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Paging with Oracle
...T * FROM
(
SELECT a.*, rownum r__
FROM
(
SELECT * FROM ORDERS WHERE CustomerID LIKE 'A%'
ORDER BY OrderDate DESC, ShippingDate DESC
) a
WHERE rownum < ((pageNumber * pageSize) + 1 )
)
WHERE r__ >= (((pageNumber-1) * pageSize) + 1)
...
Entity Attribute Value Database vs. strict Relational Model Ecommerce
... information.
CREATE OR REPLACE VIEW sales_flat_addresses AS
SELECT sales_order_entity.parent_id AS order_id,
sales_order_entity.entity_id,
CONCAT(CONCAT(UCASE(MID(sales_order_entity_varchar.value,1,1)),MID(sales_order_entity_varchar.value,2)), "Address") as type,
GROUP_CONC...
What is the difference between List (of T) and Collection(of T)?
...
In C#, there are three concepts for representing a bag of objects. In order of increasing features, they are:
Enumerable - unordered, unmodifiable
Collection - can add/remove items
List - allows items to have an order (accessing and removing by index)
Enumerable has no order. You cannot add...
How to maintain a Unique List in Java?
... low) if iteration performance is important.
When iterating a HashSet the order of the yielded elements is undefined.
LinkedHashSet
Hash table and linked list implementation of the Set interface, with predictable iteration order. This implementation differs from HashSet in that it maintains a doub...
In which order should floats be added to get the most precise result?
...
Your instinct is basically right, sorting in ascending order (of magnitude) usually improves things somewhat. Consider the case where we're adding single-precision (32 bit) floats, and there are 1 billion values equal to 1 / (1 billion), and one value equal to 1. If the 1 comes f...
The order of keys in dictionaries
...
You could use OrderedDict (requires Python 2.7) or higher.
Also, note that OrderedDict({'a': 1, 'b':2, 'c':3}) won't work since the dict you create with {...} has already forgotten the order of the elements. Instead, you want to use Order...
PostgreSQL Crosstab Query
...ELECT *
FROM crosstab(
'SELECT section, status, ct
FROM tbl
ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here
) AS ct ("Section" text, "Active" int, "Inactive" int);
Returns:
Section | Active | Inactive
---------+--------+----------
A | 1 | 2
B | ...
Constructor initialization-list evaluation order
...hat takes some arguments. I had assumed that they were constructed in the order listed, but in one case it appears they were being constructed in reverse resulting in an abort. When I reversed the arguments the program stopped aborting. This is an example of the syntax I'm using. The thing is, a_...
How to randomly select rows in SQL?
...
SELECT TOP 5 Id, Name FROM customerNames
ORDER BY NEWID()
That said, everybody seems to come to this page for the more general answer to your question:
Selecting a random row in SQL
Select a random row with MySQL:
SELECT column FROM table
ORDER BY RAND()
LIMIT ...
How to sort a list in Scala by two fields?
...
@SachinK: you have to create your own Ordering for Row class and use it with sorted method like this: rows.sorted(customOrdering). You could also use custom Ordering for Tuple2 like this: rows.sortBy(r => (r.lastName, r.firstName))( Ordering.Tuple2(Ordering.St...