oracle.pgx.api

Interface Operation

public interface Operation

An operation is part of an execution plan for executing a PGQL query. The execution plan is composed of a tree of operations.

Method Summary

Modifier and Type	Method and Description
double	getCardinalityEstimate() A cardinality estimate is the expected number of results after executing this operation
java.util.List<Operation>	getChildren() Non leaf operations can have multiple child operations, which will be returned by this function
double	getCostEstimate()
oracle.pgx.common.PgxId	getGraphId() Gives the graph used in the operation
OperationType	getOperationType() Gives the type of operation
java.lang.String	getPatternInfo() An operation can match a specific part of the query with a graph.
double	getTotalCostEstimate()
boolean	isSameQueryPlan(Operation other) Check if the query plan with this operation as root node is equal to the query plan with 'other' as root node.
void	print() Print the current operation and all its children to standard output
void	print(java.io.PrintStream printStream) Print the current operation and all its children to the given printStream

Method Detail

getCardinalityEstimate

double getCardinalityEstimate()

A cardinality estimate is the expected number of results after executing this operation

Returns:

an estimation of the cardinality after executing this operation

getChildren

java.util.List<Operation> getChildren()

Non leaf operations can have multiple child operations, which will be returned by this function

Returns:

a list of operations which are the children of this operation

getCostEstimate

double getCostEstimate()

Returns:

an estimation of the cost of executing this operation

getGraphId

oracle.pgx.common.PgxId getGraphId()

Gives the graph used in the operation

Returns:

the id of the graph used in the operation

getOperationType

OperationType getOperationType()

Gives the type of operation

Returns:

operationType of this operation as an enum value

getPatternInfo

java.lang.String getPatternInfo()

An operation can match a specific part of the query with a graph. This function will show what part of the query is matched during this operation.

Returns:

an string indicating the pattern that will be matched by this operation

getTotalCostEstimate

double getTotalCostEstimate()

Returns:

an estimation of the cost of executing this operation and all its children

isSameQueryPlan

boolean isSameQueryPlan(Operation other)

Check if the query plan with this operation as root node is equal to the query plan with 'other' as root node. This will only check if the operationType and the pattern are the same for each node in both query plans.

Returns:

true if both execution plans are the same, false otherwise

print

void print()

Print the current operation and all its children to standard output

print

void print(java.io.PrintStream printStream)

Print the current operation and all its children to the given printStream

Parameters:

printStream - Location of the output