Unlike the PIVOT, newly added documents can be displayed without altering the script. Similar to the PIVOT and the Cursor, newly added policies are able to be retrieved in the XML version of the script without altering the original script. The XML version of the script addresses this limitation by using a combination of XML Path, dynamic T-SQL and some built-in functions (i.e. The XML solution to transposing rows into columns is basically an optimal version of the PIVOT in that it addresses the dynamic column limitation. This is because the Cursor generates a separate query for each FETCH NEXT operation.Īnother solution of transposing rows into columns is by using XML. The major limitation of transposing rows into columns using CURSOR is a disadvantage that is linked to using cursors in general – they come at significant performance cost. Unlike the PIVOT, the cursor excels in this area as it is able to expand to include newly added document, without altering the script. Similar to the PIVOT, the cursor has the dynamic capability to append more rows as your dataset expands to include more policy numbers. Anyway, Cursors present us with another option to transpose rows into columns.
Sqlpro studio transpose professional#
Although the general consensus in the professional community is to stay away from SQL Server Cursors, there are still instances whereby the use of cursors is recommended. I'd like to point out few more solutions to transposing columns and rows in SQL. The above can be combined into a dynamic sql batch to handle any table.You can also build up the list of distinct colors (or values for one column) using FOR XML.Given a table name, you can determine all the column names from sys.columns or FOR XML trickery using local-name().MS SQL Server 2012 Schema Setup: create table tbl (Ĭolor varchar(10), Paul int, John int, Tim int, Eric int) As you can see in the query below, the labels are all listed in their entirely in both the UNPIVOT and the (re)PIVOT operations. This normally requires you to know ALL the column AND row labels beforehand.
Sqlpro studio transpose plus#
The plus of the dynamic version is if you have a changing list of colors and/or names this will generate the list at run-time.Īll three queries will produce the same result: | NAME | RED | GREEN | BLUE | This is then added to a query string to be executed. The dynamic version queries both yourtable and then the sys.columns table to generate the list of items to UNPIVOT and PIVOT. Where C.object_id = object_id('yourtable') and Select = stuff((select ','+quotename(C.name) If you have an unknown number of columns ( Paul, John, Tim, Eric in your example) and then an unknown number of colors to transform you can use dynamic sql to generate the list to UNPIVOT and then PIVOT: DECLARE AS AS as NVARCHAR(MAX) It takes the list of columns and turns it into rows, the PIVOT then performs the final transformation into columns. The inner query with the UNPIVOT performs the same function as the UNION ALL.
Value for name in (Paul, John, Tim, Eric) If you know all of the values that you want to transform, you can hard-code them into a static version to get the result: select name,, , Then you apply the aggregate function sum() with the case statement to get the new columns for each color.īoth the UNPIVOT and PIVOT functions in SQL server make this transformation much easier. The UNION ALL performs the UNPIVOT of the data by transforming the columns Paul, John, Tim, Eric into separate rows. Sum(case when color = 'Blue' then value else 0 end) Blue Sum(case when color = 'Green' then value else 0 end) Green,
Sum(case when color = 'Red' then value else 0 end) Red, Union All, Aggregate and CASE Version: select name, However, if you do not have access to those functions this can be replicated using UNION ALL to UNPIVOT and then an aggregate function with a CASE statement to PIVOT:Ĭreate Table: CREATE TABLE yourTable( varchar(5), int, int, int, int) In your original post, you stated that PIVOT seems too complex for this scenario, but it can be applied very easily using both the UNPIVOT and PIVOT functions in SQL Server. There are several ways that you can transform this data.
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