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How do I check the difference, in seconds, between two dates?
...tes, use total_seconds like this:
import datetime as dt
a = dt.datetime(2013,12,30,23,59,59)
b = dt.datetime(2013,12,31,23,59,59)
(b-a).total_seconds()
86400.0
#note that seconds doesn't give you what you want:
(b-a).seconds
0
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Generate random 5 characters string
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$rand = substr(md5(microtime()),rand(0,26),5);
Would be my best guess--Unless you're looking for special characters, too:
$seed = str_split('abcdefghijklmnopqrstuvwxyz'
.'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
.'0123456789!@#$%^&*()...
What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* F...
How much size “Null” value takes in SQL Server
I have a large table with say 10 columns. 4 of them remains null most of the times. I have a query that does null value takes any size or no size in bytes. I read few articles some of them are saying :
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How can I pad an int with leading zeros when using cout
...to output an int with leading zeros, so the value 1 would be printed as 001 and the value 25 printed as 025 . How can I do this?
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Pickle or json?
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edited Sep 30 '18 at 16:41
Daniel Heilper
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Change text from “Submit” on input tag
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answered Dec 23 '12 at 0:00
Ry-♦Ry-
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How to determine function name from inside a function
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You can use ${FUNCNAME[0]} in bash to get the function name.
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Only one expression can be specified in the select list when the subquery is not introduced with EXI
...(distinct dNum)
from myDB.dbo.AQ
where A_ID in
(SELECT DISTINCT TOP (0.1) PERCENT A_ID
FROM myDB.dbo.AQ
WHERE M > 1 and B = 0
GROUP BY A_ID
ORDER BY COUNT(DISTINCT dNum) DESC)
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