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String concatenation in MySQL
...most DBMSs use of + or || for concatenation. It uses the CONCAT function:
SELECT CONCAT(first_name, " ", last_name) AS Name FROM test.student
As @eggyal pointed out in comments, you can enable string concatenation with the || operator in MySQL by setting the PIPES_AS_CONCAT SQL mode.
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What is a “batch”, and why is GO used?
...add a column to a table, then it should be in its own batch.
If you try to SELECT the new column in the same batch it fails because at parse/compile time the column does not exist.
GO is used by the SQL tools to work this out from one script: it is not a SQL keyword and is not recognised by the eng...
In VIM, how do I break one really long line into multiple lines?
... format the line that {motion} moves over
{Visual}gq % format the visually selected area
gqq % format the current line
...
I'd suggest you check out :help gq and :help gw.
Also setting textwidth (tw) will give you auto line break when exceeded during typing. It is used in gq too, though if...
Folder is locked and I can't unlock it
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Right click on your Subversion working directory folder, and select TortoiseSVN->Clean Up from the Context Menu. This will recurse it's way through your working directory and cleanup any incomplete actions, remove the local locks (which is different from using Subversion locking of ...
MySQL: Order by field size/length
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SELECT * FROM TEST ORDER BY LENGTH(description) DESC;
The LENGTH function gives the length of string in bytes. If you want to count (multi-byte) characters, use the CHAR_LENGTH function instead:
SELECT * FROM TEST ORDER BY...
Visual Studio refuses to forget breakpoints?
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Try this select the Breakpoints toolbar item from the Debug toolbar. This brings up the Breakpoints window. From this window, you can view all breakpoints in the application. Here, you select and clear the breakpoint by clicking the D...
autolayout - make height of view relative to half superview height
...lso need to setup bottom, left, and right constraints, like normal)
. Then select the constraint and navigate to the Attribute inspector:
Then you can adjust the multiplier. If you want it 50% of the super view leave it at 1, since it is aligned per the super's center. This is also a great way to...
Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?
... up the firstname field as shown.
http://localhost:8983/solr/collection1/select?q=firstname:john^2&lastname:john
As you can see, firstname field is boosted up with a score of 2.
More on SolrRelevancy
searching and indexing speed
The speed is unbelievably fast and no compromise o...
Should I use the datetime or timestamp data type in MySQL?
...o with the native format. You can do calculations within MySQL that way
("SELECT DATE_ADD(my_datetime, INTERVAL 1 DAY)") and it is simple to change the format of the value to a UNIX timestamp ("SELECT UNIX_TIMESTAMP(my_datetime)") when you query the record if you want to operate on it with PHP.
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Why does installing Nokogiri on Mac OS fail with libiconv is missing?
...ed to install xCode command tools to allow you to install libiconv.
xcode-select --install
then install a newer version of libiconv
brew install libiconv
then install your gem
gem install nokogiri -- --with-iconv-dir=/usr/local/Cellar/libiconv/1.14
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