ChildLink
import type { ChildLink } from "https://googleapis.deno.dev/v1/spanner:v1.ts";
Metadata associated with a parent-child relationship appearing in a PlanNode.
§Properties
The type of the link. For example, in Hash Joins this could be used to distinguish between the build child and the probe child, or in the case of the child being an output variable, to represent the tag associated with the output variable.
Only present if the child node is SCALAR and corresponds to an output
variable of the parent node. The field carries the name of the output
variable. For example, a TableScan
operator that reads rows from a table
will have child links to the SCALAR
nodes representing the output
variables created for each column that is read by the operator. The
corresponding variable
fields will be set to the variable names assigned
to the columns.