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How to read a .xlsx file using the pandas Library in iPython?
...xcel:
read_excel(io, sheetname=0, header=0, skiprows=None, skip_footer=0, index_col=None, names=None, parse_cols=None, parse_dates=False, date_parser=None, na_values=None, thousands=None, convert_float=True, has_index_names=None, converters=None, true_values=None, false_values=None, engine=None, sq...
What does the KEY keyword mean?
...
Quoting from http://dev.mysql.com/doc/refman/5.1/en/create-table.html
{INDEX|KEY}
So KEY is an INDEX ;)
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Create unique constraint with null columns
...
Create two partial indexes:
CREATE UNIQUE INDEX favo_3col_uni_idx ON favorites (user_id, menu_id, recipe_id)
WHERE menu_id IS NOT NULL;
CREATE UNIQUE INDEX favo_2col_uni_idx ON favorites (user_id, recipe_id)
WHERE menu_id IS NULL;
This way,...
Usage of protocols as array types and function parameters in swift
...ment)
}
func removeElement(element: ElementType) {
if let index = find(self.protocols, element) {
self.protocols.removeAtIndex(index)
}
}
}
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Case insensitive replace
...replace(old, new, text):
idx = 0
while idx < len(text):
index_l = text.lower().find(old.lower(), idx)
if index_l == -1:
return text
text = text[:index_l] + new + text[index_l + len(old):]
idx = index_l + len(new)
return text
...
Remove characters after specific character in string, then remove substring?
...his
string input = "http://www.somesite.com/somepage.aspx?whatever";
int index = input.IndexOf("?");
if (index > 0)
input = input.Substring(0, index);
Edit: If everything after the last slash, do something like
string input = "http://www.somesite.com/somepage.aspx?whatever";
int index = ...
difference between primary key and unique key
...erent for Primary and Unique Key.
By Default:
PK creates a Clustered index and UK creates a Non Clustered Index.
PK is not null, but UK allows nulls (Note: By Default)
There can only be one and only one PK on a table, but there can be multiple UK's
You can override the default implementation ...
Does Dart support enumerations?
... print(Status.values);
Status.values.forEach((v) => print('value: $v, index: ${v.index}'));
print('running: ${Status.running}, ${Status.running.index}');
print('running index: ${Status.values[1]}');
}
[Status.none, Status.running, Status.stopped, Status.paused]
value: Status.none, in...
Ignore files that have already been committed to a Git repository [duplicate]
...repository that I added a .gitignore file to. How can I refresh the file index so the files I want ignored get ignored?
2...
What's the difference between git reset --mixed, --soft, and --hard?
...nstaged. In order to commit it, you must stage it—that is, add it to the index—using git add. When you make a commit, the changes that are committed are those that have been added to the index.
git reset changes, at minimum, where the current branch (HEAD) is pointing. The difference between --...