next

Knowledge Checkpoint

Readings that will help you understand this documentation better:

• Window Functions Overview

Definition

A window function that returns the value of the next row at an offset relative to the current row.

Syntax

next(expr, offset, order: order_expr, ...)
next(expr, offset, order: order_expr, ...)
next(expr, offset, order: order_expr, ..., reset: partition_expr, ...)
next(expr, offset, order: order_expr, ..., partition: partition_expr, ...)

Examples

next(count(users.id), order: count(users.id) | desc())
next(count(users.id), 2, order: users.created_at | month())
next(count(users.id), 4, order: users.created_at | month(), reset: users.gender)

// Axis-aware examples
next(revenue, order: 'rows')                          // Next row value
next(revenue, 2, order: 'columns', partition: 'rows') // Two columns ahead within each row
next(sales, order: 'x_axis' | desc())                 // Next value in reverse order

Input

• expr (required): An expression of the value
• offset (optional): The offset of the next row relative to the current row. If not specified, the default value is 1.
• order (required, repeatable): A field that is used for ordering. The order defaults to ascending. The order can be set explicitly with asc() or desc(). You can also use axis references:
  • 'rows' or 'x_axis': Order by dimensions mapped to rows/x-axis
  • 'columns' or 'legend': Order by dimensions mapped to columns/legend
  • Axis references can be modified with asc() or desc(): order: 'rows' | desc()
  warning

  If the specified order does not uniquely identify rows, the result of the function can be non-deterministic. For example, if you use order: users.age, and there are multiple users with the same age in the same partition, the result can be unexpected.

• partition or reset (repeatable, optional): A field that is used for partitioning the table. You can also use axis references like 'rows', 'columns', 'x_axis', or 'legend'. If partitions are not specified:
  • If order is specified, the table will be partitioned by all other grouping columns.
  • If order is not specified, the table will be considered as a single partition.

Output

The value of the next row in a offset relative to the current row.

Sample Usages

Please refer to the sample usages in previous.