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Is String.Format as efficient as StringBuilder
...var referToTheComputedValuesSoCompilerCantOptimiseTheLoopsAway= concatkeys.Union(stringbuilderkeys).Union(cachedsbkeys).Union(formatkeys).LastOrDefault(x=>x[1]=='-');
Console.WriteLine(referToTheComputedValuesSoCompilerCantOptimiseTheLoopsAway);
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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<...
初创公司如何利用社交媒体实现营销效果最大化？ - 资讯 - 清泛网 - 专注C/C...
初创公司如何利用社交媒体实现营销效果最大化？今年十月，美国调查机构皮尤研究中心发布了一份研究，其中显示美国成年人中有65%都使用社交媒体网站，这意味着如果你的公司没有开通相关社交账户，那么就会失去美国三分...
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...
Escaping single quote in PHP when inserting into MySQL [duplicate]
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You should be escaping each of these strings (in both snippets) with mysql_real_escape_string().
http://us3.php.net/mysql-real-escape-string
The reason your two queries are behaving differently is likely because you have magic_quotes_gpc turned on (which you should know is a bad idea). This...
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...
Count number of records returned by group by
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You can do both in one query using the OVER clause on another COUNT
select
count(*) RecordsPerGroup,
COUNT(*) OVER () AS TotalRecords
from temptable
group by column_1, column_2, column_3, column_4
share
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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
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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.
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Equivalent of varchar(max) in MySQL?
What is the equivalent of varchar(max) in MySQL?
6 Answers
6
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