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Aggregate function in an SQL update query?
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UPDATE t1
SET t1.field1 = t2.field2Sum
FROM table1 t1
INNER JOIN (select field3, sum(field2) as field2Sum
from table2
group by field3) as t2
on t2.field3 = t1.field3
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How to sleep for five seconds in a batch file/cmd [duplicate]
...specify the timeout in seconds and the /D parameter to specify the default selection and ignore then selected choice.
The one thing that might be an issue is if the user types one of the choice characters before the timeout period elapses. A partial work-around is to obfuscate the situation -- use ...
The import javax.servlet can't be resolved [duplicate]
...ibraries tab
Click Add External JARs...
Browse to find servlet-api.jar and select it.
Click OK to update the build path.
Or, if you copy the JAR into your project:
Right-click the project, click Properties.
Choose Java Build Path.
Click Add JARs...
Find servlet-api.jar in your project and select...
jquery data selector
I need to select elements based on values stored in an element's .data() object. At a minimum, I'd like to select top-level data properties using selectors, perhaps like this:
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Find all elements on a page whose element ID contains a certain text using jQuery
... $(this).doStuff();
});
Note the asterisk '*' at the beginning of the selector matches all elements.
See the Attribute Contains Selectors, as well as the :visible and :hidden selectors.
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How to create a sequence of integers in C#?
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Linq projection with the rarely used indexer overload (i):
(new int[11]).Select((o,i) => i)
I prefer this method for its flexibilty.
For example, if I want evens:
(new int[11]).Select((item,i) => i*2)
Or if I want 5 minute increments of an hour:
(new int[12]).Select((item,i) => i*5...
get list from pandas dataframe column
...then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataF...
How to do an INNER JOIN on multiple columns
...n once by giving the joined tables an alias, as in the following example:
SELECT
airline, flt_no, fairport, tairport, depart, arrive, fare
FROM
flights
INNER JOIN
airports from_port ON (from_port.code = flights.fairport)
INNER JOIN
airports to_port ON (to_port.code = flights.tair...
How does Google's Page Speed lossless image compression work?
...om build tool which compresses images with both optipng and pngcrush, then selects the smaller file. Still, Page Speed complains about non-optimal images. So which tool do they really use?
– user123444555621
Sep 10 '12 at 7:42
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
In Pandas, when I select a label that only has one entry in the index I get back a Series, but when I select an entry that has more then one entry I get back a data frame.
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