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JPA EntityManager: Why use persist() over merge()?
EntityManager.merge() can insert new objects and update existing ones.
15 Answers
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The program can't start because libgcc_s_dw2-1.dll is missing
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[GNU gcc link options]
The latter discussion includes -static-libgcc and -static-libstdc++ linker options.
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Rank items in an array using Python/NumPy, without sorting array twice
I have an array of numbers and I'd like to create another array that represents the rank of each item in the first array. I'm using Python and NumPy.
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Flask vs webapp2 for Google App Engine
I'm starting new Google App Engine application and currently considering two frameworks: Flask and webapp2 . I'm rather satisfied with built-in webapp framework that I've used for my previous App Engine application, so I think webapp2 will be even better and I won't have any problems with it.
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Android destroying activities, killing processes
Hi I'm wondering how Android is managing memory and I can't find precise answer anywhere.
Let's assume I have an application with 5 activities on current activity stack (4 are stopped and 1 is resumed), there is no service connected. I press HOME button so that all of my activities are stopped.
I st...
Throttling method calls to M requests in N seconds
...xed size of M. Each time the method is called, you check the oldest entry, and if it's less than N seconds in the past, you execute and add another entry, otherwise you sleep for the time difference.
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When to use actors instead of messaging solutions such as WebSphere MQ or Tibco Rendezvous?
I've already read the question and answers to What design decisions would favour Scala's Actors instead of JMS? .
3 Answer...
What does the “__block” keyword mean?
...eated in a special way when it is used inside a block. Normally, variables and their contents that are also used in blocks are copied, thus any modification done to these variables don't show outside the block. When they are marked with __block, the modifications done inside the block are also visib...
SQL “between” not inclusive
...:
SELECT *
FROM Cases
WHERE cast(created_at as date) BETWEEN '2013-05-01' AND '2013-05-01'
Another way to fix it is with explicit binary comparisons
SELECT *
FROM Cases
WHERE created_at >= '2013-05-01' AND created_at < '2013-05-02'
Aaron Bertrand has a long blog entry on dates (here), wh...
Difference between timestamps with/without time zone in PostgreSQL
...g to the process of inserting/retrieving values. But readers should understand that both data types, timestamp with time zone and timestamp without time zone, in Postgres do *not actually store time zone information. You can confirm this with a glance at the data type doc page: Both types takes up t...