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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...of PostgreSQL
In old versions of PostgreSQL (prior to 8.x?) you had to do all the dirty work. The following sequence of commands should do the trick:
ALTER TABLE test1 ADD COLUMN id INTEGER;
CREATE SEQUENCE test_id_seq OWNED BY test1.id;
ALTER TABLE test ALTER COLUMN id SET DEFAULT nextval('...
MIN and MAX in C
Where are MIN and MAX defined in C, if at all?
14 Answers
14
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How can I get a view's current width and height when using autolayout constraints?
...our existing constraints, the answer is not to inspect the constraints manually, since that would require you to re-implement the entire constraint-solving logic of the auto layout system in order to interpret those constraints. Instead, what you should do is just ask auto layout to update that layo...
“You are on a branch yet to be born” when adding git submodule
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I've verified all of these things. When I check out the desired repo to another directory, it has many files, and a master branch. The repo I am trying to add this one to as a submodule is on the master branch, has no obvious problems (sta...
When would you use .git/info/exclude instead of .gitignore to exclude files?
...gnore rules, unlike .git/info/exclude.
So, .gitignore is available across all clones of the repository. Therefore, in large teams all people are ignoring the same kind of files Example *.db, *.log.
And you can have more specific ignore rules because of multiple .gitignore.
.git/info/exclude is av...
Declaring variables inside or outside of a loop
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The scope of local variables should always be the smallest possible.
In your example I presume str is not used outside of the while loop, otherwise you would not be asking the question, because declaring it inside the while loop would not be an option, since it would not comp...
Is there YAML syntax for sharing part of a list or map?
... what you want. It uses a special << mapping key to indicate merges, allowing an alias to a mapping (or a sequence of such aliases) to be used as an initializer to merge into a single mapping. Additionally, you can still explicitly override values, or add more that weren't present in the merge...
Comparing boxed Long values 127 and 128
... If the data type of above variable is primitive (long) then code work for all values.
Java caches Integer objects instances from the range -128 to 127. That said:
If you set to N Long variables the value 127 (cached), the same object instance will be pointed by all references. (N variables, 1 i...
Why do we need C Unions?
...ad of u.f
– Amit Singh Tomar
Sep 8 '11 at 8:17
1
Does the example which suppose to convert float ...
How to update a pull request from forked repo?
...to that forked repo. I then opened a pull request. The pull request listed all the changes I wanted.
5 Answers
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