9 Synchronization with Relational Database Tables

This chapter explains how to synchronize data to Oracle Internet Directory from tables in a relational database. The synchronization can be either incremental—for example, one database table row at a time—or all the database tables at once. The process of synchronization with a database server involves executing a directory integration profile. This process has two steps:

1. Retrieving the data from the database. This involves executing a SQL SELECT statement that retrieves the specified data records from the database.

2. Writing the data into the directory. This involves converting the retrieved data records to LDAP attribute values and performing the LDAP operation on the directory.

Note: Before reading this chapter, be sure to familiarize yourself with the introductory chapters about Directory Integration and Provisioning—specifically: Chapter 1, "Introduction to Oracle Identity Management Integration" Chapter 5, "Oracle Directory Synchronization Service" Also, be aware that Oracle Internet Directory 10g Release 2 (10.1.2) does not enable exporting data from Oracle Internet Directory to a relational database.

This chapter contains these topics:

• Preparing the Additional Configuration Information File

• Preparing the Mapping File

• Preparing the Directory Integration Profile

• Example: Synchronizing a Relational Database Table to Oracle Internet Directory

Preparing the Additional Configuration Information File

During synchronization from a relational database to Oracle Internet Directory, the additional configuration information file governs the retrieval of data from the database. It provides the Oracle directory integration and provisioning server with the following information:

• The SELECT statement to execute

• Either the attribute(s) or the database column(s) to be used in incremental synchronization. Generally, this is either an attribute that contains a timestamp or a change sequence number that the next SQL statement should use to retrieve incremental data.

To configure this file, use the sample file DBReader.cfg.master in the $ORACLE_HOME/ldap/odi/samples/ directory, and edit it to your specifications.

Formatting the Additional Configuration Information File

It is very important to follow the correct format of this file. The various sections are divided using TAG names. Every TAG section has a list of parameters and their respective values. The general layout is as follows.

[TAG]
PARAMETER1: value
PARAMETER2: value

[TAG]
PARAMETER1: value
PARAMETER2: value\
VALUE continuation\
value continuation\
end of value continuation

[TAG]
PARAMETER1: value
PARAMETER2: value\
end of value continuation

For example, following this format, the DBReader.cfg.master file looks like this:

[DBQUERY]
SELECT: SELECT\

EMPNO EmpNum,\
ENAME,\
REPLACE(EMAIL),'@ACME.COM','') UID,\
EMAIL,\
TELEPHONE,\
TO_CHAR(LAST_UPDATE_DATE,'YYYYMMDDHH24MISS') Modified_Date\

FROM\

EMPLOYEE\

WHERE\

LAST_UPDATE_DATE>TO_DATE (:Modified_Date,'YYYYMMDDHH24MISS')\

ORDER BY\
LAST_UPDATE_DATE

[SYNC-PARAMS]
CHANGEKEYATTRS: Modified_Date

Note that the entire SELECT statement is put as a value in the parameter SELECT in the section represented by the TAG DBQUERY. Because it is a lengthy value, the value continuation character is put as the last character in every line until the SELECT statement ends.

The CHANGEKEYATTRS parameter value is the name of the column(s) to be used while doing incremental synchronization. The value(s) of these column(s) is always stored in the orclOdipLastAppliedChgNum attribute of the profile. Every time the SELECT statement is executed, the current value(s) of this attribute are put into the SQL statement accordingly. This ensures that the data is always retrieved incrementally.

If there are multiple column names in the CHANGEKEYATTRS—for example, column1:column2—then the value in the orclOdipLastAppliedChgNum attribute of the profile is stored as value1~value2 and so on, with value1 corresponding to column1 and value2 to column2.

Column names are retrieved into Directory Integration and Provisioning as attribute value pairs and subsequently mapped into LDAP attribute values according to set mapping rules. For this reason, all columns names retrieved in the SELECT statement must be simple names rather than expressions. For example, you can have the expression REPLACE(EMAIL),'@ACME.COM','') but it retrieves the expression value as UID.

In this example, the Modified_Date is the key for incremental synchronization. Because it is a date, it must be represented in a string format.

When the profile is created, the orclOdipLastAppliedChgNum attribute must be set to some value. All changes after this date—that is, rows in the table with LAST_UPDATE_DATE greater than this value— are retrieved. For example, if the orclOdipLastAppliedChgNum attribute is set to 20000101000000, then all employee changes since January 1, 2000 are retrieved.

Because of the ORDER BY clause, all the database rows returned are in the order of LAST_UPDATE_DATE—that is, the changes retrieved and applied to the directory are in chronological order. Once the last change is retrieved and applied:

1. The orclOdipLastAppliedChgNum attribute value is set to the Modified_Date from the last row retrieved.

2. The profile is updated.

Whenever the Directory Integration and Provisioning executes the profile again, it uses the previously stored value.

Preparing the Mapping File

To configure the mapping rules, follow the instructions in "Mapping Rules and Formats".

Preparing the Directory Integration Profile

You can create the directory integration profile by using the Oracle Directory Integration and Provisioning Server Administration tool or the Directory Integration and Provisioning Assistant. If you use the Oracle Directory Integration and Provisioning Server Administration tool, then you must upload the additional configuration information file and the mapping file by using the Directory Integration and Provisioning Assistant.

To configure the directory integration profile, follow the general instructions in "Registration of Connectors into Oracle Directory Integration and Provisioning", but with these specific instructions in mind:

• Do not set a value for the Agent Execution Command (orclodipAgentExeCommand) attribute.

• Set the Interface Type (orclodipDataInterfaceType) attribute to DB.

  
  

  See Also: "The Directory Integration and Provisioning Assistant (dipassistant) Syntax"

  
  

Example: Synchronizing a Relational Database Table to Oracle Internet Directory

This section demonstrates how to synchronize a relational database table to Oracle Internet Directory. It contains these topics:

• Configuring the Additional Configuration Information File

• Configuring the Mapping File

• Configuring the Directory Integration Profile

• Uploading the Additional Configuration Information File

• Uploading the Mapping File

• The Synchronization Process

• Observations on the Example

In this example, the following relational database table containing employee data is synchronized with Oracle Internet Directory.

Table 9-1 Employee Table

EMPNO	ENAME	LAST_UPDATE_DATE	EMAIL	TELEPHONE
98357	JOHN DOE	2-JAN-2000	[e-mail]	435-324-3455
98360	ROGER BECK	3-JUL-2001	[e-mail]	435-324-3600
98365	JIMMY WONG	4-MAR-2001	[e-mail]	435-324-2390
98370	GEORGE MICHAEL	6-FEB-2002	[e-mail]	435-324-9232

You can find a sample profile for this example in the directory $ORACLE_HOME/ldap/odi/samples. Also present there are the sample configuration and mapping files. In this example:

• The name of the table is Employee

• The Profile Name is TESTDBIMPORT.

• The employee number (EMPNO) is used to JOIN a database record with a directory entry. It is specified in the OID Matching Filter (orclOdipOIDMatchingFilter) attribute described in Table B-1.

• This table is present in the testsync/testsyncpwd schema in a database. The database is located on the host machine.acme.com, the database listener port is 1526 and the SID is iasdb. The database URL is machine.acme.com:1526:iasdb.

• Appropriate read/write permissions have been given explicitly to this profile, namely, orclodipagentname=testdbimport, cn=subscriber profile, cn=changelog subscriber, cn=oracle internet directory

• The profile is created in configuration set 1.

Configuring the Additional Configuration Information File

This example uses the same Additional Configuration Information file described earlier in "Preparing the Additional Configuration Information File".

Configuring the Mapping File

The mapping file for this example contains the following:

DomainRules
NONLDAP:dc=testdbsync,dc=com:uid=%,dc=testdbsync,dc=com
AttributeRules
ename: : : :cn: :person
ename : : : :sn: :person
uid : : : :uid: :inetOrgperson:
EMail: : : :mail: :inetOrgperson
Telephone: : : :telephonenumber: :inetOrgperson
empnum: : : :employeenumber: :inetOrgperson

This mapping file specifies the following:

• Directory entries are created as uid=%,dc=testdbsync,dc=com. The % is a placeholder for the actual value of uid. The uid must be present in the mapping rules so that it has a value after the mapping. Otherwise the DN construction fails.

• Both the cn and sn attributes are to have the same value as ename.

• The uid element must have the value of the EMail prefix, which is the element of the e-mail address prior to the '@' character.

• empnum becomes employeenumber in the directory entry.

• telephone becomes telephone number in the directory entry.

Configuring the Directory Integration Profile

The directory integration profile for this example contains the attribute values as described in Table 9-2. A sample integration profile with these values populated and the corresponding mapping and configuration files are available in $ORACLE_HOME/ldap/odi/samples directory. You can create the profile by running the Directory Integration and Provisioning Assistant in the createprofile mode and specifying the file as the argument. Alternatively, you can create the profile by using the Oracle Directory Integration and Provisioning Server Administration tool.

See Also: "The Directory Integration and Provisioning Assistant (dipassistant) Syntax" "Creating a Profile by Using the Oracle Directory Integration and Provisioning Server Administration Tool" for instructions on creating a profile by using the Oracle Directory Integration and Provisioning Server Administration tool

Table 9-2 Directory Integration Profile for TESTDBIMPORT

Attribute	Value
Profile Name (orclOdipAgentName)	TESTDBIMPORT
Synchronization Mode (orclOdipSynchronizationMode)	IMPORT
Professoriats (orclOdipAgentControl)	ENABLE
Agent Execution Command (orclodipAgentExeCommand)	null
Additional Config Info (orclOdipAgentConfigInfo)	As shown in the preceding file. Needs to be uploaded
Connected Directory Account (orclOdipConDirAccessAccount)	testdbsync
Connected Directory Account Password (orclOdipConDirAccessPassword)	testdbsyncpwd
Connected Directory URL (orclOdipConDirURL)	machine.acme.com:1526:iasdb
Interface Type (orclodipDataInterfaceType)	DB
Mapping File:	To be uploaded from a file
OID Matching Filter (orclOdipOIDMatchingFilter)	employeenumber This means that employeenumber is used to search the directory while looking for a match. If a match is found, then the directory entry is modified. Otherwise, a new entry is created. This is necessary to ensure that the orclOdipOIDMatchingFilter attribute is unique in the database also. Once a database row is retrieved, the Oracle directory integration and provisioning server searches the directory for that employeenumber in the domain dc=testdbsync,dc=com according to the domain rules. If it gets a match, it updates that entry with the latest values of the columns in the row retrieved. If it does not get a match, it creates a new entry in the directory with all the attributes from the column values.
Last Applied Change Number (orclodipConDirLastAppliedChgNum)	20000101000000 This means that the first time the profile executes, it retrieves and synchronizes all four rows. Subsequently, it retrieves rows only when the LAST_UPDATE_DATE column in the table is updated to the time last modified.

Uploading the Additional Configuration Information File

Use the Directory Integration and Provisioning Assistant to upload the additional configuration information file, as follows:

$ORACLE_HOME/bin/dipassistant modifyprofile [-h hostName] [-p port] 
[-D bindDn] [-w password] -profile profName 
odip.profile.mapfile=absolute path name of configuration file

Uploading the Mapping File

Use the Directory Integration and Provisioning Assistant to upload the mapping file, as follows:

$ORACLE_HOME/bin/dipassistant modifyprofile [-h hostName] [-p port]
[-D bindDn] [-w password] -profile profName 
odip.profile.mapfile=absolute path name of mapping file

The Synchronization Process

In this example, the sequence of steps in the synchronization process is:

1. The Oracle directory integration and provisioning server starts a new profile thread for the TESTDBIMPORT profile every time the value specified in the scheduling interval (orclOdipSchedulingInterval) attribute expires.

2. The profile thread reads the additional configuration information to get the SQL to execute, and then runs the SQL.

3. For every row retrieved from the database, the mapping rules are applied to the record and LDAP attributes are created.

4. Depending on the OID Matching Filter (orclOdipOIDMatchingFilter) attribute, the directory integration and provisioning server determines whether a matching entry exists in Oracle Internet Directory or not. If it exists, then it is updated. If not, then a new entry is created. After the directory operation, the last applied change number (orclodipConDirLastAppliedChgNum) attribute is updated.

Observations on the Example

When a row is retrieved from the database, it is in the following form:

EmpNum: 98357
EName: JOHN DOE
UID: JOHN.DOE
EMAIL: [e-mail]
TELEPHONE: [phone]
Modified_Date: 20000102000000

After the mapping is performed on this record, the output is in the following form:

dn: uid=john.doe,dc=testdbsync,dc=com
uid: JOHN.DOE
cn: JOHN DOE 
sn: JOHN DOE 
mail: [e-mail]
employeenumber: 98357
telephonenumber: 435-324-3455
objectclass: person
objectclass: inetorgperson

A subtree search is made in the directory with the filter employeenumber=98357 under the domain dc=testdbsync,dc=com. If the search yields an existing entry, then that entry is updated. Otherwise, a new entry is created. Because the OID Matching Filter (orclOdipOIDMatchingFilter) attribute is set to employeenumber, every database record retrieved must have that column. In this case, it is EmpNum as it maps to employeenumber.

Any other attributes in the mapping file that are not in the data retrieved by the SQL are ignored—for example, the attribute birthday.

After the profile thread processes all the change records from the SQL, it updates the directory with correct values for these attributes:

• Last Applied Change Number (orclodipConDirLastAppliedChgNum)

• Last Execution Time (orclOdipLastExecutionTime)

• Last Successful Execution Time (orclOdipLastSuccessfulExecutionTime)