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how to check the dtype of a column in python pandas
...ions to treat numeric columns and string columns. What I am doing now is really dumb:
6 Answers
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Oracle Differences between NVL and Coalesce
...ented differently.
NVL always evaluates both arguments, while COALESCE usually stops evaluation whenever it finds the first non-NULL (there are some exceptions, such as sequence NEXTVAL):
SELECT SUM(val)
FROM (
SELECT NVL(1, LENGTH(RAWTOHEX(SYS_GUID()))) AS val
FROM dual
...
What is the best way to detect a mobile device?
...igator.userAgent.toLowerCase()));
Now $.browser will return "device" for all above devices
Note: $.browser removed on jQuery v1.9.1. But you can use this by using jQuery migration plugin Code
A more thorough version:
var isMobile = false; //initiate as false
// device detection
if(/(android|b...
PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
.... Instead of asking my question in bulk, I preferred to break it up into small parts so that it is easy for novice users to understand as well. So my question(s):
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How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?
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You are so close! All you need to do is select BOTH the home and its max date time, then join back to the topten table on BOTH fields:
SELECT tt.*
FROM topten tt
INNER JOIN
(SELECT home, MAX(datetime) AS MaxDateTime
FROM topten
GR...
How can I calculate the difference between two dates?
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Not all days have 86400 seconds. For a trivial example that's fine but it's not a good idea in the real world. DST changes, leap seconds, etc can all mess with it. NSCalendar can tell you how many seconds are in a given day.
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How to get week number in Python?
...ear (Sunday as the first day of the week) as a zero padded decimal number. All days in a new year preceding the first Sunday are considered to be in week 0. Examples: 00, 01, …, 53
%W - Week number of the year (Monday as the first day of the week) as a decimal number. All days in a new year p...
Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
...swered May 26 '11 at 2:40
James AllmanJames Allman
37.4k99 gold badges5252 silver badges6969 bronze badges
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Finding the number of days between two dates
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What about leap seconds? Not all days have exactly 24*60*60 seconds. This code might be sufficient for practical purposes but it's not exact in sone extremely rare edge cases.
– Benjamin Brizzi
Aug 1 '12 at 8:15
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How to get disk capacity and free space of remote computer
...20 vs. 10^6. It should indeed be written 1MiB (with proper case) but is usually shown in lower case, without th "i". See Mebibyte.
– Matthieu
Mar 3 at 12:09
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