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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...
Visual Studio refuses to forget breakpoints?
...
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...
How to enable NSZombie in Xcode?
...cheme".
To edit the scheme and turn on zombies:
In the "Product" menu, select "Edit Scheme".
Go to the "Run Foo.app" stage in the left panel, and the "Arguments" tab on the right.
Add NSZombieEnabled to the "Environment Variables" section and set the value to YES, as you could in Xcode 3.
In...
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.
...
Remove/Add Line Breaks after Specific String using Sublime Text
...ight Arrow > line break
The important part being Control+Command+G to select all matches.
Once you've selected the text you're looking for, you can use the provided multiple cursors to do whatever text manipulation you want.
Protip: you can manually instantiate multiple cursors by using Comman...
Possible to iterate backwards through a foreach?
...inq can help you.
A Linq extension method using anonymous types with Linq Select to provide a sorting key for Linq OrderByDescending;
public static IEnumerable<T> Invert<T>(this IEnumerable<T> source)
{
var transform = source.Select(
(o, i) => new
...
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.
...
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
...
MySQL: Order by field size/length
...
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...