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Finding duplicate rows in SQL Server
...abase of organizations, and there are many duplicate rows. I want to run a select statement to grab all of these and the amount of dupes, but also return the ids that are associated with each organization.
...
Could not locate Gemfile
... thor (0.15.4)
Using railties (3.2.11)
Using jquery-rails (2.0.3)
Using mysql2 (0.3.11)
Using net-ldap (0.3.1)
Using ruby-openid (2.1.8)
Using rack-openid (1.3.1)
Using bundler (1.2.3)
Using rails (3.2.11)
Using rmagick (2.13.1)
Your bundle i
...
How to fix: “UnicodeDecodeError: 'ascii' codec can't decode byte”
...quire a little configuration. Always use Unicode strings for SQL queries.
MySQL
In the connection string add:
charset='utf8',
use_unicode=True
E.g.
>>> db = MySQLdb.connect(host="localhost", user='root', passwd='passwd', db='sandbox', use_unicode=True, charset="utf8")
PostgreSQL
Ad...
Equivalent of varchar(max) in MySQL?
What is the equivalent of varchar(max) in MySQL?
6 Answers
6
...
Create code first, many to many, with additional fields in association table
...OfMembers = context.Members
.Where(m => m.LastName == "Smith")
.SelectMany(m => m.MemberComments.Select(mc => mc.Comment))
.ToList();
... or ...
var commentsOfMembers = context.MemberComments
.Where(mc => mc.Member.LastName == "Smith")
.Select(mc => mc.Comment)
...
What guarantees are there on the run-time complexity (Big-O) of LINQ methods?
...).
Distinct, GroupBy Join, and I believe also the set-aggregation methods (Union, Intersect and Except) use hashing, so they should be close to O(N) instead of O(N²).
Contains checks for an ICollection implementation, so it may be O(1) if the underlying collection is also O(1), such as a HashSet<...
Is it possible to group projects in Eclipse?
...You define a working set and then add some projects to it. Later you could select a working set and only the projects you selected earlier are shown in project explorer.
Simpl grouping to reduce clutter.
http://help.eclipse.org/galileo/index.jsp?topic=/org.eclipse.platform.doc.user/concepts/cworkse...
Is String.Format as efficient as StringBuilder
...var referToTheComputedValuesSoCompilerCantOptimiseTheLoopsAway= concatkeys.Union(stringbuilderkeys).Union(cachedsbkeys).Union(formatkeys).LastOrDefault(x=>x[1]=='-');
Console.WriteLine(referToTheComputedValuesSoCompilerCantOptimiseTheLoopsAway);
...
PostgreSQL query to list all table names?
...
What bout this query (based on the description from manual)?
SELECT table_name
FROM information_schema.tables
WHERE table_schema='public'
AND table_type='BASE TABLE';
share
|
im...
how to concatenate two dictionaries to create a new one in Python? [duplicate]
...ems() for d in (d1, d2, d3)))
and:
from itertools import chain
def dict_union(*args):
return dict(chain.from_iterable(d.items() for d in args))
Python 2.6 & 2.7
from itertools import chain
dict(chain.from_iterable(d.iteritems() for d in (d1, d2, d3))
Output:
>>> from iterto...