LAG LEAD « Analytical Functions « Oracle PL / SQL

1.LAG() and LEAD(): get a value in a row where that row is a certain number of rows away from the current row
2.The Row Comparison Functions LEAD and LAG
3.The row comparison function can also be partitioned as with other aggregates
4.LAG, LEAD: allow specified offsets and default values for the nulls that result in non-applicable rows
5.lead over order by
6.Lag over
7.Lead over partition
8.Lag over order
9.Use lag over in inner query

10.Use lag over and lead over in inner statement