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Create unique constraint with null columns
...(user_id, menu_id, recipe_id), you cannot base CLUSTER on a partial index, and queries without a matching WHERE condition cannot use the partial index. (It seems unlikely you'd want a FK reference three columns wide - use the PK column instead).
If you need a complete index, you can alternatively d...
How to count TRUE values in a logical vector
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@YossiFarjoun Yes, and it's in my answer. This are examples why it won't work. My sollution is sum(z, na.rm = TRUE)
– Marek
May 21 '19 at 13:36
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ES6 class variable alternatives
...many of us are using the following pattern in frameworks to create classes and class variables, which is comfy:
15 Answers
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Declaring pointers; asterisk on the left or right of the space between the type and name? [duplicate
I've seen mixed versions of this in a lot of code. (This applies to C and C++, by the way.) People seem to declare pointers in one of two ways, and I have no idea which one is correct, of if it even matters.
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Can I change the fill color of an svg path with CSS?
...rnal CSS appears to override the path's fill attribute, at least in WebKit and Gecko-based browsers I tested. Of course, if you write, say, <path style="fill: green"> then that will override external CSS as well.
shar...
SQLAlchemy: print the actual query
...enge here is that SQLAlchemy normally is not tasked with this, as this is handled appropriately by the Python DBAPI, not to mention bypassing bound parameters is probably the most widely exploited security holes in modern web applications. SQLAlchemy has limited ability to do this stringification ...
Best way to store date/time in mongodb
I've seen using strings, integer timestamps and mongo datetime objects.
2 Answers
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Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception?
Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception ?
2 Answers
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Git branch diverged after rebase
...se, you're changing the parent of the oldest local commit on your branch - and thus changing the commit hashes of all of your local commits, since this change bubbles up through the commits transitively.
Since you'd already pushed the branch, you should have merged in the source branch, rather than...
What is mutex and semaphore in Java ? What is the main difference?
What is mutex and semaphore in Java ? What is the main difference ?
11 Answers
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