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What are the options for storing hierarchical data in a relational database? [closed]
...st.
+-------------+----------------------+--------+-----+-----+
| category_id | name | parent | lft | rgt |
+-------------+----------------------+--------+-----+-----+
| 1 | ELECTRONICS | NULL | 1 | 20 |
| 2 | TELEVISIONS | 1 | 2 | ...
cannot convert data (type interface {}) to type string: need type assertion
...]i to its value type, we have to do it individually:
// var items []i
for _, item := range items {
value, ok := item.(T)
dosomethingWith(value)
}
Performance
As for performance, it can be slower than direct access to the actual value as show in this stackoverflow answer.
...
How to fix 'sudo: no tty present and no askpass program specified' error?
...environment is configured to use, which very well could be (and should be ^_^) vi.
– Matt Styles
May 29 '15 at 22:59
8
...
error: Unable to find vcvarsall.bat
...ib\distutils\distutils.cfg to be:
[build]
compiler=mingw32
Now run easy_install.exe amara.
Make sure environment is set by opening a new cmd.exe.
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How do you remove a Cookie in a Java Servlet
... seems to work consistently across all browsers.
– ug_
Oct 27 '13 at 9:29
5
I'm not sure you shou...
.NET data structures: ArrayList, List, HashTable, Dictionary, SortedList, SortedDictionary — Speed,
... edited Feb 23 '17 at 11:59
marc_s
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answered Sep 24 '08 at 18:00
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Multiple inheritance for an anonymous class
...ited Jun 5 '14 at 14:45
aspiring_sarge
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answered May 1 '11 at 13:04
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What's the difference between MyISAM and InnoDB? [duplicate]
...e differences between InnoDB and MyISAM. But yes, InnoDB behavior with AUTO_INCREMENT is a difference, and one that we have to account for if we are going to use AUTO_INCREMENT, and if we are dependent on some behavior that isn't supported. This difference could be considered a disadvantage; perhaps...
Switch branch names in git
...ing else, then rename your new branch to master:
git branch -m master crap_work
git branch -m previous_master master
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SQL query to get all values a enum can have
...
If you want an array:
SELECT enum_range(NULL::myenum)
If you want a separate record for each item in the enum:
SELECT unnest(enum_range(NULL::myenum))
Additional Information
This solution works as expected even if your enum is not in the default sc...