Archive for March 10th, 2009
In the previous articles I wrote about emulating some of the analytic functions in MySQL.
Today, I’ll write about four more userful functions:
These functions also do not have aggregate analogs.
FIRST VALUE(column) returns the value of column from the first row of the grouping set.
LAST_VALUE(column) returns the value of column from the last row of the grouping set.
This can be illustrated by the following query:
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