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Selecting data from two different servers in SQL Server
How can I select data in the same query from two different databases that are on two different servers in SQL Server?
15 An...
Add list to set?
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With respect to sets, the | operator implements the set union operation. Both the |= operator and set.update() method apply that operation in-place and are effectively synonymous. So, set_a |= set_b could be considered syntactic sugar for both set_a.update(set_b) and set_a = set_a...
How do I get the size of a java.sql.ResultSet?
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Do a SELECT COUNT(*) FROM ... query instead.
OR
int size =0;
if (rs != null)
{
rs.last(); // moves cursor to the last row
size = rs.getRow(); // get row id
}
In either of the case, you won't have to loop over the enti...
Extract a dplyr tbl column as a vector
...2 3.62 3.54 4.11
A nice way to do this in v0.2 of dplyr:
iris2 %>% select(Species) %>% collect %>% .[[5]]
Or if you prefer:
iris2 %>% select(Species) %>% collect %>% .[["Species"]]
Or if your table isn't too big, simply...
iris2 %>% collect %>% .[["Species"]]
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Inserting multiple rows in mysql
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it's also possible to use INSERT INTO Table SELECT 1, '14/05/2012', 3 UNION SELECT 2, '05/14/2012', 3. of course, this will only be better of the inserted values are coming from different tables.
– Zohar Peled
Jun 1 '15 at 9:18
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MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
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Rewrite the query into this
SELECT st1.*, st2.relevant_field FROM sometable st1
INNER JOIN sometable st2 ON (st1.relevant_field = st2.relevant_field)
GROUP BY st1.id /* list a unique sometable field here*/
HAVING COUNT(*) > 1
I think st2.relevant_...
Possible to do a MySQL foreign key to one of two possible tables?
...ecific type of filter is easy if you know which type you want to join to:
SELECT * FROM Products
INNER JOIN FiltersType2 USING (product_id)
If you want the filter type to be dynamic, you must write application code to construct the SQL query. SQL requires that the table be specified and fixed at ...
How to push both value and key into PHP array
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You can use the union operator (+) to combine arrays and keep the keys of the added array. For example:
<?php
$arr1 = array('foo' => 'bar');
$arr2 = array('baz' => 'bof');
$arr3 = $arr1 + $arr2;
print_r($arr3);
// prints:
// arr...
How to create a SQL Server function to “join” multiple rows from a subquery into a single delimited
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If you're using SQL Server 2005, you could use the FOR XML PATH command.
SELECT [VehicleID]
, [Name]
, (STUFF((SELECT CAST(', ' + [City] AS VARCHAR(MAX))
FROM [Location]
WHERE (VehicleID = Vehicle.VehicleID)
FOR XML PATH ('')), 1, 2, '')) AS Locations
FROM [...
Append values to a set in Python
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You can also use the | operator to concatenate two sets (union in set theory):
>>> my_set = {1}
>>> my_set = my_set | {2}
>>> my_set
{1, 2}
Or a shorter form using |=:
>>> my_set = {1}
>>> my_set |= {2}
>>> my_set
{1, 2}
N...