database-partitioning

I am trying to grasp the different concepts of Database Partitioning and this is what I understood of it: Horizontal Partitioning/Sharding : Splitting a table into different table that will contain a subset of the rows that were in the initial table (an example that I have seen a lot if splitting a Users table by Continent, like a sub table for North America, another one for Europe, etc...). Each partition being in a different physical location (understand 'machine'). As I understood it, Horizontal Partitioning and Sharding are the exact same thing(?). Vertical Partitioning : From what I

I have a problem with a query. Here is the query. SELECT UserID, MAX(UserName) as UserName, MAX(TransactionTime) as TransactionTime, MAX(LastAction) as LastAction FROM UserActivities WHERE OrganizationID = 26465 GROUP BY UserID There are so many records for particular user at different TransactionTime. I want to take LastAction along with other records. How can I do it? Is SQL partition will work here? A ranking function is probably what you are looking for: SELECT * FROM ( SELECT UserID, UserName, LastAction, row_number() over(partition by UserId order by TransactionTime desc) RowNo FROM

I have a table that is partitioned by TRANSACTION_DATE_TIME. Table has a column: ID. I want to create a unique index for ID on partition scheme as: CREATE UNIQUE NONCLUSTERED INDEX [IX_ID_ON_PS_DATETIME] ON [CRD].[TRANSACTION] ( [ID] ASC ) ON [PS_DATETIME_WEEKLY]([TRANSACTION_DATE_TIME]) but SQL says "Partition column for a unique index must be a subset of index key". I really don't need TRANSACTION_DATE_TIME column in this index. How can I create the index without using TRANSACTION_DATE_TIME column? Or you create NON -partitioned index, or you HAVE to include the partitioning key into

Can you provide a very simple SQL example of how to create a "count" or "order" field that would auto-increment, but restart after every change in a different field? In the table below, the "Order" field would restart at "1" every time there was a change in the "Meal" field. Thanks. Meal Time Order Lunch 10:30 1 Lunch 11:00 2 Lunch 11:15 3 Dinner 4:30 1 Dinner 4:45 2 Dinner 5:00 3 Dinner 5:30 4 Instead of storing Order in the table, consider adding it to a view. You can select from the view instead of the table when you need it. The view could use row_number() to calculate the order, like:

I am trying to recap on my sql skill, now I am trying to run a simple query on northwinddb to show me the top customer for each year, but as soon as I use the TOP function only 1 record gets display no matter on what I partition by, This is my T-SQL code SELECT DISTINCT TOP 1 C.CompanyName , YEAR(O.OrderDate) AS Year , SUM(Quantity) OVER(PARTITION BY C.CompanyName, YEAR(O.OrderDate)) AS Total FROM Customers C JOIN Orders O ON C.CustomerID = O.CustomerID JOIN [Order Details] OD ON O.OrderID = OD.OrderID You can do this bit more compactly in SQL Server 2008 as follows: select top (1) with ties C