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CHECK constraint in MySQL is not working
...ySQL Reference Manual says:
The CHECK clause is parsed but ignored by all storage engines.
Try a trigger...
mysql> delimiter //
mysql> CREATE TRIGGER trig_sd_check BEFORE INSERT ON Customer
-> FOR EACH ROW
-> BEGIN
-> IF NEW.SD<0 THEN
-> SET NEW.SD=0;...
How to force vim to syntax-highlight a file as html?
... :set syntax=<type> where <type> is something like perl, html, php, etc.
There is another mechanism that can be used to control syntax highlighting called filetype, or ft for short. Similar to syntax, you give it a type like this: :set filetype=html. Other filetypes are perl, php, etc.
S...
Hook up Raspberry Pi via Ethernet to laptop without router? [closed]
I'm working on a balloon project with a Raspberry Pi. When we potentially recover the Raspberry Pi, it will most likely be in a rural location and I'd like to turn off the Pi at that point safely.
...
SQL - Update multiple records in one query
...e updated so it's just u need to add the parent id and child ids to update all the rows u need using a small script.
UPDATE [Table]
SET couloumn1= (select couloumn1 FROM Table WHERE IDCouloumn = [PArent ID]),
couloumn2= (select couloumn2 FROM Table WHERE IDCouloumn = [PArent ID]),
co...
PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
How do I modify the owner of all tables in a PostgreSQL database?
20 Answers
20
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GSON throwing “Expected BEGIN_OBJECT but was BEGIN_ARRAY”?
...pe. You can't just try and cast the result like that and expect it to magically work ;)
The User guide for Gson Explains how to deal with this:
https://github.com/google/gson/blob/master/UserGuide.md
This will work:
ChannelSearchEnum[] enums = gson.fromJson(yourJson, ChannelSearchEnum[].class);
...
Grunt watch error - Waiting…Fatal error: watch ENOSPC
...
In my case my problem seems to be to have Dropbox installed which seems to use a lot of watches. So I had to use: fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p as in the accepted answer, but +1 for teach me npm dedupe
...
How can I create a link to a local file on a locally-run web page?
...a>
These will never open the file in your local applications automatically. That's for security reasons which I'll cover in the last section. If it opens, it will only ever open in the browser. If your browser can display the file, it will, otherwise it will probably ask you if you want to down...
深入理解 x86/x64 的中断体系 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
...模式执行。只要构建环境要素正确这样切换执行当然是没问题的。
这个执行环境要素需要注意的是：当使用 16-bit gate 时，也要相应使用 16-bit code segment descriptor。也就是在 gate descriptor 中的 selector 要使用 16-bit code segment selector。...
What is the difference between native code, machine code and assembly code?
...ece of metal that does the actual work) understands and executes directly. All other code must be translated or transformed into machine code before your machine can execute it.
Native code: This term is sometimes used in places where machine code (see above) is meant. However, it is also sometimes...