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Find difference between timestamps in seconds in PostgreSQL
I have a table in PostgreSQL 8.3 with 2 timestamp columns. I would like to get the difference between these timestamps in seconds. Could you please help me how to get this done?
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Java system properties and environment variables
What's the difference between system properties System.getProperties() and environment variables System.getenv() in a JVM?
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MySQL: Selecting multiple fields into multiple variables in a stored procedure
Can I SELECT multiple columns into multiple variables within the same select query in MySQL?
3 Answers
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How to track child process using strace?
I used strace to attach to a process briefly. The process created 90 threads. When I found the offending thread, I had to tediously search for the parent thread, then the grandparent thread, and so on all the way to the root process.
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Scala: what is the best way to append an element to an Array?
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Html.BeginForm and adding properties
How would I go about adding enctype="multipart/form-data" to a form that is generated by using <% Html.BeginForm(); %> ?
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Getting the encoding of a Postgres database
I have a database, and I need to know the default encoding for the database. I want to get it from the command line.
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R object identification
I am often ending up with a function producing output for which I don't understand the output data type. I'm expecting a list and it ends up being a list of lists or a data frame or something else. What's a good method or workflow for figuring out the output data type when first using a function?
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How do I get the MIN() of two fields in Postgres?
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Is there a way to use two CSS3 box shadows on one element?
I'm trying to replicate a button style in a Photoshop mock-up that has two shadows on it. The first shadow is an inner lighter box shadow (2px), and the second is a drop shadow outside the button (5px) itself.
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