lag
Returns a value evaluated at the row that is at a specified physical offset before the current row within the ordered frame.
This function is similar to lagInFrame
, but always uses the ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING
frame.
Syntax
For more detail on window function syntax see: Window Functions - Syntax.
Parameters
x
— Column name.offset
— Offset to apply. (U)Int*. (Optional -1
by default).default
— Value to return if calculated row exceeds the boundaries of the window frame. (Optional - default value of column type when omitted).
Returned value
- Value evaluated at the row that is at a specified physical offset before the current row within the ordered frame.
Example
This example looks at historical data for a specific stock and uses the lag
function to calculate a day-to-day delta and percentage change in the closing price of the stock.