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Does Python have an ordered set?
...list.
OrderedSet([1, 2, 3])
This is a MutableSet, so the signature for .union doesn't match that of set, but since it includes __or__ something similar can easily be added:
@staticmethod
def union(*sets):
union = OrderedSet()
union.union(*sets)
return union
def union(self, *sets):
...
JOIN two SELECT statement results
...
Use UNION:
SELECT ks, COUNT(*) AS '# Tasks' FROM Table GROUP BY ks
UNION
SELECT ks, COUNT(*) AS '# Late' FROM Table WHERE Age > Palt GROUP BY ks
Or UNION ALL if you want duplicates:
SELECT ks, COUNT(*) AS '# Tasks' FROM Ta...
How to combine two or more querysets in a Django view?
...
Here | is the set union operator, not bitwise OR.
– e100
Mar 26 '15 at 18:53
...
How do you use the “WITH” clause in MySQL?
...to write queries like this:
WITH RECURSIVE my_cte AS
(
SELECT 1 AS n
UNION ALL
SELECT 1+n FROM my_cte WHERE n<10
)
SELECT * FROM my_cte;
+------+
| n |
+------+
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
| 6 |
| 7 |
| 8 |
| 9 |
| 10 |
+------+
10 rows in set (0,00 sec)
...
Check if a class has a member function of a given signature
...her down
Check for member x in a given class. Could be var, func, class, union, or enum:
CREATE_MEMBER_CHECK(x);
bool has_x = has_member_x<class_to_check_for_x>::value;
Check for member function void x():
//Func signature MUST have T as template variable here... simpler this way :\
CREAT...
What's the difference between array_merge and array + array?
...
The difference is:
The + operator takes the union of the two arrays, whereas the array_merge function takes the union BUT the duplicate keys are overwritten.
share
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i...
How to select multiple rows filled with constants?
...
SELECT 1, 2, 3
UNION ALL SELECT 4, 5, 6
UNION ALL SELECT 7, 8, 9
share
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improve this answer
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follow
...
How to join two sets in one line without using “|”
...are assigned sets. Without using the join operator | , how can I find the union of the two sets? This, for example, finds the intersection:
...
Number of rows affected by an UPDATE in PL/SQL
...rowcount);
insert into client
select 1, 'void' from dual
union all select 4, 'void' from dual
union all select 1, 'void' from dual
union all select 6, 'void' from dual
union all select 10, 'void' from dual;
dbms_output.put_line('Number of lines affected by previous DML op...
How to get first and last day of previous month (with timestamp) in SQL Server
...st month' AS Title, CONVERT(VARCHAR, @FirstDayOfLastMonth , 120) AS [ODBC]
UNION
SELECT
'Last day of last month' AS Title, CONVERT(VARCHAR, @LastDayOfLastMonth , 120) AS [ODBC]
Run the above code to produce the following output:
Note: Bear in mind that today's date for me is 12th Septemb...