Class: Google::Cloud::Spanner::V1::PlanNode

Inherits:
Object
  • Object
show all
Extended by:
Protobuf::MessageExts::ClassMethods
Includes:
Protobuf::MessageExts
Defined in:
proto_docs/google/spanner/v1/query_plan.rb

Overview

Node information for nodes appearing in a QueryPlan.plan_nodes.

Defined Under Namespace

Modules: Kind Classes: ChildLink, ShortRepresentation

Instance Attribute Summary collapse

Instance Attribute Details

Returns List of child node indexes and their relationship to this parent.

Returns:



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# File 'proto_docs/google/spanner/v1/query_plan.rb', line 60

class PlanNode
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Metadata associated with a parent-child relationship appearing in a
  # {::Google::Cloud::Spanner::V1::PlanNode PlanNode}.
  # @!attribute [rw] child_index
  #   @return [::Integer]
  #     The node to which the link points.
  # @!attribute [rw] type
  #   @return [::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.
  # @!attribute [rw] variable
  #   @return [::String]
  #     Only present if the child node is {::Google::Cloud::Spanner::V1::PlanNode::Kind::SCALAR 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.
  class ChildLink
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Condensed representation of a node and its subtree. Only present for
  # `SCALAR` [PlanNode(s)][google.spanner.v1.PlanNode].
  # @!attribute [rw] description
  #   @return [::String]
  #     A string representation of the expression subtree rooted at this node.
  # @!attribute [rw] subqueries
  #   @return [::Google::Protobuf::Map{::String => ::Integer}]
  #     A mapping of (subquery variable name) -> (subquery node id) for cases
  #     where the `description` string of this node references a `SCALAR`
  #     subquery contained in the expression subtree rooted at this node. The
  #     referenced `SCALAR` subquery may not necessarily be a direct child of
  #     this node.
  class ShortRepresentation
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # @!attribute [rw] key
    #   @return [::String]
    # @!attribute [rw] value
    #   @return [::Integer]
    class SubqueriesEntry
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The kind of {::Google::Cloud::Spanner::V1::PlanNode PlanNode}. Distinguishes between the two different kinds of
  # nodes that can appear in a query plan.
  module Kind
    # Not specified.
    KIND_UNSPECIFIED = 0

    # Denotes a Relational operator node in the expression tree. Relational
    # operators represent iterative processing of rows during query execution.
    # For example, a `TableScan` operation that reads rows from a table.
    RELATIONAL = 1

    # Denotes a Scalar node in the expression tree. Scalar nodes represent
    # non-iterable entities in the query plan. For example, constants or
    # arithmetic operators appearing inside predicate expressions or references
    # to column names.
    SCALAR = 2
  end
end

#display_name ⇒ ::String

Returns The display name for the node.

Returns:

  • (::String) —

    The display name for the node.



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# File 'proto_docs/google/spanner/v1/query_plan.rb', line 60

class PlanNode
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Metadata associated with a parent-child relationship appearing in a
  # {::Google::Cloud::Spanner::V1::PlanNode PlanNode}.
  # @!attribute [rw] child_index
  #   @return [::Integer]
  #     The node to which the link points.
  # @!attribute [rw] type
  #   @return [::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.
  # @!attribute [rw] variable
  #   @return [::String]
  #     Only present if the child node is {::Google::Cloud::Spanner::V1::PlanNode::Kind::SCALAR 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.
  class ChildLink
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Condensed representation of a node and its subtree. Only present for
  # `SCALAR` [PlanNode(s)][google.spanner.v1.PlanNode].
  # @!attribute [rw] description
  #   @return [::String]
  #     A string representation of the expression subtree rooted at this node.
  # @!attribute [rw] subqueries
  #   @return [::Google::Protobuf::Map{::String => ::Integer}]
  #     A mapping of (subquery variable name) -> (subquery node id) for cases
  #     where the `description` string of this node references a `SCALAR`
  #     subquery contained in the expression subtree rooted at this node. The
  #     referenced `SCALAR` subquery may not necessarily be a direct child of
  #     this node.
  class ShortRepresentation
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # @!attribute [rw] key
    #   @return [::String]
    # @!attribute [rw] value
    #   @return [::Integer]
    class SubqueriesEntry
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The kind of {::Google::Cloud::Spanner::V1::PlanNode PlanNode}. Distinguishes between the two different kinds of
  # nodes that can appear in a query plan.
  module Kind
    # Not specified.
    KIND_UNSPECIFIED = 0

    # Denotes a Relational operator node in the expression tree. Relational
    # operators represent iterative processing of rows during query execution.
    # For example, a `TableScan` operation that reads rows from a table.
    RELATIONAL = 1

    # Denotes a Scalar node in the expression tree. Scalar nodes represent
    # non-iterable entities in the query plan. For example, constants or
    # arithmetic operators appearing inside predicate expressions or references
    # to column names.
    SCALAR = 2
  end
end

#execution_stats ⇒ ::Google::Protobuf::Struct

Returns The execution statistics associated with the node, contained in a group of key-value pairs. Only present if the plan was returned as a result of a profile query. For example, number of executions, number of rows/time per execution etc.

Returns:

  • (::Google::Protobuf::Struct) —

    The execution statistics associated with the node, contained in a group of key-value pairs. Only present if the plan was returned as a result of a profile query. For example, number of executions, number of rows/time per execution etc.



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# File 'proto_docs/google/spanner/v1/query_plan.rb', line 60

class PlanNode
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Metadata associated with a parent-child relationship appearing in a
  # {::Google::Cloud::Spanner::V1::PlanNode PlanNode}.
  # @!attribute [rw] child_index
  #   @return [::Integer]
  #     The node to which the link points.
  # @!attribute [rw] type
  #   @return [::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.
  # @!attribute [rw] variable
  #   @return [::String]
  #     Only present if the child node is {::Google::Cloud::Spanner::V1::PlanNode::Kind::SCALAR 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.
  class ChildLink
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Condensed representation of a node and its subtree. Only present for
  # `SCALAR` [PlanNode(s)][google.spanner.v1.PlanNode].
  # @!attribute [rw] description
  #   @return [::String]
  #     A string representation of the expression subtree rooted at this node.
  # @!attribute [rw] subqueries
  #   @return [::Google::Protobuf::Map{::String => ::Integer}]
  #     A mapping of (subquery variable name) -> (subquery node id) for cases
  #     where the `description` string of this node references a `SCALAR`
  #     subquery contained in the expression subtree rooted at this node. The
  #     referenced `SCALAR` subquery may not necessarily be a direct child of
  #     this node.
  class ShortRepresentation
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # @!attribute [rw] key
    #   @return [::String]
    # @!attribute [rw] value
    #   @return [::Integer]
    class SubqueriesEntry
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The kind of {::Google::Cloud::Spanner::V1::PlanNode PlanNode}. Distinguishes between the two different kinds of
  # nodes that can appear in a query plan.
  module Kind
    # Not specified.
    KIND_UNSPECIFIED = 0

    # Denotes a Relational operator node in the expression tree. Relational
    # operators represent iterative processing of rows during query execution.
    # For example, a `TableScan` operation that reads rows from a table.
    RELATIONAL = 1

    # Denotes a Scalar node in the expression tree. Scalar nodes represent
    # non-iterable entities in the query plan. For example, constants or
    # arithmetic operators appearing inside predicate expressions or references
    # to column names.
    SCALAR = 2
  end
end

#index ⇒ ::Integer

Returns The PlanNode's index in node list.

Returns:

  • (::Integer) —

    The PlanNode's index in node list.



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# File 'proto_docs/google/spanner/v1/query_plan.rb', line 60

class PlanNode
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Metadata associated with a parent-child relationship appearing in a
  # {::Google::Cloud::Spanner::V1::PlanNode PlanNode}.
  # @!attribute [rw] child_index
  #   @return [::Integer]
  #     The node to which the link points.
  # @!attribute [rw] type
  #   @return [::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.
  # @!attribute [rw] variable
  #   @return [::String]
  #     Only present if the child node is {::Google::Cloud::Spanner::V1::PlanNode::Kind::SCALAR 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.
  class ChildLink
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Condensed representation of a node and its subtree. Only present for
  # `SCALAR` [PlanNode(s)][google.spanner.v1.PlanNode].
  # @!attribute [rw] description
  #   @return [::String]
  #     A string representation of the expression subtree rooted at this node.
  # @!attribute [rw] subqueries
  #   @return [::Google::Protobuf::Map{::String => ::Integer}]
  #     A mapping of (subquery variable name) -> (subquery node id) for cases
  #     where the `description` string of this node references a `SCALAR`
  #     subquery contained in the expression subtree rooted at this node. The
  #     referenced `SCALAR` subquery may not necessarily be a direct child of
  #     this node.
  class ShortRepresentation
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # @!attribute [rw] key
    #   @return [::String]
    # @!attribute [rw] value
    #   @return [::Integer]
    class SubqueriesEntry
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The kind of {::Google::Cloud::Spanner::V1::PlanNode PlanNode}. Distinguishes between the two different kinds of
  # nodes that can appear in a query plan.
  module Kind
    # Not specified.
    KIND_UNSPECIFIED = 0

    # Denotes a Relational operator node in the expression tree. Relational
    # operators represent iterative processing of rows during query execution.
    # For example, a `TableScan` operation that reads rows from a table.
    RELATIONAL = 1

    # Denotes a Scalar node in the expression tree. Scalar nodes represent
    # non-iterable entities in the query plan. For example, constants or
    # arithmetic operators appearing inside predicate expressions or references
    # to column names.
    SCALAR = 2
  end
end

#kind ⇒ ::Google::Cloud::Spanner::V1::PlanNode::Kind

Returns Used to determine the type of node. May be needed for visualizing different kinds of nodes differently. For example, If the node is a SCALAR node, it will have a condensed representation which can be used to directly embed a description of the node in its parent.

Returns:

  • (::Google::Cloud::Spanner::V1::PlanNode::Kind) —

    Used to determine the type of node. May be needed for visualizing different kinds of nodes differently. For example, If the node is a SCALAR node, it will have a condensed representation which can be used to directly embed a description of the node in its parent.



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# File 'proto_docs/google/spanner/v1/query_plan.rb', line 60

class PlanNode
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Metadata associated with a parent-child relationship appearing in a
  # {::Google::Cloud::Spanner::V1::PlanNode PlanNode}.
  # @!attribute [rw] child_index
  #   @return [::Integer]
  #     The node to which the link points.
  # @!attribute [rw] type
  #   @return [::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.
  # @!attribute [rw] variable
  #   @return [::String]
  #     Only present if the child node is {::Google::Cloud::Spanner::V1::PlanNode::Kind::SCALAR 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.
  class ChildLink
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Condensed representation of a node and its subtree. Only present for
  # `SCALAR` [PlanNode(s)][google.spanner.v1.PlanNode].
  # @!attribute [rw] description
  #   @return [::String]
  #     A string representation of the expression subtree rooted at this node.
  # @!attribute [rw] subqueries
  #   @return [::Google::Protobuf::Map{::String => ::Integer}]
  #     A mapping of (subquery variable name) -> (subquery node id) for cases
  #     where the `description` string of this node references a `SCALAR`
  #     subquery contained in the expression subtree rooted at this node. The
  #     referenced `SCALAR` subquery may not necessarily be a direct child of
  #     this node.
  class ShortRepresentation
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # @!attribute [rw] key
    #   @return [::String]
    # @!attribute [rw] value
    #   @return [::Integer]
    class SubqueriesEntry
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The kind of {::Google::Cloud::Spanner::V1::PlanNode PlanNode}. Distinguishes between the two different kinds of
  # nodes that can appear in a query plan.
  module Kind
    # Not specified.
    KIND_UNSPECIFIED = 0

    # Denotes a Relational operator node in the expression tree. Relational
    # operators represent iterative processing of rows during query execution.
    # For example, a `TableScan` operation that reads rows from a table.
    RELATIONAL = 1

    # Denotes a Scalar node in the expression tree. Scalar nodes represent
    # non-iterable entities in the query plan. For example, constants or
    # arithmetic operators appearing inside predicate expressions or references
    # to column names.
    SCALAR = 2
  end
end

#metadata ⇒ ::Google::Protobuf::Struct

Returns Attributes relevant to the node contained in a group of key-value pairs. For example, a Parameter Reference node could have the following information in its metadata:

{
  "parameter_reference": "param1",
  "parameter_type": "array"
}.

Returns:

  • (::Google::Protobuf::Struct) —

    Attributes relevant to the node contained in a group of key-value pairs. For example, a Parameter Reference node could have the following information in its metadata:

    {
  "parameter_reference": "param1",
  "parameter_type": "array"
}



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# File 'proto_docs/google/spanner/v1/query_plan.rb', line 60

class PlanNode
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Metadata associated with a parent-child relationship appearing in a
  # {::Google::Cloud::Spanner::V1::PlanNode PlanNode}.
  # @!attribute [rw] child_index
  #   @return [::Integer]
  #     The node to which the link points.
  # @!attribute [rw] type
  #   @return [::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.
  # @!attribute [rw] variable
  #   @return [::String]
  #     Only present if the child node is {::Google::Cloud::Spanner::V1::PlanNode::Kind::SCALAR 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.
  class ChildLink
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Condensed representation of a node and its subtree. Only present for
  # `SCALAR` [PlanNode(s)][google.spanner.v1.PlanNode].
  # @!attribute [rw] description
  #   @return [::String]
  #     A string representation of the expression subtree rooted at this node.
  # @!attribute [rw] subqueries
  #   @return [::Google::Protobuf::Map{::String => ::Integer}]
  #     A mapping of (subquery variable name) -> (subquery node id) for cases
  #     where the `description` string of this node references a `SCALAR`
  #     subquery contained in the expression subtree rooted at this node. The
  #     referenced `SCALAR` subquery may not necessarily be a direct child of
  #     this node.
  class ShortRepresentation
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # @!attribute [rw] key
    #   @return [::String]
    # @!attribute [rw] value
    #   @return [::Integer]
    class SubqueriesEntry
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The kind of {::Google::Cloud::Spanner::V1::PlanNode PlanNode}. Distinguishes between the two different kinds of
  # nodes that can appear in a query plan.
  module Kind
    # Not specified.
    KIND_UNSPECIFIED = 0

    # Denotes a Relational operator node in the expression tree. Relational
    # operators represent iterative processing of rows during query execution.
    # For example, a `TableScan` operation that reads rows from a table.
    RELATIONAL = 1

    # Denotes a Scalar node in the expression tree. Scalar nodes represent
    # non-iterable entities in the query plan. For example, constants or
    # arithmetic operators appearing inside predicate expressions or references
    # to column names.
    SCALAR = 2
  end
end

#short_representation ⇒ ::Google::Cloud::Spanner::V1::PlanNode::ShortRepresentation

Returns Condensed representation for SCALAR nodes.

Returns:



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# File 'proto_docs/google/spanner/v1/query_plan.rb', line 60

class PlanNode
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Metadata associated with a parent-child relationship appearing in a
  # {::Google::Cloud::Spanner::V1::PlanNode PlanNode}.
  # @!attribute [rw] child_index
  #   @return [::Integer]
  #     The node to which the link points.
  # @!attribute [rw] type
  #   @return [::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.
  # @!attribute [rw] variable
  #   @return [::String]
  #     Only present if the child node is {::Google::Cloud::Spanner::V1::PlanNode::Kind::SCALAR 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.
  class ChildLink
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Condensed representation of a node and its subtree. Only present for
  # `SCALAR` [PlanNode(s)][google.spanner.v1.PlanNode].
  # @!attribute [rw] description
  #   @return [::String]
  #     A string representation of the expression subtree rooted at this node.
  # @!attribute [rw] subqueries
  #   @return [::Google::Protobuf::Map{::String => ::Integer}]
  #     A mapping of (subquery variable name) -> (subquery node id) for cases
  #     where the `description` string of this node references a `SCALAR`
  #     subquery contained in the expression subtree rooted at this node. The
  #     referenced `SCALAR` subquery may not necessarily be a direct child of
  #     this node.
  class ShortRepresentation
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # @!attribute [rw] key
    #   @return [::String]
    # @!attribute [rw] value
    #   @return [::Integer]
    class SubqueriesEntry
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The kind of {::Google::Cloud::Spanner::V1::PlanNode PlanNode}. Distinguishes between the two different kinds of
  # nodes that can appear in a query plan.
  module Kind
    # Not specified.
    KIND_UNSPECIFIED = 0

    # Denotes a Relational operator node in the expression tree. Relational
    # operators represent iterative processing of rows during query execution.
    # For example, a `TableScan` operation that reads rows from a table.
    RELATIONAL = 1

    # Denotes a Scalar node in the expression tree. Scalar nodes represent
    # non-iterable entities in the query plan. For example, constants or
    # arithmetic operators appearing inside predicate expressions or references
    # to column names.
    SCALAR = 2
  end
end