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JPA EntityManager: Why use persist() over merge()?
EntityManager.merge() can insert new objects and update existing ones.
15 Answers
15
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Proper way to wait for one function to finish before continuing?
...function firstFunction(_callback){
// do some asynchronous work
// and when the asynchronous stuff is complete
_callback();
}
function secondFunction(){
// call first function and pass in a callback function which
// first function runs when it has completed
firstFunctio...
Fast stable sorting algorithm implementation in javascript
...oking to sort an array of about 200-300 objects, sorting on a specific key and a given order (asc/desc). The order of results must be consistent and stable.
...
Using logging in multiple modules
...logging
logger = logging.getLogger(__name__)
near the top of the module, and then in other code in the module do e.g.
logger.debug('My message with %s', 'variable data')
If you need to subdivide logging activity inside a module, use e.g.
loggerA = logging.getLogger(__name__ + '.A')
loggerB = l...
SQLite - UPSERT *not* INSERT or REPLACE
...no-op if the INSERT would violate a uniqueness constraint. UPSERT is not standard SQL. UPSERT in SQLite follows the syntax established by PostgreSQL.
GOOD but tendous: This will update 2 of the columns.
When ID=1 exists, the NAME will be unaffected.
When ID=1 does not exist, the name will be the...
Spring @Autowired usage
What are the pros and cons of using @Autowired in a class that will be wired up by Spring?
9 Answers
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Should try…catch go inside or outside a loop?
...w which way the performance would be affected, I guess were back to try-it-and-test (as always).
– Jeffrey L Whitledge
Sep 27 '08 at 18:35
1
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Parsing Visual Studio Solution files
...Reference, then I do not have access to SolutionFile. However, if I browse and reference the dll located in the folder above, then it does seem to work.
– Inrego
Aug 24 '17 at 18:12
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What's the canonical way to check for type in Python?
... str (exclude subclasses):
if type(o) is str:
The following also works, and can be useful in some cases:
if issubclass(type(o), str):
See Built-in Functions in the Python Library Reference for relevant information.
One more note: in this case, if you're using Python 2, you may actually want t...
CSS Pseudo-classes with inline styles
...g the delimiting braces), whose formal grammar is given below in the terms and conventions of the CSS core grammar:
declaration-list
: S* declaration? [ ';' S* declaration? ]*
;
Neither selectors (including pseudo-elements), nor at-rules, nor any other CSS construct are allowed.
Think of inlin...