LEAD

LEAD provides access to more than one row of a table at the same time without a self-join. Given a series of rows returned from a query and a position of the cursor, LEAD provides access to a row at a given physical offset beyond that position.

Syntax

LEAD (expression [, offset_expression [, default_expression ] ] ) [IGNORE NULLS] OVER ( [ PARTITION BY expression [, ...] ]

 ORDER BY expression [ ASC | DESC ] [ NULLS { FIRST | LAST } [, ...] )

Remarks

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IGNORE NULLS and PARTITION BY are optional.

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ORDER BY is required.

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The window clause is not allowed.