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 \ PlanNodeMethods
__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 |
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.
| Parameter | |
|---|---|
| Name | Description |
var |
string
|
| Returns | |
|---|---|
| Type | Description |
$this |
|