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PersistentObjectException: detached entity passed to persist thrown by JPA and Hibernate
...d tricky, so it's a dirty workaround in your case. You need to remember at least that when you pass an entity object to merge, it stops being attached to the transaction and instead a new, now-attached entity is returned. This means that if anyone has the old entity object still in their possession,...
NOT IN vs NOT EXISTS
...contributed to the 10 mins, but the other option taking 4 secs explains, atleast to me that NOT EXISTS is far better or at least that IN and EXISTS are not exactly the same and always worth a check before going ahead with code.
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IISExpress returns a 503 error from remote machines
...ate 4 on windows 8. This was my first come back to MS VS since studies (at least 8 years) and now I'm sure that linux rules. On django this kind of setup took me 10min of searching documentation.
turn off firewall for testing
netsh advfirewall set allprofiles state off
setup bindings in my ...
How To Create Table with Identity Column
...hat tool probably doesn't have, a "use simpler syntax if possible" option. Least error prone, for OP's specific situation, would be to edit the one line in the generated DDL, and not try to write it from scratch using simplest syntax. Also the example you gave does not assign a name to the PK constr...
How to remove constraints from my MySQL table?
...key constraints, it appears you still need the DROP FOREIGN KEY syntax, at least in MariaDB version 10.2
– Frank Forte
Dec 20 '18 at 18:58
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Replace comma with newline in sed on MacOS?
...'
You need a backslash-escaped literal newline to get to sed.
In bash at least, $'' strings will replace \n with a real newline, but then you have to double the backslash that sed will see to escape the newline, e.g.
echo "a,b" | sed -e $'s/,/\\\n/g'
Note this will not work on all shells, but w...
creating a strikethrough text?
... API or version are useful. If there is any rule in stackoverflow which at least recommed it, I will do it without problems.
– Ignacio Alorre
Aug 25 '17 at 5:53
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Difference between “read commited” and “repeatable read”
... data.
under REPEATABLE READ the second SELECT is guaranteed to display at least the rows that were returned from the first SELECT unchanged. New rows may be added by a concurrent transaction in that one minute, but the existing rows cannot be deleted nor changed.
under SERIALIZABLE reads the second...
How do you create a random string that's suitable for a session ID in PostgreSQL?
...out 1020 bits, just reading the file once from end to end would result, at least, in about 100 times more mis-read UUIDs than duplicates. Storage, network, power, and other hardware and software errors would undoubtedly be thousands of times more frequent than UUID duplication problems.
source: wi...
How to dynamically change header based on AngularJS partial view?
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If you're dead set on using $rootScope I'd at least extract this out to a service so you don't have $rootScope in your controller.
– Michael J. Calkins
Dec 5 '14 at 17:29
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