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MySQL Error 1093 - Can't specify target table for update in FROM clause
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Update: This answer covers the general error classification. For a more specific answer about how to best handle the OP's exact query, please see other answers to this question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:
http:...
Deleting all records in a database table
...n_id = 5 AND (category = 'Something' OR category = 'Else')"
See here for more information.
The records are deleted without loading them first which makes it very fast but will break functionality like counter cache that depends on rails code to be executed upon deletion.
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Why malloc+memset is slower than calloc?
...) will first try to get 16 bytes out of one of its pools, and then ask for more memory from the kernel when the pool runs dry. However, since the program you're asking about is allocating for a large amount of memory at once, malloc() and calloc() will just ask for that memory directly from the ker...
Do sessions really violate RESTfulness?
... and password on the client and send it with every request. You don't need more to do this than HTTP basic auth and an encrypted connection:
Figure 1. - Stateless authentication by trusted clients
You probably need an in-memory auth cache on server side to make things faster, since you have to...
What is the { get; set; } syntax in C#?
..., can you explain what will happen with this code? It could benefit from a more thorough explanation.
– TylerH
Nov 17 '14 at 18:53
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How to find a text inside SQL Server procedures / triggers?
...red procedure names that contain text like 'User' inside stored procedure. More info
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How to create a density plot in matplotlib?
...v R flame wars or anything, but I am loving the way R works with data much more succinctly that python and other languages. I'm sure python has lots of good points over R (I'm not a Python user so I'm so totally uniformed to possibly comment) and can be used for lots more work than analysing data, b...
Extending the User model with custom fields in Django
...User model is not always appropriate. For instance, on some sites it makes more sense to use an email address as your identification token instead of a username.
[Ed: Two warnings and a notification follow, mentioning that this is pretty drastic.]
I would definitely stay away from changing the actu...
How to check if a string in Python is in ASCII?
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Inefficient or not, the more pythonic method is the try/except.
– Jeremy Cantrell
Oct 14 '08 at 14:38
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“document.getElementByClass is not a function”
... that makes sense. Is the a function for selecting all classnames that is more browser compliant? Or is it possible to select a range for the array nodes? (ie. 0-100)?
– user547794
Sep 20 '11 at 5:27
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