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Convert Unix timestamp into human readable date using MySQL

... Use FROM_UNIXTIME(): SELECT FROM_UNIXTIME(timestamp) FROM your_table; See also: MySQL documentation on FROM_UNIXTIME(). share | improve this answer | follow ...
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How do I check if a SQL Server text column is empty?

I am using SQL Server 2005. I have a table with a text column and I have many rows in the table where the value of this column is not null, but it is empty. Trying to compare against '' yields this response: ...
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How do I make a list of data frames?

... data import function for read.csv as appropriate. readr::read_csv or data.table::fread will be faster, or you may also need a different function for a different file type. Either way, it's handy to name the list elements to match the files names(my_data) <- gsub("\\.csv$", "", my_files) # or, ...
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Design Pattern for Undo Engine

...e object is needed, you lookup the current definition of the object from a table. The table contains a linked list for each object that contains all the previous versions, along with information regarding which checkpoint they were active for. Implementing undo/redo is simple: Do your action and es...
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Shortcuts in Objective-C to concatenate NSStrings

...ly as pleasant as just having a concatenation operator. First, use an NSMutableString, which has an appendString method, removing some of the need for extra temp strings. Second, use an NSArray to concatenate via the componentsJoinedByString method. ...
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Order Bars in ggplot2 bar graph

...y axis and the shortest bar would be furthest. So this is kind of like the Table I have 14 Answers ...
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Proper SCSS Asset Structure in Rails

... patterns and elements @import "type.scss"; @import "forms.scss"; @import "tables.scss"; @import "patterns.scss"; And your application.scss file look like: @import "bootstrap/bootstrap.scss"; Because of the order of the imports, you can now use the variables, loaded with @import "variables.scss...
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Why use a READ UNCOMMITTED isolation level?

... sense for reading data will never be modified. Trying to use that to read tables that would be written to means that you will in practice read something that gets rolled back. It's not just that you are reading data that's a few seconds old, but you ....................................................
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Tools for JPEG optimization? [closed]

... tools I could find, including MozJPEG and jpegoptim that optimize Huffman tables, progressive scans, and (optionally) remove invisible metadata. If you don't have a Mac, I also have a basic web interface that works on any platform. ...
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Working copy XXX locked and cleanup failed in SVN

...deleting a record in the SQLite ".svn\wc" file lock record in the WC_LOCK table. I opened the "WC" file with SQLite editor and executed delete from WC_LOCK Following eakkas's comment, you might need to delete all the entries from WORK_QUEUE table as well. ...