The default frame specification is `groups from unbounded preceding to current row` or `range from unbounded preceding to current row` (both of which apply count to the number of rows in the peer groups included, including all the rows in the peer group to which the current row belongs), thus count() works like rank() except that it returns the number of the last row for each peer group. If a frame specification is given, then that frame specification in used. PARTITION BY and ORDER BY work as expected. Thank you.Īctually, what appears to happen (by observation and experimentation) is that count() has behaviour that is dependent on the window specification. What I want is each row to include the row number as well as the total number of rows in the window. But instead, there seems to be some automatic partitioning going on based on the value of x.Īm I misunderstanding the documentation on Window functions? Or am I using count() wrong? Any help would be appreciated. If there is no PARTITION BY clause, then the entire result set of the query is a single partition.īased on the last sentence, I expected the count() to operate over all the rows in the window since it should be considered a single partition. A partition consists of all rows that have the same value for all terms of the PARTITION BY clause in the window-defn. This is even though my window definition does not include a Partition by clause, and the documentation for window functions says the following:įor the purpose of computing window functions, the result set of a query is divided into one or more "partitions". Instead, count() seems to be partitioning the window by the value of x. I expect the select query to have 12 under TotalRows in all rows of the output. Select x, row_number() over Win1 as Row, count() over Win1 as TotalRowsġ2 values have been inserted into table Test. Please consider the following set of simple queries:
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