Reference documentation and code samples for the Cloud Spanner V1 Client class ChildLink.
Metadata associated with a parent-child relationship appearing in a
PlanNode.
Generated from protobuf message google.spanner.v1.PlanNode.ChildLink
Namespace
Google \ Cloud \ Spanner \ V1 \ PlanNode
Methods
__construct
Constructor.
Parameters
Name
Description
data
array
Optional. Data for populating the Message object.
↳ child_index
int
The node to which the link points.
↳ type
string
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.
↳ variable
string
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.
getChildIndex
The node to which the link points.
Returns
Type
Description
int
setChildIndex
The node to which the link points.
Parameter
Name
Description
var
int
Returns
Type
Description
$this
getType
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.
Returns
Type
Description
string
setType
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.
Parameter
Name
Description
var
string
Returns
Type
Description
$this
getVariable
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.
Returns
Type
Description
string
setVariable
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.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[],[],null,["# Cloud Spanner V1 Client - Class ChildLink (1.104.0)\n\nVersion latestkeyboard_arrow_down\n\n- [1.104.0 (latest)](/php/docs/reference/cloud-spanner/latest/V1.PlanNode.ChildLink)\n- [1.103.0](/php/docs/reference/cloud-spanner/1.103.0/V1.PlanNode.ChildLink)\n- [1.102.0](/php/docs/reference/cloud-spanner/1.102.0/V1.PlanNode.ChildLink)\n- [1.101.0](/php/docs/reference/cloud-spanner/1.101.0/V1.PlanNode.ChildLink)\n- [1.100.0](/php/docs/reference/cloud-spanner/1.100.0/V1.PlanNode.ChildLink)\n- [1.98.0](/php/docs/reference/cloud-spanner/1.98.0/V1.PlanNode.ChildLink)\n- [1.97.0](/php/docs/reference/cloud-spanner/1.97.0/V1.PlanNode.ChildLink)\n- [1.96.0](/php/docs/reference/cloud-spanner/1.96.0/V1.PlanNode.ChildLink)\n- [1.95.0](/php/docs/reference/cloud-spanner/1.95.0/V1.PlanNode.ChildLink)\n- [1.94.0](/php/docs/reference/cloud-spanner/1.94.0/V1.PlanNode.ChildLink)\n- [1.93.1](/php/docs/reference/cloud-spanner/1.93.1/V1.PlanNode.ChildLink)\n- [1.92.1](/php/docs/reference/cloud-spanner/1.92.1/V1.PlanNode.ChildLink)\n- [1.91.0](/php/docs/reference/cloud-spanner/1.91.0/V1.PlanNode.ChildLink)\n- [1.90.0](/php/docs/reference/cloud-spanner/1.90.0/V1.PlanNode.ChildLink)\n- [1.89.0](/php/docs/reference/cloud-spanner/1.89.0/V1.PlanNode.ChildLink)\n- [1.88.0](/php/docs/reference/cloud-spanner/1.88.0/V1.PlanNode.ChildLink)\n- [1.87.0](/php/docs/reference/cloud-spanner/1.87.0/V1.PlanNode.ChildLink)\n- [1.86.0](/php/docs/reference/cloud-spanner/1.86.0/V1.PlanNode.ChildLink)\n- [1.85.0](/php/docs/reference/cloud-spanner/1.85.0/V1.PlanNode.ChildLink)\n- [1.84.0](/php/docs/reference/cloud-spanner/1.84.0/V1.PlanNode.ChildLink)\n- [1.83.0](/php/docs/reference/cloud-spanner/1.83.0/V1.PlanNode.ChildLink)\n- [1.82.0](/php/docs/reference/cloud-spanner/1.82.0/V1.PlanNode.ChildLink)\n- [1.81.0](/php/docs/reference/cloud-spanner/1.81.0/V1.PlanNode.ChildLink)\n- [1.80.0](/php/docs/reference/cloud-spanner/1.80.0/V1.PlanNode.ChildLink)\n- [1.79.0](/php/docs/reference/cloud-spanner/1.79.0/V1.PlanNode.ChildLink)\n- [1.78.0](/php/docs/reference/cloud-spanner/1.78.0/V1.PlanNode.ChildLink)\n- [1.77.0](/php/docs/reference/cloud-spanner/1.77.0/V1.PlanNode.ChildLink)\n- [1.76.1](/php/docs/reference/cloud-spanner/1.76.1/V1.PlanNode.ChildLink)\n- [1.68.0](/php/docs/reference/cloud-spanner/1.68.0/V1.PlanNode.ChildLink)\n- [1.67.0](/php/docs/reference/cloud-spanner/1.67.0/V1.PlanNode.ChildLink)\n- [1.66.0](/php/docs/reference/cloud-spanner/1.66.0/V1.PlanNode.ChildLink)\n- [1.65.0](/php/docs/reference/cloud-spanner/1.65.0/V1.PlanNode.ChildLink)\n- [1.64.0](/php/docs/reference/cloud-spanner/1.64.0/V1.PlanNode.ChildLink)\n- [1.63.2](/php/docs/reference/cloud-spanner/1.63.2/V1.PlanNode.ChildLink)\n- [1.62.1](/php/docs/reference/cloud-spanner/1.62.1/V1.PlanNode.ChildLink)\n- [1.61.0](/php/docs/reference/cloud-spanner/1.61.0/V1.PlanNode.ChildLink)\n- [1.60.0](/php/docs/reference/cloud-spanner/1.60.0/V1.PlanNode.ChildLink)\n- [1.59.0](/php/docs/reference/cloud-spanner/1.59.0/V1.PlanNode.ChildLink)\n- [1.58.4](/php/docs/reference/cloud-spanner/1.58.4/V1.PlanNode.ChildLink)\n- [1.57.0](/php/docs/reference/cloud-spanner/1.57.0/V1.PlanNode.ChildLink)\n- [1.56.0](/php/docs/reference/cloud-spanner/1.56.0/V1.PlanNode.ChildLink)\n- [1.55.0](/php/docs/reference/cloud-spanner/1.55.0/V1.PlanNode.ChildLink)\n- [1.54.2](/php/docs/reference/cloud-spanner/1.54.2/V1.PlanNode.ChildLink) \nReference documentation and code samples for the Cloud Spanner V1 Client class ChildLink.\n\nMetadata associated with a parent-child relationship appearing in a\n[PlanNode](/php/docs/reference/cloud-spanner/latest/V1.PlanNode).\n\nGenerated from protobuf message `google.spanner.v1.PlanNode.ChildLink`\n\nNamespace\n---------\n\nGoogle \\\\ Cloud \\\\ Spanner \\\\ V1 \\\\ PlanNode\n\nMethods\n-------\n\n### __construct\n\nConstructor.\n\n### getChildIndex\n\nThe node to which the link points.\n\n### setChildIndex\n\nThe node to which the link points.\n\n### getType\n\nThe type of the link. For example, in Hash Joins this could be used to\ndistinguish between the build child and the probe child, or in the case\nof the child being an output variable, to represent the tag associated\nwith the output variable.\n\n### setType\n\nThe type of the link. For example, in Hash Joins this could be used to\ndistinguish between the build child and the probe child, or in the case\nof the child being an output variable, to represent the tag associated\nwith the output variable.\n\n### getVariable\n\nOnly present if the child node is [SCALAR](/php/docs/reference/cloud-spanner/latest/V1.PlanNode.Kind#_Google_Cloud_Spanner_V1_PlanNode_Kind__SCALAR) and corresponds\nto an output variable of the parent node. The field carries the name of\nthe output variable.\n\nFor example, a `TableScan` operator that reads rows from a table will\nhave child links to the `SCALAR` nodes representing the output variables\ncreated for each column that is read by the operator. The corresponding\n`variable` fields will be set to the variable names assigned to the\ncolumns.\n\n### setVariable\n\nOnly present if the child node is [SCALAR](/php/docs/reference/cloud-spanner/latest/V1.PlanNode.Kind#_Google_Cloud_Spanner_V1_PlanNode_Kind__SCALAR) and corresponds\nto an output variable of the parent node. The field carries the name of\nthe output variable.\n\nFor example, a `TableScan` operator that reads rows from a table will\nhave child links to the `SCALAR` nodes representing the output variables\ncreated for each column that is read by the operator. The corresponding\n`variable` fields will be set to the variable names assigned to the\ncolumns."]]