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How do I modify a MySQL column to allow NULL?
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This did not work for me! The column did not change. Maybe because I had a constraint to another table where the column was used (when not null).
– Rocologo
Dec 18 '16 at 10:09
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Alter Table Add Column Syntax
I'm trying to programmatically add an identity column to a table Employees. Not sure what I'm doing wrong with my syntax.
4...
Difference between this and self in self-type annotations?
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All three forms are valid, and have the effect that B is assumed as the type of this in class A.
The first two variants
trait A { self: B => ... }
trait A { foo: B => ... }
introduce self (respectively, foo) as an alias for this in trait...
Differences between utf8 and latin1
...AR and decode/encode in the business tier yourself, but this is hacky. Consider asking a new question, maybe there are better ways.
– BalusC
Jun 12 '12 at 18:57
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Event handling for iOS - how hitTest:withEvent: and pointInside:withEvent: are related?
...ile most apple documents are very well written, I think ' Event Handling Guide for iOS ' is an exception. It's hard for me to clearly understand what's been described there.
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differences between 2 JUnit Assert classes
...it.framework.Assert and org.junit.Assert. It is, however, probably a good idea to stick to the org.junit.Assert class since it is newer , slightly rewritten and probably meant as a replacement.
– Glenn Bech
Nov 30 '15 at 9:51
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How do I convert an interval into a number of hours with postgres?
... SELECT EXTRACT(epoch FROM my_interval/3600) (interval has native 'divide integer' support, result is interval, and extract result is integer, not float). So. Autocast/Floor done.
– Offenso
Aug 12 '15 at 13:24
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How can I define a composite primary key in SQL?
...te primary key. It is defined as follows:
CREATE TABLE voting (
QuestionID NUMERIC,
MemberID NUMERIC,
PRIMARY KEY (QuestionID, MemberID)
);
The pair (QuestionID,MemberID) must then be unique for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHER...
In Maven 2, how do I know from which dependency comes a transitive dependency?
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To add to @David Crow, here's a dependency:tree example from the Maven site:
mvn dependency:tree -Dincludes=velocity:velocity
might output
[INFO] [dependency:tree]
[INFO] org.apache.maven.plugins:maven-dependency-plugin:maven-plugin:2....
how to make svn diff show only non-whitespace line changes between two revisions
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Because EOL may be considered whitespace as well, adding -x --ignore-eol-style might be necessary if EOL style is different between revisions.
– nedim
Apr 27 '15 at 14:09
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