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Does SQLAlchemy have an equivalent of Django's get_or_create?
...ote that begin_nested automatically triggers a flush.
Note that if using MySQL, the transaction isolation level must be set to READ COMMITTED rather than REPEATABLE READ for this to work. Django's get_or_create (and here) uses the same stratagem, see also the Django documentation.
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Using column alias in WHERE clause of MySQL query produces an error
...is
executed, the column value may not yet
be determined.
Copied from MySQL documentation
As pointed in the comments, using HAVING instead may do the work. Make sure to give a read at this WHERE vs HAVING though.
share...
How do I create a variable number of variables?
...s sometimes write code like this:
my_calculator.button_0 = tkinter.Button(root, text=0)
my_calculator.button_1 = tkinter.Button(root, text=1)
my_calculator.button_2 = tkinter.Button(root, text=2)
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The coder is then left with a pile of named variables, with a coding effort of O(m * n), where m ...
Difference between float and decimal data type
What difference does it make when I use float and decimal data types in MySQL?.
12 Answers
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常用快速产品原型设计工具推荐 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...了解用例的用户界面；
系统分析员，用来了解用户界面如何影响系统分析；
设计员，用来了解用户界面如何施加影响及它对系统“内部”的要求；
类测试人员，用来制定测试计划活动。
如何高效完成优秀原型设计，工具自...
What are file descriptors, explained in simple terms?
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COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
sleep 14726 root cwd DIR 8,1 4096 1201140 /home/x
sleep 14726 root rtd DIR 8,1 4096 2 /
sleep 14726 root txt REG 8,1 35000 786587 /bin/sleep
sleep 14726 root mem REG 8,1 11864720 118650...
MySQL Great Circle Distance (Haversine formula)
...script that gets Longitude and Latitude values and then inputs them into a MySQL query. I'd like to make it solely MySQL. Here's my current PHP Code:
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File name? Path name? Base name? Naming standard for pieces of a path
...users\OddThinking\Documents\My Source\Widget\foo.src
Vim calls it file root (:help filename-modifiers)
B) C:\users\OddThinking\Documents\My Source\Widget\foo.src
file name or base name
C) C:\users\OddThinking\Documents\My Source\Widget\foo.src (without dot)
file/name extension
D) C...
Which is more efficient: Multiple MySQL tables or one large table?
I store various user details in my MySQL database. Originally it was set up in various tables meaning data is linked with UserIds and outputting via sometimes complicated calls to display and manipulate the data as required. Setting up a new system, it almost makes sense to combine all of these tabl...
MySQL's now() +1 day
I'm using now() in MySQL query.
4 Answers
4
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