P6 EPPM Manual Installation Guide (Oracle Database)

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P6 EPPM Manual Installation Guide (Oracle Database)

P6 EPPM Manual Installation Guide (Oracle Database)

Contents

Oracle Database Manual Configuration Overview ,,★★5

Oracle Database Installation ,,★★6

Creating the Database Structure for Oracle and Loading Application Data ,,★★7

Creating the P6 EPPM Database Structure for Oracle ,,★★7

Copying the Script Files to a Local Drive ,,★★7

Grant Privileges to the SYSTEM User ,,★★8

Creating the Database Tablespaces for Oracle ,,★★9

Creating Users and Tables for Oracle ,,★★10

Installing Sample Data and Creating Your P6 EPPM Admin Superuser Password

for Oracle ,,★★11

Creating Remaining Database Objects for Oracle ,,★★13

Dropping P6 EPPM Database Objects for Oracle ,,★★14

Changing the Database Base Currency ,,★★14

The Base Currency ,,★★15

Reviewing Currency Choices ,,★★15

Changing the Base Currency ,,★★15

Private Database Credentials for P6 EPPM ,,★★16

Resetting Private Database Passwords ,,★★16

Adding Private Database Logins for P6 EPPM ,,★★17

Modifying Private Database Logins for P6 EPPM ,,★★18

Deleting Private Database Logins for P6 EPPM ,,★★19

Database Administration ,,★★20

Implementing Transparent Data Encryption on the P6 EPPM Database ,,★★20

Background Processes and Clean Up in P6 EPPM ,,★★21

PX Tables Clean Up Procedure ,,★★22

RDBMS Scheduler Configuration ,,★★22

Database Settings Table ,,★★23

Reading Setting Values ,,★★24

Using Code to Read Setting Values for Oracle ,,★★24

Using Code to Read Setting Values for Microsoft SQL Server ,,★★24

Writing Setting Values ,,★★25

Using Code to Write Setting Values for Oracle ,,★★25

Using Code to Write Setting Values for Microsoft SQL Server ,,★★25

Tracking Background Job Execution ,,★★26

High Level Status Settings ,,★★26

The BGPLOG Table,,★★27

SYMON (System Monitor) Procedures ,,★★28

OBSPROJ_PROCESS_QUEUE Procedure ,,★★29 ●●●

USESSION_CLEANUP_EXPIRED Procedure ,,★★30

Tracking Concurrent Usage of P6 EPPM ,,★★32

DAMON (Data Monitor) Procedures ,,★★33

BGPLOG_CLEANUP Procedure ,,★★33

REFRDEL_CLEANUP Procedure ,,★★34

REFRDEL Bypass Procedure ,,★★35

CLEANUP_PRMQUEUE Procedure ,,★★35

USESSION_CLEAR_LOGICAL_DELETES Procedure ,,★★36

CLEANUP_LOGICAL_DELETES Procedure ,,★★37

PRMAUDIT_CLEANUP Procedure ,,★★38

CLEANUP_USESSAUD Procedure ,,★★39

USER_DEFINED_BACKGROUND Procedure ,,★★41

Oracle Database Performance ,,★★41

Safe Deletes ,,★★41

Turning Off Safe Deletes ,,★★42

PRMAUDIT Auditing ,,★★42

Auditing Level Configuration ,,★★43

Simple Configuration ,,★★43

Detailed Configuration ,,★★44

Auditing Status ,,★★44

Options Setting ,,★★44

SETTINGS_WRITE_STRING Procedure ,,★★46

The Audit Table ,,★★47

Session Auditing ,,★★48

Column Audit Data ,,★★48

Using the Data Pump Utility ,,★★49

Running a Schema Validation on the Database ,,★★50

Running the Data Pump Utility Using the Wizard ,,★★51

Running the Data Pump Utility From the Command Line ,,★★52

Installing P6 EPPM Applications ,,★★53

For More Information ,,★★55

Where to Get Documentation ,,★★55

Documentation Accessibility ,,★★55

Where to Get Training ,,★★55

Where to Get Support ,,★★56

Legal Notices ,,★★58

●●●

Oracle Database Manual Configuration Overview

The P6 EPPM database stores P6 EPPM data used by the P6 EPPM applications.

The database administrator (DBA) should perform the steps in this chapter. You must install the

database server before you can create the database. See the P6 EPPM Planning and

Implementation Guide for details on product versions P6 EPPM supports. See the P6 EPPM

Installation and Configuration to use a wizard that automatically creates the database structures

and loads the data.

P6 EPPM includes an encryption algorithm that provides enhanced security for private database

logins; however, when you manually configure your database, the database does not

automatically enforce the encryption algorithm. If you manually configure your database, Oracle

recommends that you use this encryption algorithm. To do so, you must reset the private database

login. See Resetting Private Database Passwords (on page 16) for instructions. If you

automatically configure your database, you do not need to configure the encryption algorithm.

User logins and passwords are not affected.

User Name and Password Tips

. P6 EPPM does not support passwords with multi-byte characters.

. For security reasons, Oracle strongly recommends that you replace the default database

users‘ (admuser, privuser, pubuser, bgjobuser, and PxRptUser) passwords immediately after

a manual database installation or an upgrade from P6 version 7.0 and earlier. Do not use

special characters in the database name, privileged user, public user, or PX Reporting user

name for example: { } [ ] : ; < > , . ? ! @ # $ % ^ & * ( ) - _ | / \ ~ `

. Oracle recommends using strong passwords. Strong passwords in P6 EPPM contain between

8 and 20 characters and at least one numeric and one alpha character. To further strengthen

the password, use a mixture of upper and lower case letters.

. See Modifying Private Database Logins for P6 EPPM (on page 18) for instructions on how

to replace the private database login. For all other database user names and passwords, use

the tools included with the database.

. For security reasons, Oracle strongly recommends that you replace the default Admin

Superuser (admin) immediately after a manual database installation or an upgrade from P6

version 7.0 and earlier. See information on the default Admin Superuser in the P6 EPPM

Application Administration Guide for guidelines on this process.

Security Tips

. To configure the Oracle database server for SSL, please see the P6 EPPM Security Guide

included with the Oracle Database Server Documentation for configuring the Oracle Server

and Oracle Client(s) for SSL.

●●●

In This Section

Oracle Database Installation ,,★★6

Creating the Database Structure for Oracle and Loading Application Data ,,★★7

Changing the Database Base Currency ,,★★14

Private Database Credentials for P6 EPPM ,,★★16

Oracle Database Installation

You can use an Oracle database on your database server for P6 EPPM installations. You must

install the database server before you can create the P6 EPPM database.

Notes:

. When you attempt to create a database using Oracle Database 12c,

the option to create a pluggable database will be enabled by default. If

you do not want to create a container database, deselect the Create

As Container Database check box during the database creation

process. If you create a container database, you must also create a

pluggable database on which to install your P6 EPPM instance.

. When using an Oracle database, you must install Oracle Multimedia,

along with these supporting components: Oracle JVM, Oracle XML

DB (XDB), and XML Developer‘s Kit (XDK). Unless you specify

otherwise, all these components automatically get installed with the

latest versions of an Oracle database (11g and later). If you chose not

to install these components, you will need to install them before you

install P6 EPPM. See the Oracle Multimedia‘s User‘s Guide on the

Oracle Technology Network (OTN) for information on how to install

these components.

●●●

Creating the Database Structure for Oracle and Loading Application Data

The Oracle database administrator (DBA) creates the P6 EPPM database, then runs P6 EPPM

SQL scripts, which create each database’s structure (tables, indexes, relationships, etc.).

Notes:

. Oracle must be run in Dedicated Mode (rather than MTS mode).

. If you need to use the Euro symbol in any Western European

language, you must use codepage WE8MSWIN1252 or UTF8. Please

note, if you change the NLS_LENGTH_SEMANTICS parameter from

BYTE to CHAR, you will not affect the software. Oracle recommends

using CHAR if using UTF8 because some characters are two or three

bytes.

These instructions assume you are an Oracle DBA or are familiar with administering Oracle

databases. They also assume you have set up an Oracle server instance and configured your

network. You must complete the steps in the order specified. If you have any questions about the

manual setup process, please contact Oracle Global Customer Support before proceeding.

You can also use a wizard that automatically creates the database structures and loads the data

for you. For more information, see the P6 EPPM Installation and Configuration Guide.

Oracle recommends that you use SQL Plus to run scripts referenced in the following instructions.

Creating the P6 EPPM Database Structure for Oracle

Complete the following steps to create the P6 EPPM Oracle database structure.

Copying the Script Files to a Local Drive

To copy the script files:

1) Copy the \database folder to a local drive from the physical media or download.

●●●

Grant Privileges to the SYSTEM User

Before installing P6 EPPM, execute the following steps:

1) Navigate to the following location, open the designated script in a text editor, and modify the

schema user reference to match your actual schema user name:

\scripts\install\PM_<release level>\manual_script_before_install.sql

You must apply grant options to the SYSTEM schema user or a custom user associated

with the Oracle DBA role. If you plan to use a custom schema user, other than SYSTEM, to

execute steps which require a DBA role, then you must update the references to SYSTEM

in the script with the new custom schema user associated with the DBA role.

2) From the command line, execute: sqlplus sys/[email protected]<db_tns_names_entry> as

sysdba

3) Go to p6suite\database\scripts\install\PM_<release_level>, and execute

manual_script_before_install.sql.

This script grants SELECT and EXECUTE privileges with grant option to SYSTEM, or a

custom DBA username if you prefer to use one, for the following sys objects:

SELECT

. sys.DBA_VIEWS

EXECUTE

. sys.DBMS_DBMS_REPUTIL

. sys.DBMS_DBMS_LOB

. sys.DBMS_SQL

. sys.DBMS_JOB

. sys.DBMS_RANDOM

. sys.V_$TRANSACTION

Note: For more information about the listed sys objects, refer to the Oracle

Database documentation.

●●●

Creating the Database Tablespaces for Oracle

To create database tablespaces:

1) Execute the following steps:

a. From the command line, execute: sqlplus

<system>/[email protected]<db_tns_names_entry>:

b. Go to \database\scripts\install\PM_<release_level> and execute the orpm_init_db.sql

script.

This script creates the following tablespaces:

. PMDB_DAT1

. PMDB_NDX1

. PMDB_LOB1

. PMDB_PX_DAT1

If you want to change the names of the tablespaces that are listed above, you must modify

the orpm_init_db.sql script before you execute it.

Notes:

. Do not use special characters in the database name, privileged user,

public user, or PX reporting user name, for example: { } [ ] : ; < > , . ? !

@ # $ % ^ & * ( ) - _ | / \ ~ `

. Instead of running the orpm_init_db.sql script, you can manually

create a database with system, temporary, and undo tablespaces.

Oracle recommends that you create a database with a 500 MB

temporary tablespace and a 500 MB undo tablespace. Make sure that

the Oracle client can connect to the database. Refer to your Oracle

database documentation if you are unfamiliar with this process.

●●●

Creating Users and Tables for Oracle

The scripts in this task are located in:

\database\scripts\install\PM_<release_level>

To create users and tables:

1) Execute the following steps:

a. From the command line, execute: sqlplus

<system>/[email protected]<db_tns_names_entry>

b. Execute the orpm_create_users.sql script.

Running the orpm_create_users.sql script automatically creates database user names:

admuser, privuser, pubuser, pxrptuser, and bgjobuser. If you want to create non-default

usernames, you must first open the script in a text editor and then replace the default

references before you run the script.

Running the orpm_create_users.sql script references the following default tablespace

names: PMDB_DAT1, PMDB_NDX1, PMDB_LOB1, and PMDB_PX_DAT1. If you created

the tablespaces using non-default names, you must first open the script in a text editor and

replace the default references before you run the script.

Note: Do not use special characters in the database name, privileged

user, public user, or PX reporting user name, for example: { } [ ] : ; < > , . ?

! @ # $ % ^ & * ( ) - _ | / \ ~ `

c. Execute the orpm_grant_privileges.sql script.

Running the orpm_grant_privileges.sql script references the following database user

names: admuser, privuser, pubuser, pxrptuser, and bgjobuser. If you want to create

non-default usernames, you must first open the script in a text editor and then replace the

default references prior to running the script.

2) Execute the following steps:

a. From the command line, execute: sqlplus

<admuser>/[email protected]<db_tns_names_entry>

b. Execute the orpm_tables.sql script.

Running the orpm_tables.sql script references the following default user names: privuser,

pubuser, and pxrptuser. If you created non-default user names, you must first open the

script in a text editor and replace the default references before you run the script.

Running the orpm_tables.sql script references the following default tablespace names:

PMDB_DAT1, PMDB_LOB1, and PMDB_PX_DAT1. If you created the tablespaces using

non-default names, you must first open the script in a text editor and replace the default

references before you run the script.

●●●

Installing Sample Data and Creating Your P6 EPPM Admin Superuser Password for Oracle

To install sample data:

1) Open command prompt (if Windows) or terminal (if UNIX) and connect to your database using

the following command:

sqlplus sys/[email protected] as sysdba

2) Execute the following commands in the same window:

noaudit policy ORA_SECURECONFIG

noaudit policy ORA_LOGON FAILURES

3) Close the window.

4) Open a fresh command prompt (if windows) or terminal (if UNIX) and then change your

directory to the location of the rundataloader.bat (.sh) file, which is on the root of the database

folder by default.

5) Execute a statement similar to one of the following:

. Use this command if you want to load sample data into a non-production environment.

If you are using Windows

rundataloader.bat sample:pmdb_mk.zip

<admuser>@oracle:<host>:<port>:<SID_name>

rundataloader.bat sample:pmdb_mk.zip

<admuser>/<admuser_password>@oracle:<host>:<port>/<service_name>

If you are using Unix

./rundataloader.sh sample:pmdb_mk.zip

[email protected]:host:port:<SID_name>

./rundataloader.bat sample:pmdb_mk.zip

<admuser>/<admuser_password>@oracle:<host>:<port>/<service_name>

. Use this command if you do not want to load sample data. Empty data is loaded in a secure

state and includes only the basic information needed to run the P6 EPPM database.

If you are using Windows

rundataloader.bat sample:pmdb_mk_empty.zip

[email protected]:host:port:<SID_name>

rundataloader.bat sample:pmdb_mk_empty.zip

<admuser>/<admuser_password>@oracle:<host>:<port>/<service_name>

If you are using Unix

./rundataloader.sh sample:pmdb_mk_empty.zip

<admuser>@oracle:host:port:<SID_name>

./rundataloader.bat sample:pmdb_mk_empty.zip

<admuser>/<admuser_password>@oracle:<host>:<port>/<service_name>

●●●

Note:

. For the connection strings above: <admuser> is the database admin

user that you created, <admuser_password> is the password for the

database admin user, <host> is the server machine name or IP

address where Oracle is installed, <port> is the port number that

Oracle is using (the default is 1521), <SID_name> is the database SID

(for example, PMDB), and <service_name> is the database service

name (for example, orcl.us.oracle.com)

. If you use the connection string that is associated with a service name

and do not include <admuser_password> in your connection string,

you will experience a Java error and no data will be loaded into your

environment.

6) Do the following:

a. In the "WARNING:This operation will destroy existing data in the database: Do you wish to

continue? (Y or N)" prompt, enter: Y.

b. In the "Password for admuser:" prompt, enter the the password of your admuser or custom

administrative user that you created.

c. In the "Please select a password for the P6 ‘admin‘ SuperUser account" prompt, enter or

verify your superuser password.

●●●

Creating Remaining Database Objects for Oracle

To create the remaining database objects:

Note: After each step, log out of the database.

1) Execute the following steps:

a. From the command line, execute: sqlplus

<admuser>/[email protected]<db_tns_names_entry>

b. Go to \scripts\install\PM_<release_level> and execute the orpm_admuser.sql

script.

Running the orpm_admuser.sql script references the following default user names:

admuser, privuser, and pxrptuser. If you created non-default user names, you must open

the script in a text editor and then replace the default references before you run the script.

Running the orpm_admuser.sql script references the following default tablespace names:

PMDB_NDX1 and PMDB_PX_DAT1. If you created the tablespaces using non-default

names, you must open the script in a text editor and then replace the default references

before you run the script

2) Execute the following steps:

a. From the command line, execute: sqlplus

<privuser>/[email protected]<db_tns_names_entry>

b. Go to \scripts\source\PM_<release_level> and execute the orpm_privuser.sql

script.

Running the orpm_privuser.sql script references the admuser name. If you created

non-default user names, you must open the script in a text editor and then replace the

default references before you run the script.

3) Execute the following steps:

a. From the command line, execute: sqlplus

<pubuser>/[email protected]<db_tns_names_entry>

b. Go to \scripts\source\PM_<release_level> and execute the orpm_pubuser.sql

script.

Running the orpm_pubuser.sql script references the admuser name. If you created

non-default user names, you must open the script in a text editor and then replace the

default references before you run the script.

4) Execute the following steps:

a. From the command line, execute: sqlplus

<pxrptuser>/[email protected]<db_tns_names_entry>

b. Go to \scripts\source\PM_<release_level> and execute the orpm_pxrptuser.sql

script.

Running the orpm_pxrptuser.sql script references the admuser name. If you created

non-default user names, you must open the script in a text editor and then replace the

default references before you run the script.

5) Execute the following steps:

●●●

a. From the command line, execute: sqlplus

<bgjobuser>/[email protected]<db_tns_names_entry>

b. Go to \scripts\source\PM_<release_level> and execute the orpm_bguser.sql script

Running the orpm_bguser.sql script references the admuser name. If you created

non-default user names, you must open the script in a text editor and then replace the

default references before you run the script.

6) Execute the following steps:

a. From the command line, execute: sqlplus

<system>/[email protected]<db_tns_names_entry>

b. Go to \scripts\install\PM_<release_level> and execute the orpm_reset_priv.sql

script.

Running the orpm_reset_priv.sql script references the following default user names:

admuser, pxrptuser, and bgjobuser. If you created non-default user names, you must open

the script in a text editor and then replace the default references before you run the script.

Running the orpm_reset_priv.sql script references the following default tablespace

names: PMDB_DAT1, PMDB_NDX1, PMDB_LOB1, and PMDB_PX_DAT1. If you

created the tablespaces using non-default names, you must open the script in a text editor

and then replace the default references prior to running the script.

7) Do the following:

a. Log into the databaselogins.bat (on Windows) or databaselogins.sh (on Unix) database

as admuser, or use your custom administrative user name if you created one.

b. Update the privuser name and password to match what you used when you created your

user names and passwords.

Dropping P6 EPPM Database Objects for Oracle

If you make a mistake or want to recreate the database objects for the P6 EPPM database:

1) Go to \database\scripts\install\PM_<release_level> and execute the orpm_drop_users.sql

script. This will drop admuser, privuser, pubuser, bgjobuser, and PxRptUser and their objects.

2) Start over at Creating Users and Tables for Oracle (on page 10).

Changing the Database Base Currency

Caution: You cannot change the base currency once projects begin.

After manually creating and configuring the P6 EPPM database, you must change the base

currency if you do not want the databases to use US dollars ($) as the base currency.

●●●

The Base Currency

The base currency is the monetary unit used to store cost data for all projects in the database and

is controlled by a global administrative setting. The default base currency for P6 EPPM is US

dollars ($). The view currency is the monetary unit used to display cost data in P6 EPPM and is

controlled by a user preference.

The exchange rate for the base currency is always 1.0. When a user selects a different currency

than the base currency to view cost data, the base currency value is multiplied times the current

exchange rate for the view currency to calculate the values displayed in cost and price fields.

For example, if the base currency is US Dollars, the view currency is Euros, and the exchange rate

for Euros is $1 = €0.75, a value of $10 stored in the database is displayed as €7.5 in cost and price

fields. Similarly, if you enter €7.5 in a cost or price field, it is stored in the database as $10.

When data is displayed in a view currency that is different than the base currency, some cost and

price values can vary slightly (e.g., due to rounding). As long as the correct base currency is

selected during database installation, a user can view completely accurate cost and price data by

changing the view currency to match the base currency.

Reviewing Currency Choices

To change the base currency you need to edit and run the P6 EPPM script provided. By default,

US dollars is the base currency, and USD is the short name used in the script. To know which

short name to use, review the list of available short names for P6 EPPM by running the following

query on the P6 EPPM database:

select curr_type, curr_short_name from currtype;

Changing the Base Currency

To change the base currency:

1) On the P6 EPPM physical media or download:

a. Browse to \Database\scripts\common.

b. Copy this script to a local drive:

For Oracle: or_set_currency.sql

2) If you copied the script from the physical media, turn off the script‘s read-only attribute.

Since files on physical media are read-only, this attribute turns on when you copy a file from a

CD or DVD.

a. In Windows Explorer, right-click the file.

b. Choose Properties.

c. Clear the Read-Only option.

3) Open the script for editing and locate the line containing v_new_base_currency: = ‘USD’

4) Replace USD with the currency short name of your choice.

5) Save your changes and run the modified script.

●●●

Private Database Credentials for P6 EPPM

The P6 server and P6 Professional components obtain their run-time database connection

credentials from a credential configuration table in the P6 EPPM database. The P6 run-time

database credentials (known as privuser or P6 private database login) are stored in an encrypted

format in this special P6 configuration table. Any time that you change or rotate the privuser

password credentials in your Oracle or MS SQL Server database, you must re-synchronize the

stored credentials in the P6 credential table by using the Database Login tool.

Because encryption algorithms are often enhanced in newer releases, Oracle highly recommends

that you reset these stored privuser credentials when you perform a major version upgrade of P6

EPPM. By resetting the stored credentials, the new encryption algorithm can be applied to other

stored credentials (for example, pubuser) in the P6 EPPM credential table. For information about

resetting private database passwords, see Resetting Private Database Passwords (on page

16).

Note: This tool does not reset database user logins or passwords.

Administrators should use SQL Developer or other DBA consoles to set or

reset database user passwords.

Resetting Private Database Passwords

Complete the following steps to reset private database passwords to use the new encryption

algorithm:

1) Go to P6 EPPM <release_level>\database and run databaselogins.bat (with Windows)

databaselogins.sh (with UNIX or Linux).

2) On the Database Connection dialog box:

a. Select the database.

b. Type the user name and password of a privileged database user (for example, privuser).

This login should have administrative rights on the database.

c. Enter the host address, host port, and database/instance name specific to your installation.

The Port field displays the default port for the database type you selected.

d. Click Next.

3) On the Private Database Logins dialog box:

a. Select the private database user name that you wish to reset.

b. Highlight the password and change it (or simply re-enter the existing password).

c. Click the Update Password button.

Note: To reverse a change, click Undo.

d. Click Save.

e. Click OK to exit the Database Logins tool.

●●●

Adding Private Database Logins for P6 EPPM

Complete the following steps to add private database logins for P6 EPPM:

1) Go to P6 EPPM <release_level>\database and run databaselogins.bat (with Windows)

databaselogins.sh (with UNIX or Linux).

2) On the Database Connection dialog box:

a. Select the database.

b. Type the user name and password of a privileged database user (for example, privuser).

This login should have administrative rights on the database.

c. Enter the host address, host port, and database/instance name specific to your installation.

The Port field displays the default port for the database type you selected.

d. Click Next.

3) On the Private Database Logins dialog box:

a. Click Add.

b. Enter a user name.

c. Enter a password.

Note: To reverse a change, click Undo. Undo will reverse any changes

made during the current session.

d. Click Save.

e. Click OK to exit.

●●●

Modifying Private Database Logins for P6 EPPM

Complete the following steps to modify private database logins:

1) Go to P6 EPPM <release_level>\database and run databaselogins.bat (with Windows)

databaselogins.sh (with UNIX or Linux).

2) On the Database Connection dialog box:

a. Select the database.

b. Type the user name and password of a privileged database user (for example, privuser).

This login should have administrative rights on the database.

c. Enter the host address, host port, and database/instance name specific to your installation.

The Port field displays the default port for the database type you selected.

d. Click Next.

3) On the Private Database Logins dialog box:

a. Select the private database user name that you wish to modify.

b. Enter a new user name.

c. Highlight the password, and change it.

d. Click the Update Password button.

Note: To reverse a change, click Undo. Undo will reverse any changes

made during the current session.

e. Click Save.

f. Click OK to exit the Database Logins tool.

●●●

Deleting Private Database Logins for P6 EPPM

Complee the following steps to delete private database logins for P6 EPPM:

1) Go to P6 EPPM <release_level>\database and run databaselogins.bat (with Windows)

databaselogins.sh (with UNIX or Linux).

2) On the Database Connection dialog box:

a. Select the database.

b. Type the user name and password of a privileged database user (for example, privuser).

This login should have administrative rights on the database.

c. Enter the host address, host port, and database/instance name specific to your installation.

The Port field displays the default port for the database type you selected.

d. Click Next.

3) On the Private Database Logins dialog box:

a. Select the private database user name that you wish to remove.

Note: You must have at least one private user name for the P6 EPPM

database at all times.

b. Click Delete.

Note: To reverse a change, click Undo. Undo will reverse any changes

made during the current session.

c. Click Save.

d. Click OK to exit the Database Logins tool.

●●●

Database Administration

Read this chapter to learn how to configure the job scheduler supplied by your RDBMS, how to

optimize performance of your P6 EPPM database, and how to configure the PRMAUDIT feature to

monitor edits, deletions, and additions to the databases.

In This Section

Implementing Transparent Data Encryption on the P6 EPPM Database ,,★★20

Background Processes and Clean Up in P6 EPPM ,,★★21

PX Tables Clean Up Procedure ,,★★22

RDBMS Scheduler Configuration ,,★★22

Database Settings Table ,,★★23

Reading Setting Values ,,★★24

Writing Setting Values ,,★★25

Tracking Background Job Execution ,,★★26

SYMON (System Monitor) Procedures ,,★★28

DAMON (Data Monitor) Procedures ,,★★33

Oracle Database Performance ,,★★41

Safe Deletes ,,★★41

PRMAUDIT Auditing ,,★★42

Using the Data Pump Utility ,,★★49

Implementing Transparent Data Encryption on the P6 EPPM Database

Transparent data encryption (TDE) is an Oracle Advanced Security feature that is used for Oracle

Database encryption. TDE provides strong protection from malicious access to database files by

encrypting data before it is written to storage, decrypting data when being read from storage, and

offering built-in key management.

For more information about TDE, refer to

http://www.oracle.com/technetwork/database/options/advanced-security/index-099011.html.

For TDE implementation instructions, refer to the readme.txt file in the P6 EPPM physical

media or download at database\scripts\common\tde.

●●●

Background Processes and Clean Up in P6 EPPM

Because clean up tasks can be resource intensive and time consuming, in P6 EPPM, these tasks

are initiated by two background jobs that run on the database server using the background job

processes user name:

. SYMON (System Monitor), responsible for running procedures that take less than a few

seconds to complete.

. DAMON (Data Monitor), responsible for running procedures that take longer than a few

seconds to complete.

Both of these jobs are pre-configured with default settings. Since the default settings are optimal

for most environments, you generally do not need to tune them. However, if you need to optimize

your background process further, you can use the background job processes user to change the

settings to tune the behavior of the background jobs for specific environments.

The background process will:

. Update the settings table with a record each time a job runs.

. Update the settings table with a HeartBeatTime record for both the SYMON and DAMON

processes. The background processes regularly refresh the record to indicate that they are

still running.

When you initiate background jobs:

. Execute the stored procedure INITIALIZE_BACKGROUND_PROCS.

. Locate the logs of background process activity in BPLOGS and SETTINGS tables within the

Primavera database.

●●●

PX Tables Clean Up Procedure

To avoid operational problems for P6, PX table entries are not automatically deleted when you

delete data from P6 tables. You can use the following clean up procedure to clear the obsolete

entries in PX tables.

1) Run the CLEAN_PX_DELETE stored procedure to purge obsolete entries in the PX tables:

For Oracle:

BEGIN

CLEAN_PX_DELETE();

END;

Note: You can run this procedure any time you want or you can run it as a

database background job and schedule a specific time for it to run.

2) To delete batch size and max delete from each table in a single run, run the following queries:

Note: You can specify the delete batch size and max delete from each

table in a single run. Delete batch size is the number of rows deleted

before a commit. Max delete is the max number of rows that will be

deleted from a table in a single run. They have default values if you do not

provide your own. They‘re used to avoid resource problems with the P6

operations.

. insert into settings (namespace, setting_name, setting_value) values

(‘PxService.Cleanup‘,‘DeleteMaxSize‘,‘100000‘);

. insert into settings (namespace, setting_name, setting_value) values

(‘PxService.Cleanup‘,‘DeleteBatchSize‘,‘5000‘);

RDBMS Scheduler Configuration

Since background jobs are initiated by the job scheduler supplied by the RDBMS, you need to

ensure that the scheduler for your specific RDBMS is properly configured.

For an Oracle Database: P6 EPPM uses DBMS_SCHEDULER to schedule background jobs in

Oracle. P6 EPPM 15 R2 does not need parameter changes.

●●●

Database Settings Table

Settings Table Overview

The settings table contains name-value pairs that configure the behavior of the background

processes.

Namespace

The namespace component is a dot-notation string representing a formal path to the parameter.

Setting Name

The setting name identifies the name of the setting.

Value

Values in the SETTINGS table are case-sensitive. The value portion of the pair can be:

. String: The string data type is a free text value. The most common string sub-type is interval

which represents an interval of time by combining a numeric portion with a unit portion as

depicted in the table below.

Interval Subtype Table

Unit portion

Example

Meaning

Numeric portion

+

d

‘30d’

Thirty day interval

h

‘2h’

Two hour interval

m

‘10m’

Ten minute interval

s

‘30s’

Thirty second interval

. Numeric: The numeric data type consists of any number.

. Boolean: The Boolean data type can have one of two values: true or false, where zero

represents false and any non-zero number represents true.

. Date: The date data type consists of dates.

Setting Example

The following is an example of a setting:

. Namespace: database.cleanup.Usession

. Setting Name: ExpiredSessionTimeout

. Value: 2h (two hour interval)

●●●

Reading Setting Values

You can configure settings through the Settings API Procedures. These procedures are similar to

registry or INI file procedure calls.

Reading Settings Values

Use the following SETTINGS_READ_* procedures to determine the current value of specific

settings:

. SETTINGS_READ_STRING(ret_val,namespace,settings_name,default)

. SETTINGS_READ_DATE(ret_val,namespace,settings_name,default)

. SETTINGS_READ_NUMBER(ret_val,namespace,settings_name,default)

. SETTINGS_READ_BOOL(ret_val,namespace,settings_name,default)

Using Code to Read Setting Values for Oracle

The following code snippets for the Oracle Database demonstrate how the SETTINGS_READ_*

procedures read the setting values.

To retrieve the value of the KeepInterval setting in Oracle:

1) Use the following code:

SQL> variable vset varchar2(255)

SQL> exec settings_read_string(:vset,‘database.cleanup.Usession‘,

‘ExpiredSessionTimeout‘);

2. The following message should appear:

PL/SQL procedure successfully completed.

SQL> print vset

Using Code to Read Setting Values for Microsoft SQL Server

The following code snippets for the Microsoft SQL Server database demonstrate how the

SETTINGS_READ_* procedures read the setting values.

To retrieve the value of the KeepInterval setting in SQL:

1) Use the following code:

declare @vset varchar(255)

exec settings_read_string @vset

OUTPUT,‘database.cleanup.Usession‘,‘ExpiredSessionTimeout‘

print @vset

2) The following message should appear:

PL/SQL procedure successfully completed.

SQL> print vset

●●●

Writing Setting Values

Use the SETTINGS_WRITE_STRING procedure to set the value of a specific setting:

SETTINGS_WRITE_STRING(new value,namespace,settings_name);

Using Code to Write Setting Values for Oracle

The following code snippets for Oracle Database demonstrate how the

SETTINGS_WRITE_STRING procedure sets the value of the ExpiredSessionTimeout setting to

twelve hours.

To set the value of the ExpiredSessionTimout setting to twelve hours in an Oracle Database:

1) Log into SQL *Plus using privuser as your user name.

2) Run the following statement:

SQL > exec SETTINGS_WRITE_STRING

(‘12h‘,‘database.cleanup.Usession‘,‘ExpiredSessionTimeout‘);

Using Code to Write Setting Values for Microsoft SQL Server

The following code snippets for Microsoft SQL Server databases demonstrate how the

SETTINGS_WRITE_STRING procedure sets the value of the ExpiredSessionTimeout setting to

twelve hours.

To set the value of the ExpiredSessionTimeout setting to twelve hours in a Microsoft SQL Server

database:

1) Open the Query Analyzer/SSMS and connect as privuser.

2) Select the P6 EPPM database, then run the following statement (using 12 hours as an

example):

exec SETTINGS_WRITE_STRING ‘12h‘,‘database.cleanup.Usession‘,

‘ExpiredSessionTimeout‘

●●●

Tracking Background Job Execution

You can track the execution of background jobs by monitoring the high level status settings or by

inspecting the BGPLOG table.

High Level Status Settings

Each time a job runs it will update the SETTINGS table for the setting_name = ‘HeartBeatTime.‘

The job can update this value multiple times during the execution. You can monitor the maximum

difference between this time and the current date to ensure that the job is running promptly. Refer

to the High Level Status Settings table below for information about the HeartBeatTime setting.

High Level Status Settings

Last date and time background job SYMON ran.

Namespace

database.background.Symon

Setting Name

HeartBeatTime

Default Setting

N/A

Last date and time background job DAMON ran.

Namespace

database.background.Damon

Setting Name

HeartBeatTime

Default Setting

N/A

●●●

The BGPLOG Table

You can also track the execution of background jobs by inspecting the BGPLOG table. The

BGPLOG table holds detailed entries from the background processes including informational,

elapsed time, and error entries. Refer to the BGPLOG Table Descriptions for information about

what this table contains.

BGPLOG Table Descriptions

Column

Description

Value

Log_time

Time when background

process made a log entry

Datetime

Source

Program generating log entry

"system_monitor", "data_monitor"

Type

Type of message

INFORMATION, ELAPSED TIME,

ERROR

Description

Message from the

background process

A variable message followed by a

number in parenthesis that represents

the number of rows that processed.

As an example, the message

"Complete BGPLOG (40)" indicates

that forty rows processed.

●●●

SYMON (System Monitor) Procedures

SYMON runs simple P6 EPPM tasks on a quick schedule. By default, the job runs every minute;

the tasks assigned to this job should take only a few seconds to complete on each run. Do not

change the scheduled run time (every minute) for this procedure.

Procedures performed by SYMON

The procedures run by SYMON perform these tasks:

. Processing the PRMQUEUE entries for Project Security by queuing OBSPROJ updates to the

PRMQUEUE table.

. Marking expired USESSION records as logically deleted.

Note: You can manually run queries to assist you with tracking concurrent

usage of P6 EPPM.

●●●

OBSPROJ_PROCESS_QUEUE Procedure

OBSPROJ_PROCESS_QUEUE processes the PRMQUEUE entries for Project Security. It defers

processing of OBSPROJ updates by queuing the updates to the PRMQUEUE table.

Refer to the following table for information about the settings associated with the

OBSPROJ_PROCESS_QUEUE procedure.

OBSPROJ_PROCESS_QUEUE Settings

Setting Description: Maximum project-level queue records to process on each run.

Namespace

database.obsproj.queue

Setting Name

MaxProjectUpdates

Default Setting

1000

Type

Numeric

Setting Description: Maximum EPS-level queue records to process on each run.

Namespace

database.obsproj.queue

Setting Name

MaxEpsUpdate

Default Setting

25

Type

Numeric

Setting Description: Maximum times to re-process a failed entry before marking it as an

error.

Namespace

database.obsproj.queue

Setting Name

MaxRetries

Default Setting

50

Type

Numeric

●●●

USESSION_CLEANUP_EXPIRED Procedure

USESSION_CLEANUP_EXPIRED logically deletes USESSION records that have not updated

their last_active_time based on the Expired Session settings. Marking expired USESSION

records as logically deleted maximizes the number of module access logins that are available.

Since it is not cleaning up the underlying data (physically deleting rows), the task completes

quickly.

Values in the SETTINGS table control the clean up of expired sessions. By default, although the

clean up of expired sessions occurs every two hours, the SETTINGS table does not contain a

value for this setting. Use the SETTINGS_WRITE_STRING (value, namespace, setting) stored

procedure to change the default clean up value.

For example, setting the value to "2d" deletes expired sessions older than two days.

Note: Oracle recommends that you set the ExpiredLongSessionTimeout

sessions to at least one hour longer than your longest job. For example, if

your longest job is a summarizer job that usually takes 12 hours, you

should set the value in the SETTINGS table to at least 13.

Refer to the table below for information about the USESSION_CLEANUP_EXPIRED Settings.

USESSION_CLEANUP_EXPIRED Settings

Setting Description: ExpiredSessionTimeout determines how long an inactive user

session will remain in the records before it is marked deleted. User sessions are created

when a P6 user logs into P6.

Namespace

database.cleanup.Usession

Setting Name

ExpiredSessionTimeout

Default Setting

2h

Type

Interval

Setting Description: ExpiredLongSessionTimeout determines how long a session that is

running a job-like operation (that is still processing) will remain in the records before it is

marked deleted. Job-like operations are processed by job services and some are

performed by logged in P6 users. Operations that are considered job-like are:

. Scheduling

. Leveling

. Apply Actuals

. Update Progress

. Copy/Paste Project

. Create Project from Template

. Maintain Baselines (create new baseline)

. Approve Timesheets

. Summarize

. PX Publish

●●●

. Export

. Import

Namespace

database.cleanup.Usession

Setting Name

ExpiredLongSessionTimeout

Default Setting

12h

Type

Interval

●●●

Tracking Concurrent Usage of P6 EPPM

To track concurrent usage of P6 EPPM, you can run queries against the USESSION and

USESSAUD tables to perform self-audits. See sample queries below.

Note: See DAMON (Data Monitor) Procedures (on page 33) for

information on how to set up the USESSAUD procedure. To ensure

accuracy of these queries, run them before physically deleting remaining

USESSION records and cleaning up the USESSAUD table.

. Against the USESSION table, run the following query to determine how many users are

logged in at a given time:

select count(*) from usession where delete_session_id is null

. Against the USESSION table, run the following query to determine how many users are

logged into a specific P6 EPPM product at a given time:

select count (*) from usession where delete_session_id is null and

app_name=‘P6 EPPM product name‘

where P6 EPPM product name is the application abbreviation.

Note: You can view all available application abbreviations by running the

following query as an administrative database user: select

distinct(db_engine_type) from usereng

. Against the USESSAUD table, run a query similar to the following to determine how many

users logged into P6 EPPM on a specific date during a specified time range. You can alter the

date, time range, and P6 EPPM product as needed. The following example will search for all

users who logged into P6 Professional on February 17, 2010 between 9am and 10am:

For an Oracle database:

select * from usessaud where login_date between to_date(‘17-FEB-10

09:00:00‘,‘DD-MON-YY HH:MI:SS‘) and to_date(‘17-FEB-10

10:00:00‘,‘DD-MON-YY HH:MI:SS‘) and app_name=‘Project Management‘

Tips

See "Counting Users" in the P6 EPPM System Administration Guide for information on counting

users and how to view the total number of licenses assigned for each module.

●●●

DAMON (Data Monitor) Procedures

The second database job is the DAMON data monitor job. The DAMON job runs the majority of the

background processing and is responsible for running background clean up processes required by

the application that can potentially take a relatively long time to run.

Oracle and DAMON

By default, DAMON runs every Saturday. It uses the Oracle DBMS_SCHEDULER package to

schedule the jobs, and an Interval setting controls the schedule and accepts the same parameters

as the DBMS_SCHEDULER interval. For more information, refer to your Oracle database

documentation.

DAMON Procedures

DAMON cleans the:

. BGPLOG table containing the background logs.

. REFRDEL table.

. PRMQUEUE table.

. Remaining USESSION records.

. Logically deleted records.

. PRMAUDIT table.

. USESSION audit table (USESSAUD).

You can also dynamically extend DAMON functionality via the user-defined procedure,

USER_DEFINED_BACKGROUND.

BGPLOG_CLEANUP Procedure

This procedure keeps the BGPLOG table at a reasonable size. The default cleanup interval is 5

days which will result in a table size of about 54,000 records.

Refer to the following table for information about the settings associated with the

BGPLOG_CLEANUP procedure.

BGPLOG_CLEANUP Settings

Setting Description: The oldest records to keep in the BGPLOG table.

Namespace

database.cleanup.BackGroundProcessLog

Setting Name

KeepInterval

Default Setting

5d

Type

Interval

●●●

REFRDEL_CLEANUP Procedure

This procedure deletes records from the REFRDEL table. REFRDEL_CLEANUP runs based on

the frequency of data_monitor_job, which has a default frequency of one week. Alternatively, you

can run REFRDEL_CLEANUP by itself if needed.

Refer to the following table for information about the settings associated with the

REFRDEL_CLEANUP procedure:

REFRDEL_CLEANUP Settings

Setting Description: Identifies the number of days that records are stored in the

REFRDEL table before they can be removed. For example, the default setting keeps the

REFRDEL records from the last five days.

Namespace

database.cleanup.Refrdel

Setting Name

KeepInterval

Default Setting

5d

Type

Interval

Setting Description: Identifies the number of days that are set to be removed from the

REFRDEL table starting with the oldest record in the table.

Namespace

database.cleanup.Refrdel

Setting Name

DaysToDelete

Default Setting

1

Type

Numeric

Setting Description: Determines the intervals of time (in minutes) in which data is

grouped and removed from the REFRDEL table. The number of IntervalSteps is equal to

DaysToDelete (in minutes) divided by IntervalStep.

Namespace

database.cleanup.Refrdel

Setting Name

IntervalStep

Default Setting

15

Type

Numeric

●●●

REFRDEL Bypass Procedure

The REFRDEL table maintains a list of deleted records from P6 database tables. However, when

an entire project is deleted, a large amount of detailed delete records can be inserted into the

REFRDEL table resulting in the potential for downstream performance degradation when joins are

made to the REFRDEL table.

The REFRDEL Bypass procedure is an alternative to inserting REFRDEL records for tracking

delete records on a large scale. This procedure bypasses the REFRDEL table and simply adds a

single delete record for a deleted project and project ID.

By default, the REFRDEL BYPASS procedure is set to 0 (zero).

To enable REFRDEL Bypass, execute the following procedure and set to a non-zero value:

SQL> exec SET_REFRDEL_PROJECT_BYPASS(1);

Database triggers check for the value of the REFRDEL BYPASS value and process accordingly.

Note: The bypass procedure is meant only for a PROJECT DELETE

operations.

CLEANUP_PRMQUEUE Procedure

This procedure deletes records from the PRMQUEUE table based on the value of the

KeepInterval setting. The remaining settings are similar to the REFRDEL_CLEANUP.

Refer to the following table for information about the settings associated with the

CLEANUP_PRMQUEUE procedure:

CLEANUP_PRMQUEUE Settings

Setting Description: The oldest records to keep in the PRMQUEUE table. Default is five

days.

Namespace

database.cleanup.Prmqueue

Setting Name

KeepInterval

Default Setting

5d

Type

Interval

Setting Description: Determines whether the procedure will delete all of the PRMQUEUE

records possible on each pass.

Namespace

database.cleanup.Prmqueue

Setting Name

DeleteAll

●●●

Default Setting

0 (false)

Type

Boolean

Setting Description: Determines whether all of the records are cleaned. If the total record

count is less than this number then all the records are cleaned.

Namespace

database.cleanup.Prmqueue

Setting Name

DeleteAllThreshold

Default Setting

1,000

Type

Numeric

Setting Description: Percentage of records to delete on each pass.

Namespace

database.cleanup.Prmqueue

Setting Name

DeletePercentage

Default Setting

10(%)

Type

Numeric

Setting Description: Maximum rows to delete on each pass.

Namespace

database.cleanup.Prmqueue

Setting Name

MaxRowsToDelete

Default Setting

10,000

Type

Numeric

USESSION_CLEAR_LOGICAL_DELETES Procedure

This procedure physically deletes all logically deleted USESSION records. This procedure does

not have settings associated with it: All logically deleted USESSION records are cleared.

●●●

CLEANUP_LOGICAL_DELETES Procedure

This procedure removes logically deleted rows based on the value of the KeepInterval setting.

Records in the database can be marked as deleted (logically deleted) by setting the

DELETE_SESSION_ID column to a non-null value. By default, records that were deleted more

than 5 days ago will be deleted by this procedure.

Notes:

. The CLEANUP_LOGICAL_DELETES procedure will not delete

records whose DELETE_SESSION_ID column is set to a negative

value.

. This procedure will not delete records older than the earliest user

session in USESSION, as determined by the minimum value in the

login_date column.

Refer to the following table for information about the settings associated with the

CLEANUP_LOGICAL_DELETES procedure:

CLEANUP_LOGICAL_DELETES Settings

Setting Description: The oldest logically deleted records to keep in tables.

Namespace

database.cleanup.LogicalDelete

Setting Name

KeepInterval

Default Setting

5d

Type

Interval

Setting Description: Determines whether the procedure will delete all of the logically

deleted records possible on each pass.

Namespace

database.cleanup.LogicalDelete

Setting Name

DeleteAll

Default Setting

0 (false)

Type

Boolean

Setting Description: Maximum rows to delete on each pass.

Namespace

database.cleanup.LogicalDelete

Setting Name

MaxRowsToDelete

Default Setting

10,000

Type

Numeric

●●●

PRMAUDIT_CLEANUP Procedure

If the auditing feature is enabled, this procedure will physically delete records from the table based

on the value of the KeepInterval setting.

Refer to the following table for information about the settings associated with the

PRMAUDIT_CLEANUP procedure:

PRMAUDIT_CLEANUP Settings

Setting Description: Should the procedure attempt PRMAUDIT records cleanup.

Namespace

database.cleanup.auditing

Setting Name

Enabled

Default Setting

1 (true)

Type

Boolean

Setting Description: The oldest audit records to keep in PRMAUDIT.

Namespace

database.cleanup.auditing

Setting Name

KeepInterval

Default Setting

30d

Type

Interval

●●●

CLEANUP_USESSAUD Procedure

The CLEANUP_USESSAUD procedure deletes records from the USESSAUD table based on the

KeepInterval parameter setting. All other settings are similar to the REFRDEL_CLEANUP

procedure. The following table describes the settings associated with the CLEANUP_USESSAUD

procedure.

CLEANUP_USESSAUD Settings

Setting Description: Determines the oldest records to keep in the USESSAUD table.

Based on the logout time, data beyond the KeepInterval parameter value will not deleted.

The KeepInterval parameter setting overrides all other CLEANUP_USESSAUD settings.

Namespace

database.cleanup.Usessaud

Setting Name

KeepInterval

Default Setting

5d

Type

Interval

Setting Description: Deletes all the REFRDEL records that satisfy the KeepInterval

setting on each pass. The DeleteAll parameter setting overrides the settings of

DeleteAllThreshold, DeletePercentage, and MaxRowsToDelete parameters.

Namespace

database.cleanup.Usessaud

Setting Name

DeleteAll

Default Setting

0 (false)

Type

Boolean

Setting Description: Determines the minimum number of records to delete after

satisfying the KeepInterval parameter setting. By default, a minimum of 1000 records are

deleted. If the total record count is less than this setting, all records are deleted. The

DeleteAllThreshold parameter setting overrides the settings of the DeletePercentage

and MaxRowsToDelete parameters.

Namespace

database.cleanup.Usessaud

Setting Name

DeleteAllThreshold

Default Setting

1,000

Type

Numeric

Setting Description: Determines the maximum rows to delete on each pass after

satisfying the KeepInterval parameter setting. The MaxRowsToDelete parameter setting

overrides the DeletePercentage parameter setting.

Namespace

database.cleanup.Usessaud

Setting Name

MaxRowsToDelete

Default Setting

10,000

●●●

Type

Numeric

Setting Description: Determines the percentage of records to delete on each pass after

satisfying the DeleteAllThreshold and MaxRowsToDelete settings. However, the

percentage of records deleted is limited to the default value of the MaxRowsToDelete

setting.

Namespace

database.cleanup.Usessaud

Setting Name

DeletePercentage

Default Setting

10 (%)

Type

Numeric

●●●

USER_DEFINED_BACKGROUND Procedure

This procedure is an optional customer procedure that DAMON runs. This procedure does not

have settings associated with it.

Oracle Database Performance

You can modify several Oracle database settings to improve the performance of your P6 EPPM

database. Run the scripts as described below after you create the database.

Grant access to the V_$TRANSACTION view:

V_$TRANSACTION is a system view in Oracle that lists the active transactions in the system.

GET_SAFETY DATE (a procedure in the Project Management schema) accesses this view to get

the oldest start time of an active transaction. If the schema owner does not have privileges to this

view, then it returns a safety date using the USESSION table. V_$Transaction tunes performance

during a refresh action. USESSION records the login time of the logged in user, whereas data in

the V_$Transaction view is recorded at a system level. The logged in user could be logged in for

more than an hour (as seen from the USESSION table), but the V_$Transaction view has the

current transaction datetime, regardless of the time the user logged in.

Note: Access to the V_$TRANSACTION view was built into the procedure

to tune performance with refreshing operations; however, third party

functions could impact performance with database refresh operations that

use an older time in the V_$TRANSACTION view.

To grant access to this view, connect to Oracle as SYS. Run the RUN_AS_SYS.SQL script

located in the \Database\scripts\common folder of the P6 EPPM physical media or download.

Gather statistics for cost-based optimization:

Oracle 11g and later supports only cost-based optimization, which relies on accurate statistics to

determine the optimal access path for a query. To gather the appropriate sta