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Adding a column to an existing table in a Rails migration
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@neeraj you probably have the answer by now but for other seekers, yes you can as in e.g. t.string :column_x, limit: 10, after: :column_y (for Rails 4 at least)
– 244an
May 15 '19 at 19:59
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Split string on whitespace in Python [duplicate]
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Also good to know is that if you want the first word only (which means passing 1 as second argument), you can use None as the first argument: s.split(None, 1)
– yak
Nov 13 '11 at 19:00
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Why Maven uses JDK 1.6 but my java -version is 1.7
...n -s /Library/Java/JavaVirtualMachines/jdk1.8.0.jdk/Contents/ CurrentJDK
Now it shall work immediately.
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Trigger 404 in Spring-MVC controller?
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In your case it sounds fine, but I don't know that I'd recommend the exceptions found in the link you provided to handle all cases where an exception in necessary - sometimes you should make your own.
– Roy Truelove
Oct 10 '12 a...
Improve INSERT-per-second performance of SQLite
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Docs don't know a PRAGMA journal_mode NORMAL sqlite.org/pragma.html#pragma_journal_mode
– OneWorld
Jan 31 '14 at 8:52
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How to split long commands over multiple lines in PowerShell
... are using Notepad++, it will even highlight correctly as a string block.
Now, if you wanted that string to contain double quotes, too, just add them in, like this:
$myvar = "Site"
$mystring = @"
<a href="http://somewhere.com/somelocation">
Bob's $myvar
</a>
"@
You would get exactly ...
Add Foreign Key to existing table
...d an index to it..
ALTER TABLE users ADD INDEX index_name (index_column)
Now add the constraint
ALTER TABLE foreign_key_table
ADD CONSTRAINT foreign_key_name FOREIGN KEY (foreign_key_column)
REFERENCES primary_key_table (primary_key_column) ON DELETE NO ACTION
ON UPDATE CASCADE;
Note if you d...
Reset AutoIncrement in SQL Server after Delete
I've deleted some records from a table in a SQL Server database. Now the ID's go from 101 to 1200. I want to delete the records again, but I want the ID's to go back to 102. Is there a way to do this in SQL Server?
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Running karma after installation results in 'karma' is not recognized as an internal or external com
...ht find it useful to install karma-cli globally:
npm install -g karma-cli
Now, check that karma was installed by typing:
which karma //echo something like: /usr/local/bin/karma
and check that karma server is working (ctr+c to quit):
karma start
You can also check that karma was installed by goi...
SQL query to group by day
...SISTED
ALTER TABLE dbo.Sales
ADD SaleDay AS DAY(Created) PERSISTED
and now you could easily group by, order by etc. by day, month or year of the sale:
SELECT SaleDay, SUM(Amount)
FROM dbo.Sales
GROUP BY SaleDay
Those calculated fields will always be kept up to date (when your "Created" date c...