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How to print to console using swift playground?
I have been following the Apple Guide for their new language swift, but I don't understand why the bar on the right is only showing "Hello, playground" and not "Hello, world". Can someone explain why the println isn't being printed on the right?
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How to order by with union in SQL?
... @marifrahman sorry to dig an old topic, but it may help others. In case you want the ORDER BY to be applied to the first part of the UNION, protect this SELECT with parenthesis.
– Lideln Kyoku
Jan 10 at 22:02
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Is Zookeeper a must for Kafka?
In Kafka, I would like to use only a single broker, single topic and a single partition having one producer and multiple consumers (each consumer getting its own copy of data from the broker). Given this, I do not want the overhead of using Zookeeper; Can I not just use the broker only? Why is a Zoo...
How to debug Lock wait timeout exceeded on MySQL?
In my production error logs I occasionally see:
11 Answers
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How to wait for a keypress in R?
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As someone already wrote in a comment, you don't have to use the cat before readline(). Simply write:
readline(prompt="Press [enter] to continue")
If you don't want to assign it to a variable and don't want a return printed in the console, wrap th...
Create a new database with MySQL Workbench
Being new to MySQL, I have installed the latest version of the MySQL Workbench (5.2.33). I would like to know how you can create a database with this application. In the Overview tab of the SQL editor there are few "MySQL Schema" displayed, are these schemas the existing databases?
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(Built-in) way in JavaScript to check if a string is a valid number
I'm hoping there's something in the same conceptual space as the old VB6 IsNumeric() function?
37 Answers
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Why is volatile needed in C?
Why is volatile needed in C? What is it used for? What will it do?
18 Answers
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A type for Date only in C# - why is there no Date type?
In our C# project we have the need for representing a date without a time. I know of the existence of the DateTime, however, it incorporates a time of day as well. I want to make explicit that certain variables and method-arguments are date-based . Hence I can't use the DateTime.Date property
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Storing time-series data, relational or non?
I am creating a system which polls devices for data on varying metrics such as CPU utilisation, disk utilisation, temperature etc. at (probably) 5 minute intervals using SNMP. The ultimate goal is to provide visualisations to a user of the system in the form of time-series graphs.
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