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E11000 duplicate key error index in mongodb mongoose
...nt with the sparse index to filter these null values from the unique index and avoid the error.
unique indexes
Sparse indexes only contain entries for documents that have the indexed field, even if the index field contains a null value.
In other words, a sparse index is ok with multiple documents...
How do I calculate the date in JavaScript three months prior to today?
...tation needed. But more than half the time, that is 31 days ago, not 30. And if today is the 31st of the month (and it isn't August or Decemeber), that day of the month doesn't exist in the previous month.
Interestingly, Google agrees with JavaScript if you ask it what day is one month before ano...
How do I drop a MongoDB database from the command line?
...--eval "db.dropDatabase()"
More info on scripting the shell from the command line here: https://docs.mongodb.com/manual/tutorial/write-scripts-for-the-mongo-shell/#scripting
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Best way to get identity of inserted row?
...rns the last identity value generated for any table in the current session and the current scope. Generally what you want to use.
IDENT_CURRENT('tableName') returns the last identity value generated for a specific table in any session and any scope. This lets you specify which table you want the v...
Synchronously waiting for an async operation, and why does Wait() freeze the program here
...ing on a thread pool thread, it doesn't try to come back to the UI thread, and everything therefore works.
Alternatively, you could call StartAsTask().ConfigureAwait(false) before awaiting the inner operation to make it come back to the thread pool rather than the UI thread, avoiding the deadlock e...
Creating a blurring overlay view
...this effect. This is a native API that has been fine-tuned for performance and great battery life, plus it's easy to implement.
Swift:
//only apply the blur if the user hasn't disabled transparency effects
if !UIAccessibility.isReduceTransparencyEnabled {
view.backgroundColor = .clear
let...
Easiest way to flip a boolean value?
... it can be helpful to have a TOGGLE(a) macro. This prevents some mistakes and makes it all more readable on narrow screens.
– OJW
Oct 1 '10 at 12:17
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Convert a PHP script into a stand-alone windows executable
... task. For this I have written a small PHP script which I run from the command line using PHP-CLI. Now I want to hand over this script to someone but I do not want to:
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Angular.js programmatically setting a form field to dirty
I am programmatically updating some of the fields on my form with a value and I would like to set the field state to $dirty . Doing something like:
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How do I use disk caching in Picasso?
I am using Picasso to display image in my android app:
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