我在/etc/udev/rules.d/local.rules制作了一个剧本
SUBSYSTEM=="usb", SYSFS{idVendor=="b58e"}, SYSFS{idProduct=="9e84"}, ACTION=="add", RUN+="notify-send USB"
然后我重新加载udev
sudo udevadm control --reload-rules
我试图删除除子系统之外的所有内容并运行.我试过运行'='而不是'+ =',我已经厌倦了ATTR而不是SYSFS.我试过"sudo service udev restart"和"sudo reload udev".我拔下设备,然后重新插入它,它不会运行该操作.我尝试将其重命名为70-local.rules并将权限更改为+ x.我已经尝试将'子系统'改为'总线'.我已经尝试将run设置为"/path/test.sh",它具有相同的命令.
假设我有一个看起来像这样的数据集
{"id":15,"classification":"goth","categories":["blackLipstick","hotTopic"]}
{"id":14,"classification":"goth","categories":["drinking","girls","hotTopic"]}
{"id":13,"classification":"jock","categories":["basketball","chicharones","fooball","girls","pop","pregnant","sports","starTrek","tortilla","tostada"]}
{"id":12,"classification":"geek","categories":["academics","cacahuates","computers","glasses","papas","physics","programming","ps4","science"]}
{"id":11,"classification":"geek","categories":["cacahuates","fajitas","math","pregnant","raves","xbox"]}
{"id":10,"classification":"goth","categories":["cutting"]}
{"id":9,"classification":"geek","categories":["cafe","chalupa","chimichangas","manson","physics","pollo","tostada"]}
{"id":8,"classification":"jock","categories":["basketball","chalupa","enchurrito","piercings","running","sports"]}
{"id":7,"classification":"geek","categories":["aguacate","blackLipstick","computers","fajitas","fooball","glasses","lifting","outdoors","physics","pollo","pregnant","ps4"]}
{"id":6,"classification":"none","categories":["brocode","girls","raves","tacos"]}
{"id":5,"classification":"goth","categories":["blackLipstick","blackShirts","drugs","mole","piercings","tattoos","tortilla"]}
{"id":4,"classification":"jock","categories":["girls","tattoos"]}
{"id":3,"classification":"goth","categories":["girls"]}
{"id":2,"classification":"none","categories":["cutting","enchurrito","fooball","pastel","pregnant","tattoos","vampires"]}
{"id":1,"classification":"goth","categories":["cacahuates","cutting","drugs","empanadas","frijoles","manson","nachos","outdoors","piercings","tattoos"]}
{"id":0,"classification":"geek","categories":["pollo","pop","programming","science"]}
我如何写一个查询,我可以说"如果有人有类别'数学'他们经常有什么其他类别？"
对于这个数据集,我可以写这样的东西来告诉我哥们,极客和运动员最喜欢什么.
SELECT classification, categories, count(categories) C
FROM [xx.stereotypes] group by classification
, categories ORDER BY C DESC LIMIT 1000
但在我的真实数据集中,我没有分类字段.我想要一个可以帮助我创建分类的查询,例如"goth","jock"或"geek".
例如,如何选择类别包含"数学"的类别的所有计数,这仅选择数学
SELECT categories, count(categories) C FROM [xx.stereotypes]
where categories CONTAINS "math" group by categories ORDER
BY C DESC LIMIT 1000
我尝试了几件事，但无法读取任何内容
{ok, Port} = gen_udp:open(0, [{ifaddr,{local,"/tmp/socket2"}}]).
然后我切换到控制台。
echo "hi" | socat - UNIX-CONNECT:/tmp/socket2
回到埃尔朗
41> gen_udp:recv(Port, 2, 5000).
{error,timeout}
任何帮助表示赞赏。我也尝试过{active，true} opt和flush（）。什么也没显示。
如何最好地限制对Redshift中某些表的列级访问？
我希望能够授予对表而不是某些列的读访问权限。如果redshift无法做到，那么是否有任何程序可以在redshift之上成为安全层？
目前我几乎可以通过简单地运行从 psql 获取 CSV
psql -A -t -F'\t' -c "SELECT ...;" > myfile.csv
但是它返回文件末尾的行数。我可以修复他的head -n -1
psql -A -t -F'\t' | head -n -1 | -c "SELECT ...;"
但对于非常大的文件似乎有点矫枉过正。psql 中有一个标志可以关闭返回的记录数吗？
如果帖子数据包含"&"字符,则认为它正在分离查询字符串参数.如果它包含+它认为它是一个空间.我确信有一些预先构建的功能可以处理这些事情.
标签是项目级别的，具有字符限制，例如不能有空格。我可以通过bigquery表或在每台服务器上添加元数据。我还可以在默认的appspot存储桶上创建README.txt。
在项目级别添加元数据的最佳方法是什么？诸如项目内容，原因，负责人，利益相关者，开发人员，上下文/词汇之类的事情。例如，当我被解雇时，人们可以看到什么。
我在python 2.7中使用了与concurrent.futures库的Queue.当我在下面运行此代码片段时,它打印四个1并不罕见.我希望线程队列是一种共享数据的方式,但它似乎不是线程安全的.如何使其线程安全？
q = Queue.Queue()
def test():
x = q.get(True)
print x
def thread_pool():
for x in [1,2,3,4,5]:
q.put(x)
#with concurrent.futures.ProcessPoolExecutor(max_workers=2) as executor:
executor = concurrent.futures.ProcessPoolExecutor(max_workers=5)
for x in range(5):
executor.submit(test)