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What is your most productive shortcut with Vim?
...e used as subjects for other "statements."
So, one way to cut an arbitrary selection of text would be to drop a mark (I usually use 'a' as my "first" mark, 'z' as my next mark, 'b' as another, and 'e' as yet another (I don't recall ever having interactively used more than four marks in 15 years of u...
How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...
LINQ's Distinct() on a particular property
...
(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)
{
HashSet<TKey> seenKeys = new HashSet<TKey>();
foreach (TSource element in source)
{
if (seenKeys.Add(keySelector(element)))
{
yield return element;
}
...
When should I use C++14 automatic return type deduction?
...n expressions they are usually implicit but we can make them explicit with casts". C++11 and C++1y introduce type deduction tools so that you can leave out the type in new places.
Sorry, but you're not going to solve this up front by making general rules. You need to look at particular code, and de...
“No backupset selected to be restored” SQL Server 2012
...n I try with the UI approach ("Restore"), I get message @ top No backupset selected to be restored.
– The Red Pea
Apr 27 '17 at 16:50
...
python-pandas and databases like mysql
...a_conn = cx_Oracle.connect('your_connection_string')
df_ora = pd.read_sql('select * from user_objects', con=ora_conn)
print 'loaded dataframe from Oracle. # Records: ', len(df_ora)
ora_conn.close()
And here is the equivalent example for MySQLdb:
import MySQLdb
mysql_cn= MySQLdb.connect(host='...
Can I write a CSS selector selecting elements NOT having a certain class or attribute?
I would like to write a CSS selector rule that selects all elements that don't have a certain class. For example, given the following HTML:
...
right click context menu for datagridview
...d like to rightclick on a row and have a menu pop up. Then i would like to select things such as copy, validate, etc
7 Answ...
What is the error “Every derived table must have its own alias” in MySQL?
...er), which can the be used to refer to it in the rest of the outer query.
SELECT ID FROM (
SELECT ID, msisdn FROM (
SELECT * FROM TT2
) AS T
) AS T
In your case, of course, the entire query could be replaced with:
SELECT ID FROM TT2
...
Install MySQL on Ubuntu without a password prompt
...
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password password your_password'
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password_again password your_password'
sudo apt-get -y install ...