![]() I then specify SalesRegion as the pivot column and pass in the column’s values to the IN operator. This will give me values such as 2014_east and 2014_west. In this case, I’m concatenating the SalesYear and Region columns to produce the SalesRegion computed column. To demonstrate this, let’s create our temporary table once more: It’s true that you can’t use the COUNT aggregate function with an asterisk in your PIVOT clause, but you can use the function if you specify a one of the columns in the dataset. “Is there a way to work around SQL Server’s restriction against using COUNT(*) in the PIVOT clause?” Once again, the key to making this all work is to ensure that you get your table expression right so that you’re controlling the columns on which you group the data. However, as in the previous examples, the PIVOT clause specifies only the BookSales and SalesYear columns, which means the data will be grouped by the BookType and BookSubtype columns when it is pivoted, as shown in the following results: The table expression defines our dataset, which includes the BookSubtype column. For example, the following PIVOT clause uses the AVG function: In the preceding example, I used the SUM function to aggregate the data, but we can use a different aggregate function. (We’ll cover grouping more in depth in a separate question.) SQL Server automatically grouped the data by the values in this column, even though the column is not explicitly included in the PIVOT clause. The BookSales values are aggregated according to year, with the data grouping based on the BookType column. The following table shows the results returned by the SELECT statement:Īn important point to note about the results is that the first column is BookType, with a row for fiction sales and a row for nonfiction sales. If you refer back to the syntax above, you can see that BookSales is the aggregate column, SalesYear is the pivot column, and the SalesYear values, which are passed into the IN operator, become the new columns. Let’s start with the following temporary table and data: This will all make more sense when you see it in action. The values you specify here must exist in the pivot column or they will be ignored. The FOR subclause also includes the IN operator, which is where you specify the pivot column values that will be turned into columns. It is this column whose distinct values are turned into their own columns. Next, you define the FOR subclause, which specifies the column on which the pivot will be based. You can use any aggregate function except the COUNT function, when used with an asterisk, as in COUNT(*). The first is the aggregate function and the name of the column to be aggregated. You need to understand how this clause works to make sure your pivots work the way you want.Īfter you specify the PIVOT keyword, you pass in what are essentially three arguments, enclosed in parentheses. For now, let’s focus on the PIVOT clause. You’ll get to see these clauses in action as we progress through the questions. You can also include an ORDER BY clause, but that’s optional. If you use a table expression, then you must also define a table alias. To better understand how this all works, let’s start with the basic syntax for a query that uses the PIVOT operator:įor the SELECT clause, you can specify an asterisk (*) or the individual columns, and for the FROM clause, you can specify a table or table expression. Each unique value in that column becomes its own column, which contains aggregated pivoted data. The data is pivoted based on one of the columns in the dataset. You use the PIVOT operator within your query’s FROM clause to rotate and aggregate the values in a dataset. “How do I use the PIVOT operator to rotate data in SQL Server?” “How do I pivot data if I don’t know the values in the pivoted column?”.“Does the PIVOT operator let you perform multiple aggregations?”.How do I pivot data without using PIVOT?” “I sometimes run queries against a SQL Server 2000 database, which doesn’t support the PIVOT operator.“Is it possible to pivot more than one column when pivoting data in SQL Server?”.“Is there a way to work around SQL Server’s restriction against using COUNT(*) in the PIVOT clause?”.“Can I group data by more than one column when I use the PIVOT operator? “.Is there a way to get around this limitation?” “SQL Server does not permit the use of column expressions in the PIVOT clause.“How do I avoid grouping on a column’s values when pivoting data so I can return a single-row result set that aggregates the entire dataset?”.“I’m confused by how data is grouped when using the PIVOT operator.“Can I specify column names different from the values in the pivoted column?”.“How do I use the PIVOT operator to rotate data in SQL Server?”.Questions About Pivoting Data in SQL Server You Were Too Shy to Ask - Simple Talk Skip to content
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