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How to retrieve form values from HTTPPOST, dictionary or?
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CASCADE DELETE just once
...you want to cascade.
DELETE FROM some_child_table WHERE some_fk_field IN (SELECT some_id FROM some_Table);
DELETE FROM some_table;
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Using Java 8's Optional with Stream::flatMap
... new Java 8 stream framework and friends make for some very concise java code, but I have come across a seemingly-simple situation that is tricky to do concisely.
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Remove border radius from Select tag in bootstrap 3
...s gone, you have to add back in the arrow that visually differentiates the select from the input. Note: appearance is not supported in IE.
Working example: https://jsfiddle.net/gs2q1c7p/
select:not([multiple]) {
-webkit-appearance: none;
-moz-appearance: none;
background-positio...
Does pandas iterrows have performance issues?
...se groupby to avoid repeated comparing of values.
Use to_records to access raw numpy.records objects.
Don't operate on DataFrame until you have compiled all the data.
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How to get the contents of a webpage in a shell variable?
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You can use curl or wget to retrieve the raw data, or you can use w3m -dump to have a nice text representation of a web page.
$ foo=$(w3m -dump http://www.example.com/); echo $foo
You have reached this web page by typing "example.com", "example.net","example.org" o...
Rank function in MySQL
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One option is to use a ranking variable, such as the following:
SELECT first_name,
age,
gender,
@curRank := @curRank + 1 AS rank
FROM person p, (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initializatio...
Get records with max value for each group of grouped SQL results
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There's a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. T...
Get list of databases from SQL Server
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Execute:
SELECT name FROM master.sys.databases
This the preferred approach now, rather than dbo.sysdatabases, which has been deprecated for some time.
Execute this query:
SELECT name FROM master.dbo.sysdatabases
or if you pref...
Clear form fields with jQuery
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A small tip: this selector won't select input elements that are relying on the implicit type=text, you must explicitly include the type=text on your markup. That may be obvious, but it wasn't to me, just now :-)
– Elbin
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