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How do I add indices to MySQL tables?
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ALTER TABLE `table` ADD INDEX `product_id_index` (`product_id`)
Never compare integer to strings in MySQL. If id is int, remove the quotes.
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How do I read image data from a URL in Python?
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HELP, IOError: cannot identify image file <_io.BytesIO object at 0x7fb91b6a29b0> my url is: ...model=product.template&id=16&field=image_medium
– С. Дэлгэрцэцэг
Sep 3 '18 at 12:43
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Add legend to ggplot2 line plot
...range your data frame
library(reshape2)
dd = melt(dd_sub, id=c("fecha"))
All that's left is a simple ggplot command:
ggplot(dd) + geom_line(aes(x=fecha, y=value, colour=variable)) +
scale_colour_manual(values=c("red","green","blue"))
Example plot
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I can't install python-ldap
...n order to compile the Python module. If you're on Ubuntu, the package is called libldap2-dev.
Debian/Ubuntu:
sudo apt-get install libsasl2-dev python-dev libldap2-dev libssl-dev
RedHat/CentOS:
sudo yum install python-devel openldap-devel
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Storing Images in PostgreSQL
...we see that image sizes, and number of images, are growing and growing, in all applications...
We need some distinction between "original image" and "processed image", like thumbnail.
As Jcoby's answer says, there are two options, then, I recommend:
use blob (Binary Large OBject): for original imag...
What does DIM stand for in Visual Basic and BASIC?
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Dim originally (in BASIC) stood for Dimension, as it was used to define the dimensions of an array.
(The original implementation of BASIC was Dartmouth BASIC, which descended from FORTRAN, where DIMENSION is spelled out.)
Nowadays, D...
IF… OR IF… in a windows batch file
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The zmbq solution is good, but cannot be used in all situations, such as inside a block of code like a FOR DO(...) loop.
An alternative is to use an indicator variable. Initialize it to be undefined, and then define it only if any one of the OR conditions is true. Then use ...
What is the largest Safe UDP Packet Size on the Internet
...rmation that you may not have anticipated. A 512-byte UDP payload is generally considered to do that, although even that does not leave quite enough space for a maximum size IP header.
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What are the benefits of functional programming? [closed]
...bel refers to a version of this array where this function has been done on all the elements."
Functional programming moves more basic programming ideas into the compiler, ideas such as list comprehensions and caching.
The biggest benefit of Functional programming is brevity, because code can be mo...
How to solve “Fatal error: Class 'MySQLi' not found”?
...amazon linux, it would be something like sudo yum install php56-mysqlnd.x86_64 (pick the one matching to which version of php you have installed)
– auspicious99
Dec 3 '18 at 10:46
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