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How do I check if a column is empty or null in MySQL?
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This will select all rows where some_col is NULL or '' (empty string)
SELECT * FROM table WHERE some_col IS NULL OR some_col = '';
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Sublime Text 3, convert spaces to tabs
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yes, I know. My desire is to make this automatically ... any idea?
– chris
Mar 20 '14 at 14:02
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What does it mean when an HTTP request returns status code 0?
What does it mean when JavaScript network calls such as fetch or XMLHttpRequest, or any other type of HTTP network request, fail with an HTTP status code of 0?
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What is the difference between the Eclipse Package Explorer and the Eclipse Project Explorer?
It seems to me these two views are virtually identical, especially since Galileo. Is this true, or am I missing out on some features of one or the other?
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What is the optimal length for user password salt? [closed]
Any salt at all will obviously help when salting and hashing a user's password. Are there any best practices for how long the salt should be? I'll be storing the salt in my user table, so I would like the best tradeoff between storage size and security. Is a random 10 character salt enough? Or ...
Generate random int value from 3 to 6
...details check this: https://www.techonthenet.com/sql_server/functions/rand.php
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What algorithms compute directions from point A to point B on a map?
...oughly half the work (2*pi*(r/2)^2 vs pi*r^2).
To avoid exploring the back-alleys of every city between your source and destination, you can have several layers of map data: A 'highways' layer that contains only highways, a 'secondary' layer that contains only secondary streets, and so forth. Then, ...
How to call shell commands from Ruby
How do I call shell commands from inside of a Ruby program? How do I then get output from these commands back into Ruby?
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In Windows cmd, how do I prompt for user input and use the result in another command?
...o accept user input and then use the results of that input as part of the call to additional commands.
12 Answers
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How to discard local changes in an SVN checkout?
...er changes are not required : """Rest of the changes I made, were for basically debugging, and are no longer required.""" :)
– Cédric Julien
Feb 27 '12 at 10:54
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