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how to listen to N channels? (dynamic select statement)
to start an endless loop of executing two goroutines, I can use the code below:
5 Answers
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Argparse optional positional arguments?
I have a script which is meant to be used like this:
usage: installer.py dir [-h] [-v]
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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
Is there an easy way to INSERT a row when it does not exist, or to UPDATE if it exists, using one MySQL query?
2 Answer...
Adding IN clause List to a JPA Query
I have built a NamedQuery that looks like this:
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What's the valid way to include an image with no src?
I have an image that I will dynamically populate with a src later with javascript but for ease I want the image tag to exist at pageload but just not display anything. I know <img src='' /> is invalid so what's the best way to do this?
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jQuery - get a list of values of an attribute from elements of a class
I have a class .object which has an attribute called level . I want to get a list of all the different values of level on the page so I can select the highest one.
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Is there any haskell function to concatenate list with separator?
Is there a function to concatenate elements of a list with a separator?
For example:
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How to do a less than or equal to filter in Django queryset?
I am attempting to filter users by a custom field in each users profile called profile. This field is called level and is an integer between 0-3.
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List distinct values in a vector in R
How can I list the distinct values in a vector where the values are replicative? I mean, similarly to the following SQL statement:
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How to check for Is not Null And Is not Empty string in SQL server?
How can we check in a SQL Server WHERE condition whether the column is not null and not the empty string ( '' )?
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