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Insert, on duplicate update in PostgreSQL?
...it would be much slower, because each upsert would be its' own individual call into the database.
– baash05
Mar 1 '12 at 0:27
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Group by multiple columns in dplyr, using string vector input
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Does the call to one_of() do anything here? I think it is redundant in this context, as the expression is wrapped in a call to vars().
– knowah
Aug 15 '19 at 14:13
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Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...:
SET @rUsername = ‘aname’ COLLATE utf8_unicode_ci; -- COLLATE added
CALL updateProductUsers(@rUsername, @rProductID, @rPerm);
Option 2: add COLLATE to the WHERE clause:
CREATE PROCEDURE updateProductUsers(
IN rUsername VARCHAR(24),
IN rProductID INT UNSIGNED,
IN rPerm VARCHAR(16...
Adding a parameter to the URL with JavaScript
In a web application that makes use of AJAX calls, I need to submit a request but add a parameter to the end of the URL, for example:
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How do I write the 'cd' command in a makefile?
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It is actually executing the command, changing the directory to some_directory, however, this is performed in a sub-process shell, and affects neither make nor the shell you're working from.
If you're looking to perform more tasks wit...
NoClassDefFoundError: android.support.v7.internal.view.menu.MenuBuilder
....v7.** { *; }
-keep interface android.support.v7.** { *; }
with this:
# Allow obfuscation of android.support.v7.internal.view.menu.**
# to avoid problem on Samsung 4.2.2 devices with appcompat v21
# see https://code.google.com/p/android/issues/detail?id=78377
-keep class !android.support.v7.inter...
Java “lambda expressions not supported at this language level”
...: android { compileOptions { sourceCompatibility JavaVersion.VERSION_1_8 targetCompatibility JavaVersion.VERSION_1_8 } }
– BaDo
Sep 25 '15 at 2:30
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How can I use Spring Security without sessions?
...n block these assets on the first load because "the URL contained a potentially malicious String ';'".
– workerjoe
Mar 5 at 17:36
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What is the most “pythonic” way to iterate over a list in chunks?
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Finally got a chance to play around with this in a python session. For those who are as confused as I was, this is feeding the same iterator to izip_longest multiple times, causing it to consume successive values of the same seq...
Commenting in a Bash script inside a multiline command
...utput MYSQLDUMP file
cat ${MYSQLDUMP} | \
# simplify the line
sed '/created_at/d' | \
# create some newlines
tr ",;" "\n" | \
# use some sed magic
sed -e 's/[asbi]:[0-9]*[:]*//g' -e '/^[{}]/d' -e 's/""//g' -e '/^"{/d' | \
# more magic
sed -n -e '/^"/p' -e '/^print_value$/,/^option_id$/p' | \
# even ...