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How do you use Mongoose without defining a schema?
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@a20: I understand what you say about MySQL :) And I think Jonathan suggestion/as per Mongoose API Docs Note: Do not set to false unless you have good reason. Is absolutely fine with the current context (about only NO-SQL)
– Amol M Kulkarni
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ICollection Vs List in Entity Framework
...llection<T> will make it more obvious that the EF creates a bunch of SQL and only returns a List<T> at the end, rather than doing queries for each level of Linq that you use.
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Choosing Java vs Python on Google App Engine
...'inspired' by the datastore but is designed to work with a variety of both SQL databases and NoSQL datastores.
For Python, there are efforts being made to allow the use of the Python GAE datastore API off of the GAE. One example is the SQLite backend that Google released for use with the SDK, but ...
Should functions return null or an empty object?
...value that is universally defined as "no data". That's like stating that a SQL database should return an error if a where clause produces no results. While an Exception is a valid design choice (though one that would irritate me as a consumer), it's not any "more correct" than returning null. And no...
Servlet for serving static content
...y project. The only method you need is coalesce (which is identical to the SQL function COALESCE). This is the code:
public static <T> T coalesce(T...ts) {
for(T t: ts)
if(t != null)
return t;
return null;
}
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postgresql return 0 if returned value is null
...re NULL values in the query.
For all versions I've tested, postgres and mysql will ignore all NULL values when averaging, and it will return NULL if there is nothing to average over. This generally makes sense, as NULL is to be considered "unknown". If you want to override this you can use coalesc...
Preventing Laravel adding multiple records to a pivot table
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@alexandre Butynsky method works very well but use two sql queries.
One to check if cart contains the item and one to save.
To use only one query use this:
try {
$cart->items()->save($newItem);
}
catch(\Exception $e) {}
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WebSockets vs. Server-Sent events/EventSource
..., or other automated data push mechanisms (e.g. updating a client-side Web SQL Database or IndexedDB object store). If you'll need to send data to a server, XMLHttpRequest is always a friend.
SSEs are sent over traditional HTTP. That means they do not require a special protocol or server implem...
How to select different app.config for several build configurations
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$(ProjectDir)App.Config.Settings.xls
MachineName ConfigFilePath SQLServer
default App.config DEVSQL005
Test App.config TESTSQL005
UAT App.config UATSQL005
Production App.config PRODSQL005
YourLocalMachine ...
Multiple queries executed in java in single statement
... as it currently provides an exception even though it is possible in the MySQL query browser.
6 Answers
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