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][google.spanner.v1.PlanNode.Kind.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.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-07 UTC."],[[["\u003cp\u003eThis document outlines the \u003ccode\u003eChildLink\u003c/code\u003e class, which is part of the \u003ccode\u003eGoogle.Cloud.Spanner.V1\u003c/code\u003e namespace, specifically within the context of \u003ccode\u003ePlanNode.Types\u003c/code\u003e, and is used to represent the parent-child relationships within a \u003ccode\u003ePlanNode\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eChildLink\u003c/code\u003e class implements several interfaces including \u003ccode\u003eIMessage\u003c/code\u003e, \u003ccode\u003eIEquatable\u003c/code\u003e, \u003ccode\u003eIDeepCloneable\u003c/code\u003e, and \u003ccode\u003eIBufferMessage\u003c/code\u003e, and inherits from the \u003ccode\u003eObject\u003c/code\u003e class, providing functionalities for message handling, equality checks, deep cloning, and buffer operations.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eChildLink\u003c/code\u003e class has two constructors, a default one and one that takes another \u003ccode\u003eChildLink\u003c/code\u003e object as a parameter for copying.\u003c/p\u003e\n"],["\u003cp\u003eThe class includes properties such as \u003ccode\u003eChildIndex\u003c/code\u003e (an integer representing the linked node), \u003ccode\u003eType\u003c/code\u003e (a string describing the link type), and \u003ccode\u003eVariable\u003c/code\u003e (a string representing the output variable name, relevant when the child node is a scalar).\u003c/p\u003e\n"],["\u003cp\u003eThe latest version available is \u003ccode\u003e5.0.0-beta05\u003c/code\u003e, and the webpage lists multiple previous versions from \u003ccode\u003e5.0.0-beta04\u003c/code\u003e all the way down to \u003ccode\u003e3.5.0\u003c/code\u003e.\u003c/p\u003e\n"]]],[],null,[]]
