大约有 42,000 项符合查询结果（耗时：0.0279秒） [XML]
What does “export” do in shell programming? [duplicate]
... are copied - but for any kind of subprocess, not only for subshells. So a mysql process get value from MYSQL_PWD env var, but would have no concept of MYSQL_PWD shell var.
– David Tonhofer
Dec 24 '18 at 15:43
...
Union of dict objects in Python [duplicate]
How do you calculate the union of two dict objects in Python, where a (key, value) pair is present in the result iff key is in either dict (unless there are duplicates)?
...
Does Python have an ordered set?
...list.
OrderedSet([1, 2, 3])
This is a MutableSet, so the signature for .union doesn't match that of set, but since it includes __or__ something similar can easily be added:
@staticmethod
def union(*sets):
union = OrderedSet()
union.union(*sets)
return union
def union(self, *sets):
...
Set operations (union, intersection) on Swift array?
...ing> = Set(array2)
Swift 3.0+ can do operations on sets as:
firstSet.union(secondSet)// Union of two sets
firstSet.intersection(secondSet)// Intersection of two sets
firstSet.symmetricDifference(secondSet)// exclusiveOr
Swift 2.0 can calculate on array arguments:
set1.union(array2) //...
Turning a Comma Separated string into individual rows
... STUFF(String, 1, CHARINDEX(',', String + ','), '')
FROM Testdata
UNION all
SELECT
SomeID,
OtherID,
LEFT(String, CHARINDEX(',', String + ',') - 1),
STUFF(String, 1, CHARINDEX(',', String + ','), '')
FROM tmp
WHERE
String > ''
)
SELECT...
1030 Got error 28 from storage engine
...
Mysql error "28 from storage engine" - means "not enough disk space".
To show disc space use command below.
myServer# df -h
Results must be like this.
Filesystem Size Used Avail Capacity Mounted on
/dev/vdisk ...
How to see full query from SHOW PROCESSLIST
...ctively running queries & the capacity to end a query on Amazon Aurora MySQL: select id pid, user, concat('CALL mysql.rds_kill(', id, ');'), time, state, info from information_schema.processlist where info is not null order by time desc;
– spen.smith
Sep 9 ...
Efficiently convert rows to columns in sql server
...<| SQL_Code |>] = '' '' '
+ 'UNION ALL '
+ 'SELECT ''----------------------------------------------------------------------------------------------------'' '
+ 'UNION ALL '
...
How to run Django's test database only in memory?
...s line: 'ENGINE': 'sqlite3' if 'test' in sys.argv else 'django.db.backends.mysql',
– mjallday
Jan 19 '11 at 6:26
3
...
使用 C++ 处理 JSON 数据交换格式 - C/C++ - 清泛网 - 专注C/C++及内核技术
...输格式。
本文并不详细介绍 JSON 本身的细节，旨在讨论如何使用 C++ 语言来处理 JSON。关于 JSON 更具体的信息，可参见 JSON 官网：http://www.json.org。
二、本文选择处理 JSON的 C++ 库
本文选择一个第三方库 jsoncpp 来解析 JSON。...