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MySQL - UPDATE query based on SELECT Query
...first form (update with join) is going to be a lot more efficient than the second. The first would do a single join, whereas the second would execute the select query for every row of tableA.
– ColinM
Nov 8 '12 at 17:54
...
Bash tool to get nth line from a file
...t = 0
real 1m16.583s
This code ran in 00:01:16.583, which is only ~1 second slower, but still not an improvement on the baseline. At this rate if the exit command had been excluded it would have probably taken around ~76 minutes to read the entire file!
Perl
I ran the existing Perl solution ...
I need a Nodejs scheduler that allows for tasks at different intervals [closed]
...t allows to run tasks using Cron patterns e.g.
'* * * * * *' - runs every second
'*/5 * * * * *' - runs every 5 seconds
'10,20,30 * * * * *' - run at 10th, 20th and 30th second of every minute
'0 * * * * *' - runs every minute
'0 0 * * * *' - runs every hour (at 0 minutes and 0 seconds)
But also ...
How to use count and group by at the same select statement
... are not optimal.
mysql> flush status;
Query OK, 0 rows affected (0.00 sec)
SELECT province, total_cities
FROM ( SELECT DISTINCT province FROM canada ) AS provinces
CROSS JOIN ( SELECT COUNT(*) total_cities FROM canada ) AS tot;
+---------------------------+--------------+
...
Quick Sort Vs Merge Sort [duplicate]
...nitialized up front with a random 64-bit number N, and the pivot for every section is at index N mod SectionSize, then the probability of the algorithm demonstrating any complexity C where C is worse than O(n log n) exponentially decreases as the input size grows.
– Sam Harwell...
Inserting a PDF file in LaTeX
...age basis (1 each page) and use newpage between each page e,g,
\appendix
\section{Quiz 1}\label{sec:Quiz}
\begin{figure}[htp] \centering{
\includegraphics[scale=0.82]{quizz.pdf}}
\caption{Experiment 1}
\end{figure}
\newpage
\section{Sample paper}\label{sec:Sample}
\begin{figure}[htp] \centering{...
Create a date from day month and year with T-SQL
...ch is an integer representing the number of days since 1 Jan 1900, and the second part is a decimal fraction representing the fractional portion of one day (for the time) --- So the integer value 0 (zero) always translates directly into Midnight morning of 1 Jan 1900...
or, thanks to suggestion fr...
How do I select an entire row which has the largest ID in the table?
...le);" query over a table of 114 rows while this query took exactly 0.0004 sec every time while the second query took from 0.0007 to 0.0010 secs I repeated this several times
– prabhjot
Jun 5 '17 at 10:27
...
What is considered a good response time for a dynamic, personalized web application? [closed]
...out the same for thirty years [Miller 1968; Card et al. 1991]:
0.1 second is about the limit for having the user feel that the system is reacting instantaneously, meaning that no special feedback is necessary except to display the result.
1.0 second is about the limit for the user's flow o...
Displaying a message in iOS which has the same functionality as Toast in Android
...is, I need to display a message which is dismissed automatically after few seconds. This is similar to the functionality of the Toast class in the Android environment.
...