12 декабря в Яндексе прошла большая встреча, на которой мы подвели промежуточные итоги СУБД ClickHouse как открытого ПО. За это время сотни компаний начали ей пользоваться.
Специалисты из известных компаний рассказывают о своём опыте использования ClickHouse. Чего удалось достичь и с какими проблемами довелось столкнуться.
Другие видео встречи events.yandex.ru/events/meetings/12-dec-2017/
Ребята! У нас новая лекция Сергея Викторовича Нетёсова, нашего главного вирусолога! Два месяца назад в рамках «Недели Дарвина» он рассказал о происхождении коронавируса, а теперь мы решили сделать более актуальное продолжение. Смотрим и не паникуем! А если вы хотите знать о вирусах больше, то добро пожаловать на курс Сергея Викторовича «Основы вирусологии» на Coursera: www.coursera.org/learn/nsu-virology
Сергей Нетёсов — доктор биологических наук, профессор, член-корреспондент РАН, заведующий Лабораторией биотехнологии и вирусологии Факультета естественных наук Новосибирского государственного университета.
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One of the real powerfull elements of AWK is its own in-built functions and today we will look at using the split function with AWK. The syntax for aplit is litited as the following:
split(string,array,[separator]) In simple term split creates an array from a text string, the elements of the array are delimited by the optional separator. If no separator is supplied a space is assumed. In my example I will work with email addresses to extract the domain name john.doe@example.com fed into split(«john.doe@example.com»,DNS,"@") would give:
DNS[1]=john.doe and
DNS[2]=example.com
Se how we then build this into awk to pass data from text files.
Working with the BASH Shell in Linux and Scripting our command line solutions can save us time, money and energy. We can now have some more great fun and see how much we can use the bash shell for in Linux for our scripting solutions.; creating reports easily from the command line against CSV files. The script should be quite easy to read now as we use a while loop to read in the CSV file. We change the file delimiter to be the comma and then we have the line that we read in broken up into the schema elements we need. A report then is easy with colours and search ability. This is very usable
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Now we really have some fun with our scripts adding in TRAP to help make the scripts more robust. We may need our script to exit correctly each time. We can do this by creating a PID file and checking for its existence. If it does exist then the script did not exit cleanly last time. we also then must make sure we provide a method to delete the file as we exit. Scripts normally do not respond to terminate signals sent from kill, but we too can eable this with traps to make sure we listen to calls from the system, I am sure this will help with your scripts and you will want to implement these ideas in some of your projects.
Have you mastered the basics? Handy with a one-liner? Looking to extend your scripting prowess? Come learn to take simple commands and add logic to them to produce speed and efficiency. Manipulate strings to harvest just the nugget of information youre after without extraneous formatting and labels. Learn why I sed awk.