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MongoDB SELECT COUNT GROUP BY
...ate:
db.contest.aggregate([
{"$group" : {_id:"$province", count:{$sum:1}}}
])
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Find the index of a dict within a list, by matching the dict's value
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149
tom_index = next((index for (index, d) in enumerate(lst) if d["name"] == "Tom"), None)
# 1
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How to enable Ad Hoc Distributed Queries
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221
The following command may help you..
EXEC sp_configure 'show advanced options', 1
RECONFIGURE
G...
javascript remove “disabled” attribute from html input
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201
Set the element's disabled property to false:
document.getElementById('my-input-id').disabled =...
How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
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6173
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Replace specific characters within strings
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410
With a regular expression and the function gsub():
group <- c("12357e", "12575e", "197e18",...
搭建高可用mongodb集群（四）—— 分片 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...台机器来做，如下图：
一台机器的一个数据表 Collection1 存储了 1T 数据，压力太大了！在分给4个机器后，每个机器都是256G，则分摊了集中在一台机器的压力。也许有人问一台机器硬盘加大一点不就可以了，为什么要分给四台...
How to put spacing between TBODY elements
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RegEx backreferences in IntelliJ
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196
IntelliJ uses $1 for replacement backreferences.
From IntelliJ's help:
For more informati...