Row_number()
window function returns a distinct ordinal number for every row.
SELECT ROW_NUMBER() OVER (ORDER BY …)
FROM …
Variants: without order by
Similar functions: rank()
, dense_rank()
, percent_rank()
, cume_dist()
.
Product specific forms: rownum
(pseudo column).
The row_number()
window function is defined in ISO/IEC 9075:2016-2 as part of optional feature T611, “Elementary OLAP operations”.
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