't work, at least in Rails 3.2. The generated migration file is blank.
– hoffmanc
Jul 7 '13 at 19:23
7
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How to start two threads at “exactly” the same time
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To start the threads at exactly the same time (at least as good as possible), you can use a CyclicBarrier:
// We want to start just 2 threads at the same time, but let's control that
// timing from the main thread. That's why we have 3 "parties" instead of 2.
final CyclicB...