For example, we can compute the total sales by employee and the total sales by year:. Note that we could also write GROUPING SETS EmpId, Yr without the extra set of parenthesis, but the extra parenthesis make the intent of the query more explicit and clearly differentiate the previous query from the following query which just performs a normal aggregation by employee and year:.
Thus, the following is not valid:. So both of the following queries compute the same CUBE although the order that the rows are output differs:. This shorthand is most useful when we have more than three dimensions in our schema. For example, suppose we add a month column to our sales table:. The list of column names is optional only if distinct names for all resulting columns are supplied in the query definition.
The following guidelines apply to nonrecursive common table expressions. For guidelines that apply to recursive common table expressions, see Guidelines for Defining and Using Recursive Common Table Expressions that follows. Forward referencing is not allowed. When a CTE is used in a statement that is part of a batch, the statement before it must be followed by a semicolon. When executing a CTE, any hints that reference a CTE may conflict with other hints that are discovered when the CTE accesses its underlying tables, in the same manner as hints that reference views in queries.
When this occurs, the query returns an error. The recursive CTE definition must contain at least two CTE query definitions, an anchor member and a recursive member. Multiple anchor members and recursive members can be defined; however, all anchor member query definitions must be put before the first recursive member definition.
UNION ALL is the only set operator allowed between the last anchor member and first recursive member, and when combining multiple recursive members. The data type of a column in the recursive member must be the same as the data type of the corresponding column in the anchor member.
An incorrectly composed recursive CTE may cause an infinite loop. For example, if the recursive member query definition returns the same values for both the parent and child columns, an infinite loop is created. This lets you control the execution of the statement until you resolve the code problem that is creating the loop.
The server-wide default is When 0 is specified, no limit is applied. Cursors may be defined on queries using CTEs. Only fast forward-only and static snapshot cursors are allowed for recursive CTEs.
If another cursor type is specified in a recursive CTE, the cursor type is converted to static. Tables on remote servers may be referenced in the CTE. Total Size: 0. Back Next. Microsoft recommends you install a download manager. Microsoft Download Manager. Manage all your internet downloads with this easy-to-use manager. It features a simple interface with many customizable options:.
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Why should I install the Microsoft Download Manager? In this case, you will have to download the files individually. You would have the opportunity to download individual files on the "Thank you for downloading" page after completing your download. Files larger than 1 GB may take much longer to download and might not download correctly.
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