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MySQL ON vs USING?
In a MySQL JOIN , what is the difference between ON and USING() ? As far as I can tell, USING() is just more convenient syntax, whereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USI...
SQL Server 2008: How to query all databases sizes?
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@Derek Smith - size column is in pages. The size of one page is 8kB, hence the formula SizeInMb = PagesCount * 8 / 1024. I always believed 1MB = 1024kB. I don't think that even Microsoft has enough power to change this :).
– Alex Aza...
Disable a Maven plugin defined in a parent POM
I am using a parent POM that defines a plugin that I do not want to be run in a child POM. How can I disable the plugin in the child pom completely?
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Python assigning multiple variables to same value? list behavior
I tried to use multiple assignment as show below to initialize variables, but I got confused by the behavior, I expect to reassign the values list separately, I mean b[0] and c[0] equal 0 as before.
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Schema for a multilanguage database
I'm developing a multilanguage software. As far as the application code goes, localizability is not an issue. We can use language specific resources and have all kinds of tools that work well with them.
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Removing App ID from Developer Connection
...m portal area? I mistakenly added a couple of app id's under the wrong login and would like to remove them, but I am not seeing a way to do so.
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Rails auto-assigning id that already exists
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Rails is probably using the built-in PostgreSQL sequence. The idea of a sequence is that it is only used once.
The simplest solution is to set the sequence for your company.id column to the highest value in the table with a query like this:
SE...
Objective-C: difference between id and void *
... barriers for references of type id, but not for type void *. When declaring structures, this can be a critical difference. Declaring iVars like void *_superPrivateDoNotTouch; will cause premature reaping of objects if _superPrivateDoNotTouch is actually an object. Don't do that.
attempting to ...
What is SYSNAME data type in SQL Server?
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sysname is a built in datatype limited to 128 Unicode characters that, IIRC, is used primarily to store object names when creating scripts. Its value cannot be NULL
It is basically the same as using nvarchar(128) NOT NULL
EDIT
As mentioned b...
How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
I have a table with existing data. Is there a way to add a primary key without deleting and re-creating the table?
4 Answer...