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SQLite add Primary Key
...It's weird that you can't add a PK after table creation but you can add an index (CREATE UNIQUE INDEX pkName ON tableName(columnName)) when DB frameworks like MS SQL's SMO actually make you add a PK after the table has been created!
– SteveCinq
Aug 31 '17 at 18...
Traverse a list in reverse order in Python
...versed(a):
... print(i)
...
baz
bar
foo
To also access the original index, use enumerate() on your list before passing it to reversed():
>>> for i, e in reversed(list(enumerate(a))):
... print(i, e)
...
2 baz
1 bar
0 foo
Since enumerate() returns a generator and generators ca...
Get index of selected option with jQuery
I'm a little bit confused about how to get an index of a selected option from a HTML <select> item.
7 Answers
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pandas three-way joining multiple dataframes on columns
...
This didn't quite work for my dfs with column multi indexes (it was injecting the 'on' as a column which worked for the first merge, but subsequent merges failed), instead I got it to work with: df = reduce(lambda left, right: left.join(right, how='outer', on='Date'), dfs)
...
“git diff” does nothing
...t diff is the list of changes which have not been committed / added to the index. If there are no changes, then there is no output.
git diff [--options] [--] […]
This form is to view the changes you made relative to the index (staging area for the next commit). In other words, the differe...
Error message “Forbidden You don't have permission to access / on this server” [closed]
... answer instead
Many scenarios can lead to 403 Forbidden:
A. Directory Indexes (from mod_autoindex.c)
When you access a directory and there is no default file found in this directory
AND Apache Options Indexes is not enabled for this directory.
A.1. DirectoryIndex option example
DirectoryInde...
Git stash uncached: how to put away all unstaged changes?
...d files you can add the -u flag
The full command becomes git stash --keep-index -u
And here's a snippet from the git-stash help
If the --keep-index option is used, all changes already added to the
index are left intact.
If the --include-untracked option is used, all untracked files are
...
Why use 'git rm' to remove a file instead of 'rm'?
...tep.
You can also use git rm --cached which will remove the file from the index (staging it for deletion on the next commit), but keep your copy in the local file system.
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JavaScript closure inside loops – simple practical example
...ferently than var-based variables. For example, in a loop with a let-based index, each iteration through the loop will have a new variable i with loop scope, so your code would work as you expect. There are many resources, but I'd recommend 2ality's block-scoping post as a great source of informatio...
Should you always favor xrange() over range()?
... is an object in Python2. I think what you meant to say is that you can do index-based comprehension (if that makes sense) better with range as opposed to xrange. Range is handy very seldom, I think
– dylnmc
Nov 12 '14 at 0:34
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