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When is it right for a constructor to throw an exception?
...nstructor's job is to bring the object into a usable state. There are basically two schools of thought on this.
One group favors two-stage construction. The constructor merely brings the object into a sleeper state in which it refuses to do any work. There's an additional function that does the act...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...several mysql clients (navicat, sequel pro).
It does not mean anything AT ALL! I ran a test, all above clients or even the command-line client seems to ignore this.
But, display width is most important if you are using ZEROFILL option, for example your table has following 2 columns:
A tinyint(2) ...
Rails migrations: self.up and self.down versus change
... For example, in your case what is the reverse operation of add_column to call when you rollback? Of course it's remove_column. What is the inverse of create_table? It's drop_table. So in these cases rails know how to rollback and define a down method is superfluous (you can see in the documentation...
How to hide databases that I am not allowed to access
... I connect to my Heroku - Postgresql database via pgAdmin3 , It lists all the tables (about 2600). Every time I open the pgAdmin3 I have to find my own database.
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Why are nested weights bad for performance? Alternatives?
...with non-zero weights, then the number of measurements
increase exponentially.
It's better to use RelativeLayouts and adjust your view according to the places of other views without using specific dpi values.
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Right query to get the current number of connections in a PostgreSQL DB
...ence.
Both queries are based on exactly the same data, so they will be equally accurate.
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What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
...bar', so loop runs once and
done # prints nothing (actually "")
var="foo bar"
for i in "${var}bar"; do # Expands to 'for i in "foo barbar"; do...'
echo $i # so runs the loop once
done
# foo barbar
Note that "${var}bar" in the second example above could also ...
Include headers when using SELECT INTO OUTFILE?
...yourself. Something like:
SELECT 'ColName1', 'ColName2', 'ColName3'
UNION ALL
SELECT ColName1, ColName2, ColName3
FROM YourTable
INTO OUTFILE '/path/outfile'
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In C#, how do I calculate someone's age based on a DateTime type birthday?
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This answer does not work with all locales and all ages. Several countries have skipped dates after the birth of current living people, including Russia (1918), Greece (1924) and Turkey (1926).
– Lars D
Nov 9 '09 at 2...
How to create a database from shell command?
...for something like createdb in PostgreSQL or any other solution that would allow me to create database with a help of a shell command. Any hints?
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