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A good book for learning D3.js [closed]
I saw D3.js and I was interested so I bought this book ! I may be wrong, however I found it un-fulfilling.
3 Answers
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How to use redis PUBLISH/SUBSCRIBE with nodejs to notify clients when data values change?
I'm writing an event-driven publish/subscribe application with NodeJS and Redis. I need an example of how to notify web clients when the data values in Redis change.
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Add text to Existing PDF using Python
...ext to an existing PDF using Python, what is the best way to go about this and what extra modules will I need to install.
8...
Is object empty? [duplicate]
...y = Object.prototype.hasOwnProperty;
function isEmpty(obj) {
// null and undefined are "empty"
if (obj == null) return true;
// Assume if it has a length property with a non-zero value
// that that property is correct.
if (obj.length > 0) return false;
if (obj.length...
NSInvocation for Dummies?
...message rendered static, that is, it is an action turned into an object.
And, in a little more detail:
The concept of messages is central to the objective-c philosophy. Any time you call a method, or access a variable of some object, you are sending it a message. NSInvocation comes in handy when ...
ImportError: No module named requests
...requests (or pip3 install requests for python3) if you have pip installed and Pip.exe added to the Path Environment Variable. If pip is installed but not in your path you can use python -m pip install requests (or python3 -m pip install requests for python3)
Alternatively from a cmd prompt, use &g...
Error 1022 - Can't write; duplicate key in table
I'm getting a 1022 error regarding duplicate keys on create table command. Having looked at the query, I can't understand where the duplication is taking place. Can anyone else see it?
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In Firebase, is there a way to get the number of children of a node without loading all the node dat
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The code snippet you gave does indeed load the entire set of data and then counts it client-side, which can be very slow for large amounts of data.
Firebase doesn't currently have a way to count children without loading data, but we do plan to add it.
For now, one solution would be to mai...
“Unable to find manifest signing certificate in the certificate store” - even when add new key
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I've finally found the solution and really hope this helps someone else too.
Edit the .csproj file for the project in question.
Delete the following lines of code:
<PropertyGroup>
<ManifestCertificateThumbprint>...........</ManifestCer...
How to get distinct values for non-key column fields in Laravel?
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I have a table "messages" (used for a chat), and I want to get the latest message that the authenticated user has received from each conversation. Using groupBy I can get just one message, but I get the first, and I need the last message. Seems that orderBy doesn't work...