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LINQ to SQL Left Outer Join
... how this crazy syntax works? I fail to see how any of those keywords magically makes it a left join. What does the "into sr" do? Linq frustrates me sometimes :)
– Joe Phillips
Apr 7 '14 at 21:29
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How to read from a file or STDIN in Bash?
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The following solution reads from a file if the script is called
with a file name as the first parameter $1 otherwise from standard input.
while read line
do
echo "$line"
done < "${1:-/dev/stdin}"
The substitution ${1:-...} takes $1 if defined otherwise
the file name of t...
MySQL复制的概述、安装、故障、技巧、工具 - 数据库(内核) - 清泛网 - 专注...
...MyISAM表类型的话，可按如下方式操作：
shell> mysqldump --all-databases --master-data=1 > data.sql
注：master-data选项缺省会打开lock-all-tables，并写入CHANGE MASTER TO语句。
如果数据库使用的是InnoDB表类型的话，则应该使用single-transcation：
s...
List or IList [closed]
...u are exposing your class through a library that others will use, you generally want to expose it via interfaces rather than concrete implementations. This will help if you decide to change the implementation of your class later to use a different concrete class. In that case the users of your lib...
How to get object size in memory? [duplicate]
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Lists in C# are preallocated to whatever sizes the framework designers decided to go with, and then increased when needed. By default it's probably something like 10 elements. So you won't notice any size difference until you add enough element...
What is difference between CrudRepository and JpaRepository interfaces in Spring Data JPA?
...ch.
Because of the inheritance mentioned above, JpaRepository will have all the functions of CrudRepository and PagingAndSortingRepository. So if you don't need the repository to have the functions provided by JpaRepository and PagingAndSortingRepository , use CrudRepository.
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What's the “average” requests per second for a production web application?
... second vs. requests per second. I think requests/second is in that same ballpark(100 to 200) but with streaming it shoots up to 1140 records / second (doing ndjson). Anyways thought I would share more numbers. (not sure if this will change as that was tested streamed through 2 microservices into...
JUnit test for System.out.println()
... outputs the version string, etc etc)
Edit:
Prior versions of this answer called System.setOut(null) after the tests; This is the cause of NullPointerExceptions commenters refer to.
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Distinct() with lambda?
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IEnumerable<Customer> filteredList = originalList
.GroupBy(customer => customer.CustomerId)
.Select(group => group.First());
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Test whether a glob has any matches in bash
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If find feels like overkill and the number of files likely to match is small, use stat:
if stat -t glob* >/dev/null 2>&1
then
echo found
else
echo not found
fi
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