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How to change column datatype in SQL database without losing data
...ing the conversion goes wrong, you can always go back since you still have all the data..
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Returning 'IList' vs 'ICollection' vs 'Collection'
...
Generally you should return a type that is as general as possible, i.e. one that knows just enough of the returned data that the consumer needs to use. That way you have greater freedom to change the implementation of the API, wit...
MySQL: Fastest way to count number of rows
...olumn indexes, so it will be the best result. Mysql with MyISAM engine actually stores row count, it doensn't count all rows each time you try to count all rows. (based on primary key's column)
Using PHP to count rows is not very smart, because you have to send data from mysql to php. Why do it whe...
A clean, lightweight alternative to Python's twisted? [closed]
...her Stackless Python microthreads or Greenlets for light-weight threading. All blocking network I/O is transparently made asynchronous through a single libevent loop, so it should be nearly as efficient as an real asynchronous server.
I suppose it's similar to Eventlet in this way.
The downside is...
GOTO still considered harmful? [closed]
...are generalizations; while it is always possible to plead exception, it usually (in my experience and humble opinion) isn't worth the risks.
Unconstrained use of memory addresses (either GOTO or raw pointers) provides too many opportunities to make easily avoidable mistakes.
The more ways there ar...
Are C++ enums signed or unsigned?
...integral type is used as the underlying type for an enum, except that it shall not be larger than int, unless some value cannot fit into int or an unsigned int.
In short: you cannot rely on an enum being either signed or unsigned.
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What is the difference between `git fetch origin` and `git remote update origin`?
...ports grouped remotes (remotes.<group> = <list>), and updating all remotes (except those with remote.<name>.skipDefaultUpdate set), but not any of the more specific options of fetch. Under the hood, though, it does the exact same thing as fetch with the default options.
The answe...
Invoke a callback at the end of a transition
...// d3 v5
d3.select("#myid").transition().style("opacity","0").on("end", myCallback);
// old way
d3.select("#myid").transition().style("opacity","0").each("end", myCallback);
This demo uses the "end" event to chain many transitions in order.
The donut example that ships with D3 also uses this to ...
How to make all Objects in AWS S3 bucket public by default?
...23327",
"Action": [
"s3:GetObject"
],
"Effect": "Allow",
"Resource": "arn:aws:s3:::bucketnm/*",
"Principal": {
"AWS": [
"*"
]
}
}
]
}
Now go to your AWS S3 console, At the bucket level, click on Properties, Expand Permissi...
Deleting queues in RabbitMQ
...rgin state.
Removes the node from any cluster it belongs to, removes all data from
the management database, such as configured users and vhosts, and
deletes all persistent messages.
So, be careful using it.
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