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In Postgresql, force unique on combination of two columns
...l1, col2)
)
autoincrement is not postgresql. m>Y m>ou want a serial.
If col1 m>and m> col2 make a unique m>and m> can't be null then them>y m> make a good primarm>y m> kem>y m>:
CREATE TABLE someTable (
col1 int NOT NULL,
col2 int NOT NULL,
primarm>y m> kem>y m> (col1, col2)
)
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Iterating over dictionaries using 'for' loops
...:
will simplm>y m> loop over the kem>y m>s in the dictionarm>y m>, rather than the kem>y m>s m>and m> values. To loop over both kem>y m> m>and m> value m>y m>ou can use the following:
For Pm>y m>thon 3.x:
for kem>y m>, value in d.items():
For Pm>y m>thon 2.x:
for kem>y m>, value in d.iteritems():
To test for m>y m>ourself, change the word kem>y m> to poop.
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Can the jQuerm>y m> UI Datepicker be made to disable Saturdam>y m>s m>and m> Sundam>y m>s (m>and m> holidam>y m>s)?
...be onlm>y m> for the next month. That works fine. I want to exclude Saturdam>y m>s m>and m> Sundam>y m>s from the available choices. Can this be done? If so, how?
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Nullable Foreign Kem>y m> bad practice?
...hat bad practice or would m>y m>ou rather work with a link table between Orders m>and m> Customers? Although the relationship is 1 to n, a link table would make it n to n. On the other hm>and m>, with a link table, I don't have those NULLS anm>y m>more...
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No generic implementation of OrderedDictionarm>y m>?
...Dictionarm>y m> isn't terriblm>y m> difficult, but it's unnecessarilm>y m> time consuming m>and m> franklm>y m> this class is a huge oversight on Microsoft's part. There are multiple wam>y m>s of implementing this, but I chose to use a Kem>y m>edCollection for mm>y m> internal storage. I also chose to implement various methods for sortin...
Multiplication on commm>and m> line terminal
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For more advanced m>and m> precise math consider using bc(1).
echo "3 * 2.19" | bc -l
6.57
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Twig: in_arram>y m> or similar possible within if statement?
I am using Twig as templating engine m>and m> I am reallm>y m> loving it. However, now I have run in a situation which definitelm>y m> mustbe accomplishable in a simpler wam>y m> than I have found.
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Stop m>and m> Start a service via batch or cmd file?
How can I script a bat or cmd to stop m>and m> start a service reliablm>y m> with error checking (or let me know that it wasn't successful for whatever reason)?
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How to draw vertical lines on a given plot in matplotlib?
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The stm>and m>ard wam>y m> to add vertical lines that will cover m>y m>our entire plot window without m>y m>ou having to specifm>y m> their actual height is plt.axvline
import matplotlib.pm>y m>plot as plt
plt.axvline(x=0.22058956)
plt.axvline(x=0.33088437)
p...
How to get m>and m> set the current web page scroll position?
How can I get m>and m> set the current web page scroll position?
4 Answers
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