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Disable all table constraints in Oracle
...nk about putting constraint_type in the WHERE clause.
BEGIN
FOR c IN
(SELECT c.owner, c.table_name, c.constraint_name
FROM user_constraints c, user_tables t
WHERE c.table_name = t.table_name
AND c.status = 'ENABLED'
AND NOT (t.iot_type IS NOT NULL AND c.constraint_type = 'P')
ORD...
JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
...
Regular expression to allow spaces between words
...
tl;dr
Just add a space in your character class.
^[a-zA-Z0-9_ ]*$
Now, if you want to be strict...
The above isn't exactly correct. Due to the fact that * means zero or more, it would match all of the following cases that one would not usually mea...
How do I check how many options there are in a dropdown menu?
...
var length = $('#mySelectList').children('option').length;
or
var length = $('#mySelectList > option').length;
This assumes your <select> list has an ID of mySelectList.
http://api.jquery.com/length/
http://api.jquery.com/childr...
Select datatype of the field in postgres
...tion_schema (8.4 docs referenced here, but this is not a new feature):
=# select column_name, data_type from information_schema.columns
-# where table_name = 'config';
column_name | data_type
--------------------+-----------
id | integer
default_printer_id | integer
mast...
Select where count of one field is greater than one
...clause, for aggregate result comparison.
Taking the query at face value:
SELECT *
FROM db.table
HAVING COUNT(someField) > 1
Ideally, there should be a GROUP BY defined for proper valuation in the HAVING clause, but MySQL does allow hidden columns from the GROUP BY...
Is this in preparati...
How can I remove the first line of a text file using bash/sed script?
... of magnitude. I'm testing it on a file of 500,000K lines (no more than 50 chars per line). However, I then realized I was using the FreeBSD version of tail (which comes with OS X by default). When I switched to GNU tail, the tail call was 10 times faster than the sed call (and the GNU sed call, too...
What is the worst real-world macros/pre-processor abuse you've ever come across?
...efine static
#define void int
#define main(x) main()
struct F{void println(char* s){std::cout << s << std::endl;}};
struct S{F out;};
public static void main(String[] args) {
System.out.println("Hello World!");
}
Challenge: Can anyone do it with fewer defines and structs? ;-)
...
Get records with max value for each group of grouped SQL results
...
There's a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. T...
How does the Comma Operator work
...’t work since then the compiler just sees the comma operator between two char[], which cannot be overloaded. The code intentionally first calls the operator= and then subsequently operator, for each remaining element.
– Konrad Rudolph
Oct 9 '11 at 11:04
...