9.49 OPG_APIS.PR_PREP

Format

OPG_APIS.PR_PREP(
     edge_tab_name   IN VARCHAR2,
     wt_node_pr      IN OUT VARCHAR2,
     wt_node_nextpr  IN OUT VARCHAR2,
     wt_edge_tab_deg IN OUT VARCHAR2,
     wt_delta        IN OUT VARCHAR2,
     options         IN VARCHAR2 DEFAULT NULL);

Description

Prepares for page rank calculations.

Parameters

edge_tab_name

Name of the property graph edge table.

wt_node_pr

Name of the working table to hold the page rank values of the vertices.

wt_node_next_pr

Name of the working table to hold the page rank values of the vertices in the next iteration.

wt_edge_tab_deg

Name of the working table to hold edges and node degree information.

wt_delta

Name of the working table to hold information about some special vertices.

options

Additional settings for the operation. An optional string with one or more (comma-separated) of the following values:

• CREATE_UNDIRECTED=T

• REUSE_UNDIRECTED_TAB=T

Usage Notes

The property graph edge table must exist in the database.

Examples

The following example does the preparation work before running page rank calculations in a property graph named mypg.

set serveroutput on
DECLARE
    wt_pr  varchar2(2000); -- name of the table to hold PR value of the current iteration
    wt_npr varchar2(2000); -- name of the table to hold PR value for the next iteration
    wt3    varchar2(2000); 
    wt4    varchar2(2000);
    wt5    varchar2(2000);
BEGIN
    wt_pr := 'mypgPR';
    opg_apis.pr_prep('mypgGE$', wt_pr, wt_npr, wt3, wt4, null);
    dbms_output.put_line('Working table names  ' || wt_pr 
       || ', wt_npr ' || wt_npr || ', wt3 ' || wt3 || ', wt4 '|| wt4);
END;
/

The output will be similar to the following.

Working table names  "MYPGPR", wt_npr "MYPGGE$$TWPRX277", wt3
"MYPGGE$$TWPRE277", wt4 "MYPGGE$$TWPRD277"