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How do I find duplicate values in a table in Oracle?
...= oed.deptid )
group by oed.empid having count(oed.empid) > 1 order by count(oed.empid);
and if such table has primary key then use primary key instead of rowid, e.g id is pk then
select oed.empid, count(oed.empid)
from emp_dept oed
where exists ( select *
from emp...
What are major differences between C# and Java?
... visibility in Java which takes account of namespace (and inheritance)
The order of initialization in Java and C# is subtly different (C# executes variable initializers before the chained call to the base type's constructor)
Java doesn't have properties as part of the language; they're a convention ...
Object-orientation in C
...the derived class. Multiple inheritance is much harder - in that case, in order to case between base classes other than the first, you need to manually adjust your pointers based on the proper offsets, which is really tricky and error-prone.
Another (tricky) thing you can do is change the dynamic ...
Dump a mysql database to a plaintext (CSV) backup from the command line
...
In MySQL itself, you can specify CSV output like:
SELECT order_id,product_name,qty
FROM orders
INTO OUTFILE '/tmp/orders.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n'
From http://www.tech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-fil...
PHP filesize MB/KB conversion [duplicate]
...verage ~40% slower but for 1024 and above I get consistent averages on the order of 0.1%. Interesting!
– Alix Axel
May 25 '13 at 3:55
...
How do I apply the for-each loop to every character in a String?
...
In Java 8 we can solve it as:
String str = "xyz";
str.chars().forEachOrdered(i -> System.out.print((char)i));
The method chars() returns an IntStream as mentioned in doc:
Returns a stream of int zero-extending the char values from this
sequence. Any char which maps to a surrogat...
How can I pair socks from a pile efficiently?
...was doing a naive search — picking one sock and "iterating" the pile in order to find its pair. This requires iterating over n/2 * n/4 = n 2 /8 socks on average.
...
Using GPU from a docker container?
...he date.
These 2 numbers are called major and minor numbers (wrote in that order) and design a device.
We will just use the major numbers for convenience.
Why do we activated lxc driver?
To use the lxc conf option that allow us to permit our container to access those devices.
The option is : (i rec...
Why are joins bad when considering scalability?
...spreading out, or paring down the repeated work to the bare essentials, in order to minimize resource use per work unit. To scale well, you don't do anything you don't need to in volume, and the things you actually do you make sure are done as efficiently as possible.
In that context, of course join...
How to do paging in AngularJS?
...xpression that could be validly used in an ng-repeat, including filtering, ordering etc.
Works across controllers - the pagination-controls directive does not need to know anything about the context in which the paginate directive is called.
Demo : http://plnkr.co/edit/Wtkv71LIqUR4OhzhgpqL?p=previe...