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Top Forums Shell Programming and Scripting Select record with MAX value in MySQL Post 302433719 by chebarbudo on Wednesday 30th of June 2010 10:26:31 AM
Old 06-30-2010
Time is indeed an issue given the fast growing number of uploaded files.
I isolated one operation: retrieve the file id on 300,000 records.
With a massive update, it takes about 75 seconds.
With a one by one update, I started clocking more than an hour ago and it's not even finished.

Anyway, thank you very much for helping me go deeper in the structure of my database. It was very interesting.

Cheers
Santiago

---------- Post updated at 15:11 ---------- Previous update was at 15:06 ----------

Usually there's a way to reward people who help with bits.
I can't find the button anymore. Do you know where it is?

---------- Post updated at 15:24 ---------- Previous update was at 15:11 ----------

I stopped the query because I needed my CPU ;o)
Trying to extrapolate the number of records already processed, I evaluated that the one by one update is around 2,000 times longer than the massive update.

---------- Post updated at 15:26 ---------- Previous update was at 15:24 ----------

I forgot to mention that I think the incredible difference is certainly due to the well chosen indexes you told me to create.
 

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ROOTTAIL(1)						      General Commands Manual						       ROOTTAIL(1)

NAME
root-tail - print text directly to X11 root window SYNOPSIS
root-tail [-g|--geometry GEOMETRY] [-fn|--font FONTSPEC] [--color color] [--reload SEC COMMAND] [--shade] [--outline] [--minspace] [--noflicker] [-f|--fork] [--reverse] [--whole] [--partial] [--update] [--cont STRING] [--wordwrap] [--justify] [--noinitial] [--frame] [-id ID] [-i|--interval SECONDS] [-V] file1[,color[,desc]] [file2[,color[,desc]]] DESCRIPTION
Displays a given file anywhere on your X11 root window, i.e. it is kind of tail -f for multiple files using your desktop background as out- put window. All non-option arguments on the command line are files to be logged. A null desc (example: "/var/log/messages,red,") will prevent the printing of a description and the []'s. General Options --color COLOR Use COLOR as default. --font | -fn FONTSPEC Use font FONTSPEC. This can be either a fixed width font like -fn fixed or any font using -fn '-*-*-*-*-*-*-*-*-*-*-*-*-*-*' with the appropriate fields filled out (see xfontsel). Specifying a different FONTSPEC before each filename will cause each file to be displayed in a different font. -f | --fork Forks to the background. --reverse Display the files in reverse order, with the newest lines at the top. --whole Only display whole lines. If the last line of a file doesn't yet end with a newline character then wait until it does before dis- playing it. This is the default if more than one file is being displayed. --partial This is the opposite of the --whole option (see above). It displays lines even if they don't yet have a newline at the end. This is the default if only one file is being displayed. --update Update partial lines 'in place' if they are still on the screen when they are updated in their files. Using --update automatically turns on --partial. --cont STRING When partial lines are broken into two lines in the display, prefix the 2nd line with STRING. Defaults to "|| ". Specify the "--whole" argument to ensure partial lines are never displayed, or specify "--update" to attempt to "repair" broken lines in-place. --cont-color COLOR Use COLOR when displaying the continuation string (as optionally specified with the --cont option above). --wordwrap The default behaviour is to fit as much as possible onto each line of output, even if this means splitting a word between one line and the next. The --wordwrap argument splits lines at spaces if possible. --justify After wrapping long lines, attempt to justify the text to produce a smooth right-hand margin. Implies --wordwrap. --reload SEC COMMAND Re-display the file(s) and run COMMAND every SEC seconds. The default is to never re-display the file(s). --shade Add black shading to the font. --outline Add a black outline to the font (making redraws quite a bit slower). --minspace Use minimum linespace even when using shading or outlining. This might result in leftover pixels (dependign on font and logfile con- tent). --noflicker Use slower but flicker-free update. --noinitial Don't display the end of the file(s) initially. -id ID Use the given window ID for output instead of the root window. -i | --interval SECONDS Use the specified sleeping interval between checks instead of the default 2.4 seconds. Fractional values are OK. -V Print version information. --frame Draw a frame around the selected area. This is useful when trying to find the perfect geometry. EXAMPLE
root-tail -g 800x250+100+50 -font 10x20 /var/log/messages,green -font 12x24 /var/log/secure,red,'ALERT' BUGS
Some desktop environments open a virtual root window and make it difficult to share it. If you cannot see anything after starting root- tail, try to find a setting "allow programs on desktop" or similar, or manually specify a window id. Should you happen to find any bugs please fix them and send me a diff. NOTE: This program was modified by Marc Lehmann <pcg@goof.com>, who couldn't reach the original author. Please direct bug-reports etc. to pcg@goof.com. http://root-tail.plan9.de/ 4.2 Berkeley Distribution 2004-03-27 ROOTTAIL(1)
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