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MySQL Error 1093 - Can't specify target table for update in FROM clause
...n case certain operations are carried out, merging cannot happen. E.g. provide the derived dummy table with a LIMIT (to inifity) and the error will never occur. That's pretty hackish though and there is still the risk that future versions of MySQL will support merging queries with LIMIT after all.
...
Foreign Key to multiple tables
...on your needs.
You could simply create two columns in Ticket, OwnedByUserId and OwnedByGroupId, and have nullable Foreign Keys to each table.
You could create M:M reference tables enabling both ticket:user and ticket:group relationships. Perhaps in future you will want to allow a single ticket to ...
Rails 3: Get Random Record
... on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select max(id) from my_table) + 1
)
order by id
limit 1;
share
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improve this answer
...
Is it possible to use raw SQL within a Spring Repository
...me = "USER_INFO_TEST")
public class UserInfoTest {
private int id;
private String name;
private String rollNo;
public UserInfoTest() {
}
public UserInfoTest(int id, String name) {
this.id = id;
this.name = name;
}
...
Switching the order of block elements with CSS [duplicate]
...ly need to support a single modern browser: Mobile Safari.
See: http://jsfiddle.net/thirtydot/hLUHL/
You can remove the -moz- prefixed properties if you like, I just left them in for future readers.
#blockContainer {
display: -webkit-box;
display: -moz-box;
disp...
What is the difference between shallow copy, deepcopy and normal assignment operation?
... 6]
c = [a, b]
Using normal assignment operatings to copy:
d = c
print id(c) == id(d) # True - d is the same object as c
print id(c[0]) == id(d[0]) # True - d[0] is the same object as c[0]
Using a shallow copy:
d = copy.copy(c)
print id(c) == id(d) # False - d is now a n...
PostgreSQL delete with inner join
...
DELETE
FROM m_productprice B
USING m_product C
WHERE B.m_product_id = C.m_product_id AND
C.upc = '7094' AND
B.m_pricelist_version_id='1000020';
or
DELETE
FROM m_productprice
WHERE m_pricelist_version_id='1000020' AND
m_product_id IN (SELECT m_product...
“ArrayAdapter requires the resource ID to be a TextView” xml problems
...
The ArrayAdapter requires the resource ID to be a TextView XML exception means you don't supply what the ArrayAdapter expects. When you use this constructor:
new ArrayAdapter<String>(this, R.layout.a_layout_file, this.file)
R.Layout.a_layout_file must be ...
How to make layout with View fill the remaining space?
...veLayout.
I am giving my layout for clarity:
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
>
<Button
android:layout_width = "80dp"
android:layout_weight = "0"
and...
How to extract the decision rules from scikit-learn decision-tree?
...ormat(indent, tree_.value[node])
recurse(0, 1)
This prints out a valid Python function. Here's an example output for a tree that is trying to return its input, a number between 0 and 10.
def tree(f0):
if f0 <= 6.0:
if f0 <= 1.5:
return [[ 0.]]
else: # if f0 > 1.5
...