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How to determine if a record is just created or updated in after_save
The #new_record? function determines if a record has been saved. But it is always false in the after_save hook. Is there a way to determine whether the record is a newly created record or an old one from update?
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How to display line numbers in 'less' (GNU)
What is the command to make less display line numbers in the left column?
6 Answers
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Error: The processing instruction target matching “[xX][mM][lL]” is not allowed
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7 Answers
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PostgreSQL - fetch the row which has the Max value for a column
I'm dealing with a Postgres table (called "lives") that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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Prevent text selection after double click
I'm handling the dblclick event on a span in my web app. A side-effect is that the double click selects text on the page. How can I prevent this selection from happening?
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history.replaceState() example?
Can any one give a working example for history.replaceState? This is what w3.org says:
8 Answers
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Deleting Row in SQLite in Android
This might be a dumb question, but I'm new to SQLite and I can't seem to figure this out. I have 1 table that has columns KEY_ROWID , KEY_NAME , KAY_LATITUDE , and KEY_LONGITUDE . I want the user to be able to select one and delete it; Can anyone give me a direction to start in? My question i...
Java Enum definition
I thought I understood Java generics pretty well, but then I came across the following in java.lang.Enum:
7 Answers
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How do I find the width & height of a terminal window?
As a simple example, I want to write a CLI script which can print = across the entire width of the terminal window.
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Docker - how can I copy a file from an image to a host?
My question is related to this question on copying files from containers to hosts; I have a Dockerfile that fetches dependencies, compiles a build artifact from source, and runs an executable. I also want to copy the build artifact (in my case it's a .zip produced by sbt dist in '../target/`, ...