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What do column flags mean in MySQL Workbench?
In MySQL Workbench table editor there are 7 column flags available: PK, NN, UQ, BIN, UN, ZF, AI.
3 Answers
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How to avoid mysql 'Deadlock found when trying to get lock; try restarting transaction'
...AL 900 SECOND
ORDER BY id
) u;
Another thing to keep in mind is that mysql documentation suggest that in case of a deadlock the client should retry automatically. you can add this logic to your client code. (Say, 3 retries on this particular error before giving up).
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mysql create user if not exists
I have a query to check mysql users list for create new user.
2 Answers
2
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Unique constraint that allows empty values in MySQL
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Yes, you can do this. See the MySQL reference (version 5.5).
A UNIQUE index creates a constraint such that all values in the index must be distinct. An error occurs if you try to add a new row with a key value that matches an existing row. For all eng...
How do I get the different parts of a Flask request's url?
...ibutes would be the following:
path /page.html
script_root /myapplication
base_url http://www.example.com/myapplication/page.html
url http://www.example.com/myapplication/page.html?x=y
url_root http://www.example.com/myapplication/
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How do I disable “missing docstring” warnings at a file-level in Pylint?
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I think the fix is relative easy without disabling this feature.
def kos_root():
"""Return the pathname of the KOS root directory."""
global _kos_root
if _kos_root: return _kos_root
All you need to do is add the triple double quotes string in every function.
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Fastest way to determine if an integer's square root is an integer
...st way to determine if a long value is a perfect square (i.e. its square root is another integer):
35 Answers
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JRE 1.7 - java version - returns: java/lang/NoClassDefFoundError: java/lang/Object
...-r -v rt.pack rt.jar
To recursively unpack all .pack files, from the JRE root run:
for /r %f in (*.pack) do "%JAVA_HOME%\bin\unpack200.exe" -r -q "%f" "%~pf%~nf.jar"
*nix
To unpack one .pack file (for example rt.pack), run:
/usr/bin/unpack200 -r -v rt.pack rt.jar
To recursively unpack all ....
ros 基本调试 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...的开发中,还是帮助测试ros的关键部分——你都需要了解如何生成重要的调试日志。
对于开发者来说,如果想准确地找出和判断ros的运行状态,调试信息是非常重要的。从操作系统得到默认的调试输出很容易,但是这些输出对...
Cast int to varchar
... @JonathanSayce I'm not overly familiar with the ins & outs of MySQL and it might not use something arbitrary, but I wouldn't rely on the MySQL engine to be that smart (no offense to MySQL). In order to be sure you get the proper length, I would always explicitly provide one.
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