Cloud Spanner V1 Client - Class ChildLink (1.54.2)

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

Methods

Constructor.

Parameters
NameDescription
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.

The node to which the link points.

Generated from protobuf field int32 child_index = 1;

Returns
TypeDescription
int

The node to which the link points.

Generated from protobuf field int32 child_index = 1;

Parameter
NameDescription
var int
Returns
TypeDescription
$this

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.

Generated from protobuf field string type = 2;

Returns
TypeDescription
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.

Generated from protobuf field string type = 2;

Parameter
NameDescription
var string
Returns
TypeDescription
$this

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.

Generated from protobuf field string variable = 3;

Returns
TypeDescription
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.

Generated from protobuf field string variable = 3;

Parameter
NameDescription
var string
Returns
TypeDescription
$this