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How do I replace NA values with zeros in an R dataframe?

...the complete results. If you are struggling with massive dataframes, data.table is the fastest option of all: 40% faster than the standard Base R approach. It also modifies the data in place, effectively allowing you to work with nearly twice as much of the data at once. A clustering of other he...
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How should I choose an authentication library for CodeIgniter? [closed]

... set Very good documentation Simple and elegant database design (just 4 DB tables) Most features are optional and easily configured Language file support reCAPTCHA supported Hooks into CI's validation system Activation emails Login with email, username or both (configurable) Unactivated accounts aut...
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MySQL show current connection info

...7 min 16 sec Threads: 1 Questions: 21 Slow queries: 0 Opens: 33 Flush tables: 1 Open tables: 26 Queries per second avg: 0.48 -------------- mysql> share | improve this answer | ...
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How to add a footer to a UITableView in Storyboard

... You can just drag a view to the bottom area of the tableView. You'll see in the hierarchy that it will be a subview of the tableview. You can then drag subviews such as labels and buttons there, adjust the height, etc. ...
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iOS 7 TableView like in Settings App on iPad

I want to have a group UITableView with the style same like the iPad Settings application Detail view for iOS 7 . 15 Ans...
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What does SQL clause “GROUP BY 1” mean?

...d name, you may also group by ordinal, or position of the field within the table. 1 corresponds to the first field (regardless of name), 2 is the second, and so on. This is generally ill-advised if you're grouping on something specific, since the table/view structure may change. Additionally, it ma...
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Large Object Heap Fragmentation

...is is a very interesting lead, thanks. Completely forgot about the intern table. I know one of our developers is a keen interner so this is definitely something I shall investigate. – Paul Ruane Mar 27 '09 at 10:34 ...
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Looping through a hash, or using an array in PowerShell

I'm using this (simplified) chunk of code to extract a set of tables from SQL Server with BCP . 7 Answers ...
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How do I perform an insert and return inserted identity with Dapper?

... is simply: var id = connection.QuerySingle<int>( @" INSERT INTO [MyTable] ([Stuff]) VALUES (@Stuff); SELECT CAST(SCOPE_IDENTITY() as int)", new { Stuff = mystuff}); Note that on more recent versions of SQL Server you can use the OUTPUT clause: var id = connection.QuerySingle<int>( @...
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Naming convention for unique constraint

...rimary key and foreign key have commonly used and obvious conventions ( PK_Table and FK_Table_ReferencedTable , respectively). The IX_Table_Column naming for indexes is also fairly standard. ...