com.sun.mdm.index.master.search.merge
Class MergeHistoryHelper

java.lang.Object
  com.sun.mdm.index.master.search.merge.MergeHistoryHelper

public class MergeHistoryHelper

extends java.lang.Object

Helper class to traverse merge history

Constructor Summary

MergeHistoryHelper(TransactionMgr transMgr)
Creates a new instance of MergeHistoryHelper

Method Summary

java.lang.String	getActiveEUID(java.sql.Connection con, java.lang.String sourceEUID) Search the merge tree and find the active EUID associated with the merged EUID.
java.lang.String	getActiveEUIDHelper(java.sql.PreparedStatement selectActiveEUIDTimestamp, java.lang.String sourceEUID, java.sql.Timestamp ts) Search the merge tree and find the active EUID associated with the merged EUID.
MergeHistoryNode	getMergeHistory(java.sql.Connection con, java.lang.String euid) This method populates the MergeHistoryNode object based on the root EUID that is passed to it.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MergeHistoryHelper

public MergeHistoryHelper(TransactionMgr transMgr)

Creates a new instance of MergeHistoryHelper

Parameters:

transMgr - handle to transaction manager

Method Detail

getActiveEUID

public java.lang.String getActiveEUID(java.sql.Connection con,
                                      java.lang.String sourceEUID)
                               throws java.sql.SQLException

Search the merge tree and find the active EUID associated with the merged EUID.

Parameters:

con - Connection handle to database

sourceEUID - EUID of merged record

Returns:

Returns EUID record that pairs with the merged EUID of a merged event

Throws:

java.sql.SQLException - An error occured.

getActiveEUIDHelper

public java.lang.String getActiveEUIDHelper(java.sql.PreparedStatement selectActiveEUIDTimestamp,
                                            java.lang.String sourceEUID,
                                            java.sql.Timestamp ts)
                                     throws java.sql.SQLException

Search the merge tree and find the active EUID associated with the merged EUID. The timestamp is used to prevent circular references.

Parameters:

selectActiveEUIDTimestamp - Prepared statement for selcting the active EUID.

sourceEUID - EUID of merged record

ts - Timestamp of the last of merge.

Returns:

Returns EUID record that pairs with the merged EUID of a merged event

Throws:

java.sql.SQLException - An error occured.

getMergeHistory

public MergeHistoryNode getMergeHistory(java.sql.Connection con,
                                        java.lang.String euid)
                                 throws java.sql.SQLException,
                                        OPSException

This method populates the MergeHistoryNode object based on the root EUID that is passed to it. The main table that is used to determine the merge history is SBYN_MERGETRANS. To demonstrate how this function is used, an example will be used. Suppose the following merges have been performed: F merged to C (C survives) at time 1 B merged to A (A survives) at time 2 C merged to A (A survives) at time 3 G merged to D (D survives) at time 4 A merged to D (D survives) at time 5 D merged to E (E survives) at time 6 The mrg trans table will appear as follows: Dest Source TransId (survivor) (merged) --------------------------------------------- C F 1 A B 2 A C 3 D G 4 D A 5 E D 6 The desired merge tree is: E |--E |--D |--D | |--D | |--G |--A |--A | |--A | |--B |--C |--C |--F In order to translate the sbyn_mrg_trans table into this tree, a list was created to hold EUID's and handles for both merged and survivor records. The code in this event populates the list as follows: 1 2 3 4 5 6 7 ---------------------------------------------------------- Dest_EUID E E D D A A C Source_UID D A G C B F To achieve this result the following algorithm was used: 1) Search mrg trans for all EUID's that equal root 2) Populate the list with the survivor and merged EUIDs of the result set 1 2 3 4 5 6 7 ---------------------------------------------------------- Dest_EUID E E Source_EUID D 3) Now search for all EUID's in mrg trans that equal the merged EUID 4) Populate the list with the survivor and merged EUID's of the result set (sorted by transaction id) 1 2 3 4 5 6 7 ---------------------------------------------------------- Dest_EUID E E D D Source_EUID D A G 5) Now search for all EUID's in mrg trans that equal the added merged EUID's (A, G) 6) Populate the list with the survivor and merged UID's of the result set (sorted by transaction id) 1 2 3 4 5 6 7 ---------------------------------------------------------- Dest_EUID E E D D A A Source_EUID D A G C B 5) Now search for all EUID's in mrg trans that equal the added merged EUID's (C, B) 6) Populate the list with the survivor and merged EUID's of the result set (sorted by transaction id) 1 2 3 4 5 6 7 ---------------------------------------------------------- Dest_EUID E E D D A A C Source_EUID D A G C B F 7) The above algorithm is executed as a loop until no new records are added to list 8) Do While list pointer <= size of list Set list pointer to next row. Find record in list where (survivor EUID or merged EUID = the survivor EUID of the current row) AND list_row < current row. IF survivor EUID = the survivor of the EUID of the current row THEN Add the item as a child of the survivor UEID ELSE Add the item as a child of the merged EUID END IF

Parameters:

con - Connection handle

euid - EUID

Returns:

Merge history

Throws:

java.sql.SQLException - An error occured.

OPSException - An error occured.