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Jenkins Host key verification failed
...tal: The remote end hung up unexpectedly
– A. M. Mérida
Mar 4 '13 at 8:40
6
...
mongodb count num of distinct values per field/key
...
},
{ $unwind: "$keywords" },
{
$group: {
_id: {$toLower: '$keywords'},
count: { $sum: 1 }
}
},
{
$match: {
count: { $gte: 2 }
}
},
{ $sort : { count : -1} },
{ $limit : 100 }
]);
that give result s...
廉价共享存储解决方案2-drbd+cman+gfs2 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...lic/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
a9:8a:3a:3d:64:eb:0b:de:94:a5:92:e4:ba:5d:f3:de root@gfs_1
The key's rand...
What is the difference between a stored procedure and a view?
...nd why to use each.
Say I have two tables:
tbl_user, with columns: user_id, user_name, user_pw
tbl_profile, with columns: profile_id, user_id, profile_description
So, if I find myself querying from those tables A LOT... instead of doing the join in EVERY piece of SQL, I would define a view like...
搭建高可用mongodb集群（二）—— 副本集 - 大数据 & AI - 清泛网 - 专注C/...
...admin数据库
use admin
#定义副本集配置变量，这里的 _id:”repset” 和上面命令参数“ –replSet repset” 要保持一样。
config = { _id:"repset", members:[
{_id:0,host:"192.168.1.136:27017"},
{_id:1,host:"192.168.1.137:27017"},
{_id:2,host:...
Why can't Python parse this JSON data?
...
Your data is not valid JSON format. You have [] when you should have {}:
[] are for JSON arrays, which are called list in Python
{} are for JSON objects, which are called dict in Python
Here's how your JSON file should look:
{
"maps": [...
boost多索引容器multi_index_container实战 - C/C++ - 清泛网 - 专注C/C++及内核技术
...自boost文档
template<typename Tag,typename MultiIndexContainer>
void print_out_by( const MultiIndexContainer& s )
{
/* obtain a reference to the index tagged by Tag */
const typename boost::multi_index::index<MultiIndexContainer,Tag>::type& i = get<Tag>(s);
t...
In Markdown, what is the best way to link to a fragment of a page, i.e. #some_id?
...v> -- this will mess up the layout for many renderers.
(I have changed id= to name= above. See this answer for the tedious explanation.)
share
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fol...
Where can I find my Facebook application id and secret key?
In my Facebook account, where can I find these application IDs, secret key, all?
7 Answers
...
Inner join vs Where
...he same execution plan, look at these two tables:
CREATE TABLE table1 (
id INT,
name VARCHAR(20)
);
CREATE TABLE table2 (
id INT,
name VARCHAR(20)
);
The execution plan for the query using the inner join:
-- with inner join
EXPLAIN PLAN FOR
SELECT * FROM table1 t1
INNER JOIN table2 t2 ...