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Differences between INDEX, PRIMARY, UNIQUE, FULLTEXT in MySQL?
...e - which are typically implemented internally using b-trees (allowing for selecting, sorting or ranges starting from left most column) or hash tables (allowing for selection starting from left most column).
Where the other index types are general-purpose, a FULLTEXT index is specialised, in that it...
Apply multiple functions to multiple groupby columns
... group. When aggregating, g will be a Series. Passing g.index to df.ix[] selects the current group from df. I then test if column C is less than 0.5. The returned boolean series is passed to g[] which selects only those rows meeting the criteria.
In [95]: cust = lambda g: g[df.loc[g.index]['C']...
Converting an array of objects to ActiveRecord::Relation
...e clause will generate a SQL statement with IN that looks something like:
SELECT .... WHERE `my_models`.id IN (2, 3, 4, 6, ....
Keep in mind that the ordering of the array will be lost - But since your objective is only to run a class method on the collection of these objects, I assume it won't b...
Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
...heck your database transaction isolation level in the mysql cli:
mysql> SELECT @@GLOBAL.tx_isolation, @@tx_isolation, @@session.tx_isolation;
+-----------------------+-----------------+------------------------+
| @@GLOBAL.tx_isolation | @@tx_isolation | @@session.tx_isolation |
+----------------...
Difference between / and /* in servlet mapping url pattern
...tial difference between /* and / is that a servlet with mapping /* will be selected before any servlet with an extension mapping (like *.html), while a servlet with mapping / will be selected only after extension mappings are considered (and will be used for any request which doesn't match anything ...
Writing a git post-receive hook to deal with a specific branch
...anch on our server, and ignore pushes to other branches. Is it possible to select the branch from a bare repo and push only that branch to Assembla?
...
Faster s3 bucket duplication
...
If you don't mind using the AWS console, you can:
Select all of the files/folders in the first bucket
Click Actions > Copy
Create a new bucket and select it
Click Actions > Paste
It's still fairly slow, but you can leave it alone and let it do its thing.
...
How to install Hibernate Tools in Eclipse?
...bosstools/updates/stable/
Inside JBoss Web and Java EE Development folder, select Hibernate Tools
Click on Next
Once installed click on Window -> Show View -> Others. A new window pops up. Click on folder Hibernate and select Hibernate Configurations to setup a DB connection. It is possible ...
PostgreSQL - how to quickly drop a user with existing privileges
...llimoose: I really don't want the original tables to be dropped if I GRANT SELECT ON FOO TO TESTUSER and then DROP OWNED BY TESTUSER. I think you're saying that DROP OWNED BY is only dropping the grants but will not drop the object to which the grant was made. Correct?
– Andr...
Where is SQL Server Management Studio 2012?
...all the entire SQL Server package, later on in the install process you can select to only install SSMS.
– Baodad
Jul 24 '13 at 18:21
...