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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 to get script of SQL Server data? [duplicate]
...us to the MySQL dump from SQL Server. I need to be able to pick the tables and export the schema and the data (or I can export the schema via SQL Server Management Studio and export the data separately somehow).
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Flags to enable thorough and verbose g++ warnings
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I went through and found the minimal set of includes that should get the maximum level of warning. I then removed from that list the set of warnings that I feel do not actually indicate something bad is happening, or else have too many fals...
What's the syntax for mod in java
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Careful with the terms mod and modular because n (mod m) IS ALWAYS >= 0 but not n % m. n % m is in the range > -m and < m. Although Java has a remainder operator for int and long types, it has no modulus function or operator. I.e., -12 % 10 = ...
Difference between Arrays.asList(array) and new ArrayList(Arrays.asList(array))
...First, let's see what this does:
Arrays.asList(ia)
It takes an array ia and creates a wrapper that implements List<Integer>, which makes the original array available as a list. Nothing is copied and all, only a single wrapper object is created. Operations on the list wrapper are propagated ...
When is a function too long? [closed]
...t? I'm asking because I have a function with 60 lines (including comments) and was thinking about breaking it apart.
24 Ans...
Program only crashes as release build — how to debug?
...t a program nonetheless) is crashing, but only when built in release mode, and only when launched from the command line. Through caveman debugging (ie, nasty printf() messages all over the place), I have determined the test method where the code is crashing, though unfortunately the actual crash se...
.keyCode vs. .which
... The answer below was written in 2010. Here many years later, both keyCode and which are deprecated in favor of key (for the logical key) and code (for the physical placement of the key). But note that IE doesn't support code, and its support for key is based on an older version of the spec so isn't...
Git - What is the difference between push.default “matching” and “simple”
...t for a while now, but I have never had to set up a new remote repo myself and I have been curious on doing so. I have been reading tutorials and I am confused on how to get "git push" to work.
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The input is not a valid Base-64 string as it contains a non-base 64 character
I have a REST service that reads a file and sends it to another console application after converting it to Byte array and then to Base64 string. This part works, but when the same stream is received at the application, it gets manipulated and is no longer a valid Base64 string. Some junk characters ...