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Solving a “communications link failure” with JDBC and MySQL [duplicate]

... TOMCAT6_SECURITY=no use validationQuery property use validationQuery="select now()" to make sure each query has responses AutoReconnect Add this code to your connection string: &autoReconnect=true&failOverReadOnly=false&maxReconnects=10 Although non of these solutions worke...
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Is there a use-case for singletons with database access in PHP?

...all one needs to maintain multiple database connections, multiple database selections, multiple database queries, multiple result sets in a given singleton is just keeping them in variables/arrays in the singleton as long as they are needed. This can be as simple as keeping them in arrays, though yo...
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Convert pandas dataframe to NumPy array

...ution, in this case, to_numpy without explaining how to recover the column selecting functionality of as_matrix! I am sure there are other ways to select columns, but as_matrix was at least one of them! – Jérémie Jul 31 '19 at 23:50 ...
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Django in / not in query

... table1.objects.extra(where=["table1.id NOT IN (SELECT table2.key_to_table1 FROM table2 WHERE table2.id = some_parm)"]) share | improve this answer | ...
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Getting and removing the first character of a string

...cters: x <- 'hello stackoverflow' substring(x, 2, nchar(x)) Idea is select all characters starting from 2 to number of characters in x. This is important when you have unequal number of characters in word or phrase. Selecting the first letter is trivial as previous answers: substring(x,1,1...
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Using NumberPicker Widget with Strings

...wrap true or false, try it you will know the difference pickers.setWrapSelectorWheel(false); //create button to test selected text string btnPicker.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { //get position (int)...
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How do I get the entity that represents the current user in Symfony2?

...regular dql like $em = $this->get('doctrine.orm.entity_manager'); "SELECT u FROM Acme\AuctionBundle\Entity\User u where u.username=".$username; $q=$em->createQuery($query); $user=$q->getResult(); the $user should now hold the user with this username ( you could also use other fields ...
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How can I remove an SSH key?

...gether. Go to System --> Preferences --> Startup Applications, and unselect the "SSH Key Agent (Gnome Keyring SSH Agent)" box -- you'll need to scroll down to find it. You'll still get an ssh-agent, only now it will behave sanely: no keys autoloaded, you run ssh-add to add them, and if you w...
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What effect(s) can the virtual keyword have in Entity Framework 4.1 POCO Code First?

... you don't want to fetch that column, never fetch the whole record - just .Select(a=>new { fields you want }). – Scott Stafford Jun 14 '13 at 13:19  |  ...
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How to flatten tree via LINQ?

...IEnumerable<MyNode> Flatten(IEnumerable<MyNode> e) => e.SelectMany(c => Flatten(c.Elements)).Concat(new[] { e }); You can then filter by group using Where(...). To earn some "points for style", convert Flatten to an extension function in a static class. public static IEnume...