Friday, February 3, 2017

Convert Common Oracle Application Express in a CDB to Local APEX in PDBs

Introduction

When Oracle Multitenant was released with Oracle Database 12.1.0.1.0 in June 2013,  Oracle Application Express was installed by default common in the CDB in CDB$ROOT, PDB$SEED, and all PDBs. In fact, that was the architecture that we recommended at that time. As we have gained experience with multitenant in our internal deployments, we realized that our initial recommendation was wrong. Having APEX installed common locks you in to one version for your entire CDB, and when you need to upgrade APEX, you have to upgrade every PDB, even if that PDB is not using APEX. This would cause unnecessary added time to APEX upgrades.

Applying the lessons we have learned in our internal deployments, we have been recommending that customers remove Oracle Application Express from their CDBs and install APEX locally in PDBs since version 5.0.

What do you do if you have been using the common APEX from 12.1.0.1.0 or 12.1.0.2.0, and now you want to follow our new recommendation of having APEX installed locally in a PDB? We have been asked that question many times by both internal and external customers. Unfortunately there is no simple answer, no magic SQL script you can run to do the conversion, so we have never really had a good answer.

Then my manager, Joel Kallman, had a novel idea. He reminded me of the work I did for the Oracle Database Cloud Schema Service, to effectively export almost every single artifact of a workspace, using the command line utility APEXExport, so that a schema service tenant could be moved from one APEX instance to another. This involved greatly expanding our workspace export code, modifying APEXExport to allow for more export options, and then scripting the calls to APEXExport, including creating an installer script to invoke all the exports, and finally zipping the scripts produced. Joel's idea was to reuse this method in a process to convert a CDB where APEX is installed common, to a CDB where APEX is installed locally in PDBs.

The Big Idea

The high level steps to convert common APEX in a CDB to local APEX in PDBs are:

  1. Identify all PDBs in your CDB that have APEX instances
  2. In each PDB, identify all workspaces
  3. Run a script to export all artifacts of all workspaces identified in step 1 into zip files with installers
  4. Completely back up your CDB
  5. Run the APEX removal script to remove APEX from the CDB and all PDBs
  6. Install APEX locally in each PDB identified in step 1. (This may be a good opportunity to upgrade to the latest version!)
  7. Unzip each of your files from setp 3, and run the installer script from each, connected to the appropriate PDB

The Setup

I have a 12.1.0.2.0 CDB with two PDBs running APEX. One PDB has multiple workspaces, the other PDB has only one workspace. The CDB is the default APEX 4.2.5.0.00.08 that shipped with 12.1.0.2.0. The workspaces may have SQL scripts uploaded to SQL Workshop, SQL History and Saved SQL that we want to preserve. There are sample and packaged applications that we want to preserve. There are also custom built applications on objects in the schema associated with the workspaces. There are workspace images, and static files that we also want to preserve. I have already completely backed up my CDB.

HR Workspace in APEX1 figures

Applications in HR

SQL Script in SQL Workshop

SQL History in HR

Workspace image in HR

Static file in HR

FINANCE Workspace in APEX1 figures

Applications in FINANCE workspace

Saved SQL in SQL Workshop

MARKETING Workspace in APEX2 figures

Applications in MARKETING workspace

Workspace Images in MARKETING workspace

Saved SQL in SQL Workshop

The Hook

Identify all PDBs that have APEX instances

SQL> select p.pdb_name, r.version, r.status from sys.dba_pdbs p, sys.cdb_registry r where p.pdb_id = r.con_id and r.comp_id = 'APEX' order by 1;

PDB_NAME               VERSION                  STATUS
------------------------------ ------------------------------ -----------
APEX1                   4.2.5.00.08              VALID
APEX2                   4.2.5.00.08              VALID


Identify all workspaces

SQL> set num 40      
SQL> alter session set container=APEX1;

Session altered.

SQL> select workspace_id from apex_workspaces where workspace_id > 100;

                WORKSPACE_ID
----------------------------------------
            2222525459993115
            2336806112004961

SQL> alter session set container=APEX2;

Session altered.

SQL> select workspace_id from apex_workspaces where workspace_id > 100;

                WORKSPACE_ID
----------------------------------------
            2224405822867543

Run a script to export all artifacts

The original script that I wrote was in C shell and did the job, but my colleague Vlad Uvarov rewrote it in bash (apparently anyone under 40 no longer uses C shell) and vastly improved it. A slightly revised version of the script is listed below.

#!/bin/bash -e

THIS_SCRIPT=$(basename "$0" )
THIS_DIR=$(cd "$(dirname "$0" )" && pwd )
CURRENT_DIR=$(pwd )

# ===================================================================================
# Function that displays script usage instructions and terminates the script
#
f_usage () {
    cat <<EOF
Usage: $THIS_SCRIPT <JDBC connection string> <user> <password> <workspace ID>

Parameters:
    JDBC connection string    Database connection URL in JDBC format
    user                      Database username
    password                  Password of the database user
    workspace ID              ID of the workspace to be exported

Example:
    ./$THIS_SCRIPT //apex.example.com:1521/orcl apex_040200 secret 1234567890
EOF
    exit 1
}

# ===================================================================================
# First, check environment variables and input parameters
#
[ -z "$ORACLE_HOME" ] && echo "Error: ORACLE_HOME environment variable is not set." && exit 1

JAVA_EXE=$ORACLE_HOME/jdk/bin/java
[ ! -x "$JAVA_EXE" ] && echo "Error: Java executable not found ($JAVA_EXE)." && exit 1

OJDBC_JAR=$ORACLE_HOME/jdbc/lib/ojdbc6.jar
[ ! -f "$OJDBC_JAR" ] && echo "Error: Oracle JDBC library not found ($OJDBC_JAR)." && exit 1

APEXEXPORT=$ORACLE_HOME/apex/utilities/oracle/apex/APEXExport.class
[ ! -f "$THIS_DIR/$APEXEXPORT" -a ! -f "$APEXEXPORT" ] && echo "Error: Missing APEXExport utility ($APEXEXPORT)." && exit 1

(( $# < 4 )) && echo "Error: This script requires 4 parameters." && echo && f_usage

# ===================================================================================
# Step 1: Export APEX workspace, including applications and files
#
EXP_DIR=$(mktemp -d ${TMPDIR:-/tmp}/$(basename "$THIS_SCRIPT" .sh ).XXXXXX )
cd "$EXP_DIR"

cat <<EOF
Oracle Application Express workspace export

Using ORACLE_HOME=$ORACLE_HOME
EOF
$JAVA_EXE -version
echo

CP=$OJDBC_JAR:$THIS_DIR:$ORACLE_HOME/apex/utilities
if [ "$THIS_DIR" != "$CURRENT_DIR" ]; then
    CP=$CP:$CURRENT_DIR
fi

$JAVA_EXE -cp $CP oracle.apex.APEXExport -db "$1" -user "$2" -password "$3" -workspaceid "$4" -expWorkspace -expTeamdevdata
$JAVA_EXE -cp $CP oracle.apex.APEXExport -db "$1" -user "$2" -password "$3" -workspaceid "$4" -expFiles
$JAVA_EXE -cp $CP oracle.apex.APEXExport -db "$1" -user "$2" -password "$3" -workspaceid "$4" -expLocked -expSavedReports

# ===================================================================================
# Step 2: Create ZIP archive with a generated installation script and all export files
#
INSTALL_SCRIPT=install_${4}.sql
cat > "$INSTALL_SCRIPT" <<EOF
prompt
spool install_${4}.log

prompt Oracle Application Express workspace export
prompt Workspace ID $4 exported on $(date )

alter session set current_schema = APEX_050100;

@@w${4}.sql
EOF

for f in *.sql; do
    if [ "$f" != "w${4}.sql" -a "$f" != "$INSTALL_SCRIPT" ]; then
        echo "@@$f" >> "$INSTALL_SCRIPT"
    fi
done

cat >> "$INSTALL_SCRIPT" <<EOF

spool off
prompt
exit
EOF

echo
ZIP_FILE="$CURRENT_DIR/install_${4}_$(date +%Y%m%d ).zip"
rm -f "$ZIP_FILE"
zip -9 "$ZIP_FILE" *.sql

echo
echo "Generated $ZIP_FILE"
echo

# ===================================================================================
# Step 3: Clean up
#
cd "$CURRENT_DIR"
rm -rf "$EXP_DIR"
workspace_export.sh

One thing to note in the script above is that the install script being generated assumes that APEX 5.1 is installed in your target APEX instance. If that is not your plan, change the line "alter session set current_schema = APEX_050100" to match the APEX schema of the version you plan to install locally in your PDBs.

Also, for convenience, I am going to temporarily unlock APEX_040200 in my CDB and set a known password, and pass those necessary credentials to the workspace_export.sh script. You could really use any database user that has been granted the APEX_ADMINISTRATOR_ROLE.

SQL> alter user apex_040200 account unlock identified by oracle container=all;

User altered.


I saved the script above in a directory where I want all my zip files to end up. Now I will call the script passing each of the workspace IDs I identified in the previous step.

[jstraub@slc02otv cdbconvertapex]$ ./workspace_export.sh //localhost:1521/APEX1 APEX_040200 oracle 2222525459993115
Oracle Application Express workspace export

Using ORACLE_HOME=/scratch/jstraub/app/product/12.1.0/dbhome_1
java version "1.6.0_75"
Java(TM) SE Runtime Environment (build 1.6.0_75-b13)
Java HotSpot(TM) 64-Bit Server VM (build 20.75-b01, mixed mode)

Exporting Workspace 2222525459993115:'HR'
  Completed at Fri Feb 03 08:29:07 PST 2017
Exporting Application 100:'Sample Database Application'
  Completed at Fri Feb 03 08:29:16 PST 2017
Exporting Application 102:'Checklist Manager'
  Completed at Fri Feb 03 08:29:17 PST 2017
Exporting Application 103:'EMPLOYEES'
  Completed at Fri Feb 03 08:29:18 PST 2017
Exporting Application 104:'Sample Websheet Application - Big Cats'
  Completed at Fri Feb 03 08:29:18 PST 2017

  adding: f100.sql (deflated 88%)
  adding: f102.sql (deflated 89%)
  adding: f103.sql (deflated 93%)
  adding: files_2222525459993115.sql (deflated 55%)
  adding: install_2222525459993115.sql (deflated 39%)
  adding: w2222525459993115.sql (deflated 87%)
  adding: ws104.sql (deflated 64%)

Generated /scratch/jstraub/cdbconvertapex/install_2222525459993115_20170203.zip


[jstraub@slc02otv cdbconvertapex]$ ./workspace_export.sh //localhost:1521/APEX1 APEX_040200 oracle 2336806112004961
Oracle Application Express workspace export

Using ORACLE_HOME=/scratch/jstraub/app/product/12.1.0/dbhome_1
java version "1.6.0_75"
Java(TM) SE Runtime Environment (build 1.6.0_75-b13)
Java HotSpot(TM) 64-Bit Server VM (build 20.75-b01, mixed mode)

Exporting Workspace 2336806112004961:'FINANCE'
  Completed at Fri Feb 03 10:17:59 PST 2017
Exporting Application 101:'Sample Database Application'
  Completed at Fri Feb 03 10:18:13 PST 2017
Exporting Application 105:'Group Calendar'
  Completed at Fri Feb 03 10:18:14 PST 2017
Exporting Application 106:'QUOTES'
  Completed at Fri Feb 03 10:18:14 PST 2017

  adding: f101.sql (deflated 88%)
  adding: f105.sql (deflated 89%)
  adding: f106.sql (deflated 93%)
  adding: files_2336806112004961.sql (deflated 64%)
  adding: install_2336806112004961.sql (deflated 39%)
  adding: w2336806112004961.sql (deflated 82%)

Generated /scratch/jstraub/cdbconvertapex/install_2336806112004961_20170203.zip


And then for the other PDB, APEX2, we pass a different connect string:

[jstraub@slc02otv cdbconvertapex]$ ./workspace_export.sh //localhost:1521/APEX2 APEX_040200 oracle 2224405822867543
Oracle Application Express workspace export

Using ORACLE_HOME=/scratch/jstraub/app/product/12.1.0/dbhome_1
java version "1.6.0_75"
Java(TM) SE Runtime Environment (build 1.6.0_75-b13)
Java HotSpot(TM) 64-Bit Server VM (build 20.75-b01, mixed mode)

Exporting Workspace 2224405822867543:'MARKETING'
  Completed at Fri Feb 03 10:20:04 PST 2017
Exporting Application 100:'Sample Database Application'
  Completed at Fri Feb 03 10:20:13 PST 2017
Exporting Application 101:'Sample Websheet Application - AnyCo IT Department'
  Completed at Fri Feb 03 10:20:13 PST 2017
Exporting Application 102:'PROJECT_TASKS'
  Completed at Fri Feb 03 10:20:14 PST 2017
Exporting Application 103:'Decision Manager'
  Completed at Fri Feb 03 10:20:14 PST 2017
Exporting Application 104:'P-Track'
  Completed at Fri Feb 03 10:20:17 PST 2017

  adding: f100.sql (deflated 88%)
  adding: f102.sql (deflated 93%)
  adding: f103.sql (deflated 89%)
  adding: f104.sql (deflated 89%)
  adding: files_2224405822867543.sql (deflated 54%)
  adding: install_2224405822867543.sql (deflated 40%)
  adding: w2224405822867543.sql (deflated 82%)
  adding: ws101.sql (deflated 58%)

Generated /scratch/jstraub/cdbconvertapex/install_2224405822867543_20170203.zip

The long game

I have a complete backup of my database, and I have all the zip files that will reconstruct my workspaces. It is time to do the actual conversion.

Remove APEX from the CDB and all PDBs

Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options

SQL> @apxremov_con.sql

PL/SQL procedure successfully completed.

Performing installation in multitenant container database in the background.
The installation progress is spooled into apxremov*_con*.log files.

Please wait...

catcon: ALL catcon-related output will be written to apxremov1_con_catcon_9311.lst
catcon: See apxremov1_con*.log files for output generated by scripts
catcon: See apxremov1_con_*.lst files for spool files, if any
catcon.pl: completed successfully

catcon: ALL catcon-related output will be written to apxremov2_con_catcon_9723.lst
catcon: See apxremov2_con*.log files for output generated by scripts
catcon: See apxremov2_con_*.lst files for spool files, if any
catcon.pl: completed successfully


Installation completed. Log files for each container can be found in:

apxremov*_con*.log

You can quickly scan for ORA errors or compilation errors by using a utility
like grep:

grep ORA- *.log
grep PLS- *.log

Install APEX 5.1 locally in the PDBs

SQL> alter session set container=APEX1;

Session altered.

SQL> @apexins.sql SYSAUX SYSAUX TEMP /i/


SQL> @apex_rest_config.sql

SQL> @apxchpwd.sql

SQL> @apex_epg_config.sql /scratch/jstraub/apx51 -- only if you are using EPG, very doubtful

SQL> alter session set container=APEX2;

Session altered.

SQL> @apexins.sql SYSAUX SYSAUX TEMP /i/

 
SQL> @apex_rest_config.sql

SQL> @apxchpwd.sql

SQL> @apex_epg_config.sql /scratch/jstraub/apx51 -- only if you are using EPG, very doubtful

Recreate the workspaces using the generated zip files

First, I am again going to temporarily unlock and change the password for the APEX database user, in this case APEX_050100. Since now APEX_050100 is a local user to the PDB, I have to do it in both APEX1 and APEX2 PDBs.

SQL> alter session set container=APEX1;

Session altered.


SQL> alter user APEX_050100 account unlock identified by oracle;

User altered.


SQL> alter session set container=APEX2;

Session altered.

SQL> alter user APEX_050100 account unlock identified by oracle;

User altered.


Then I unzip each complete workspace export and run the corresponding install script.

[jstraub@slc02otv cdbconvertapex]$ mkdir hr
[jstraub@slc02otv cdbconvertapex]$ unzip install_2222525459993115_20170203.zip -d hr
[jstraub@slc02otv cdbconvertapex]$ cd hr
[jstraub@slc02otv hr]$ sqlplus apex_050100/oracle@localhost/APEX1

SQL*Plus: Release 12.1.0.2.0 Production on Fri Feb 3 12:05:24 2017

Copyright (c) 1982, 2014, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options

SQL> @install_2222525459993115.sql  


[jstraub@slc02otv cdbconvertapex]$ mkdir finance
[jstraub@slc02otv cdbconvertapex]$ unzip install_2336806112004961_20170203.zip -d finance
[jstraub@slc02otv cdbconvertapex]$ cd finance
[jstraub@slc02otv finance]$ sqlplus apex_050100/oracle@localhost/APEX1

SQL*Plus: Release 12.1.0.2.0 Production on Fri Feb 3 12:14:21 2017

Copyright (c) 1982, 2014, Oracle.  All rights reserved.

Last Successful login time: Fri Feb 03 2017 12:05:24 -08:00

Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options

SQL> @install_2336806112004961.sql 


[jstraub@slc02otv cdbconvertapex]$ mkdir marketing
[jstraub@slc02otv cdbconvertapex]$ unzip install_2224405822867543_20170203.zip -d marketing
[jstraub@slc02otv marketing]$ sqlplus apex_050100/oracle@localhost/APEX2

SQL*Plus: Release 12.1.0.2.0 Production on Fri Feb 3 12:16:11 2017

Copyright (c) 1982, 2014, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options

SQL> @install_2224405822867543.sql


Now we login to each workspace and check that all the artifacts from the workspace migrated over.

HR workspace in APEX1 figures - APEX 5.1

Applications in HR Workspace

Static Files and Images in HR Workspace

SQL Script in SQL Workshop

SQL History in SQL Workshop

FINANCE workspace in APEX1 figures - APEX 5.1

Applications in FINANCE Workspace

Saved SQL in SQL Workshop

MARKETING workspace in APEX2 figures - APEX 5.1

Applications in MARKETING Workspace

Static Workspace Files in MARKETING

Saved SQL in SQL Workshop

One more thing

Actually, two more things. First, this process will not bring over "Template Applications" and "Public Themes." These features are not well known and rarely used, but you can easily determine if you have them by logging into internal administration, click on Manage Instance, and then click the Public Themes and Template Applications links. If there are applications in either area, simply export them, and them import them into internal administration after you recreate your workspaces.

Second, you may want to create another PDB, call it APEX51SEED, and install APEX into it. Put the PDB in read only mode, and then when you create a new PDB, you can create it from APEX51SEED and it will already have APEX 5.1 installed locally. In our case, we could not use this method to install APEX only once, because we needed the schemas that were in our APEX1 and APEX2 PDBs.

Conclusion

Having APEX installed locally in PDBs provides greater flexibility in your CDB, reduces upgrade time, and as well simplifies unplug/plug operations of your PDBs between CDBs. If you have a CDB where APEX is installed common, and you are using APEX in some or all of those PDBs, it is possible to do an in-place conversion using the method described above. Unfortunately, there is no magic SQL or script that can simplify this process. I hope you are successful if you go down this path, but be sure you have a complete backup of your CDB before trying. You can also use parts of this method to simply move a workspace from one APEX instance to another. That would require you to also move the schema, using datapump or another utility.

Friday, January 6, 2017

Ooops... I did it again.

APEX 5.1 is released! As Shaun points out at this forum post, the appendix of the Oracle Application Express 5.1 Installation Guide is missing instructions to downgrade back to 5.0, after a failed upgrade attempt.

My bad. I signed off on the Oracle Application Express Installation Guide as being complete for 5.1. Unfortunately, I did not pay enough attention to the appendix. We will get this corrected soon in a refreshed version of the Installation Guide, but in the meantime, below are the instructions we will be including.


Reverting to Release 5.0 in a non-CDB
To revert to a previous Oracle Application Express release 5.0 in a non-CDB:
  1. If you altered your images directory, revert it back to the release you want to revert to. See "Reverting the Images Directory."
  2. Change your working directory to apex/core in the 5.0 source.
  3. Start SQL*Plus and connect to the database where Oracle Application Express is installed as SYS specifying the SYSDBA role:
On Windows:
SYSTEM_DRIVE:\ sqlplus /nolog
SQL> CONNECT SYS as SYSDBA
Enter password: SYS_password 

On UNIX and Linux:
$ sqlplus /nolog
SQL> CONNECT SYS as SYSDBA
Enter password: SYS_password
  1. Execute the following commands:
alter session set current_schema = SYS;   

@wwv_flow_val.sql 
@wwv_flow_val.plb 

begin
     dbms_utility.compile_schema('APEX_050000');
end;
/ 

set define '^'   
@validate_apex x x APEX_050000

begin
  for i in ( select owner, trigger_name
               from sys.dba_triggers
              where owner        =    'APEX_050000'
                and trigger_name like 'WWV_FLOW_UPGRADE_%'
              order by 1 )
  loop
    sys.dbms_output.put_line('Dropping trigger '||i.owner||'.'||i.trigger_name);
    execute immediate 'drop trigger '||i.owner||'.'||i.trigger_name;
  end loop;
end;
/

ALTER SESSION SET CURRENT_SCHEMA = APEX_050000; 
exec apex_050000.wwv_flow_upgrade.switch_schemas('APEX_050100','APEX_050000');
ALTER SESSION SET CURRENT_SCHEMA = SYS; 
drop context APEX$SESSION;
create context APEX$SESSION using APEX_050000.WWV_FLOW_SESSION_CONTEXT;
declare
     l_apex_version varchar2(30); 
     l_schemas sys.dbms_registry.schema_list_t;
begin
     l_apex_version := apex_050000.wwv_flows_release;
     dbms_registry.downgrading('APEX','Oracle Application Express','validate_apex','APEX_050000');
     dbms_registry.downgraded('APEX',l_apex_version);
     select username
       bulk collect into l_schemas
       from all_users
      where username in ('FLOWS_FILES','APEX_PUBLIC_USER','APEX_LISTENER','APEX_REST_PUBLIC_USER','APEX_INSTANCE_ADMIN_USER')
      order by 1;
     sys.dbms_registry.update_schema_list('APEX', l_schemas);
     validate_apex;
end;
/
  1. See the next section, "Removing the Oracle Application Express Release 5.1 Schema."


Reverting to Release 5.0 in a CDB

To revert to a previous Oracle Application Express release 5.0 in a CDB:
  1. If you altered your images directory, revert it back to the release you want to revert to. See "Reverting the Images Directory."
  2. Change your working directory to apex/core in the 5.0 source.
  3. Create a new text file in that directory named apx50dgrd1.sql consisting of the following:
alter session set current_schema = SYS;   

@wwv_flow_val.sql 
@wwv_flow_val.plb 

begin
     dbms_utility.compile_schema('APEX_050000');
end;
/ 

set define '^'   
@validate_apex x x APEX_050000

begin
  for i in ( select owner, trigger_name
               from sys.dba_triggers
              where owner        =    'APEX_050000'
                and trigger_name like 'WWV_FLOW_UPGRADE_%'
              order by 1 )
  loop
    sys.dbms_output.put_line('Dropping trigger '||i.owner||'.'||i.trigger_name);
    execute immediate 'drop trigger '||i.owner||'.'||i.trigger_name;
  end loop;
end;
/

ALTER SESSION SET CURRENT_SCHEMA = APEX_050000; 
exec apex_050000.wwv_flow_upgrade.switch_schemas('APEX_050100','APEX_050000');
ALTER SESSION SET CURRENT_SCHEMA = SYS; 
drop context APEX$SESSION;
create context APEX$SESSION using APEX_050000.WWV_FLOW_SESSION_CONTEXT;
declare
     l_apex_version varchar2(30); 
     l_schemas sys.dbms_registry.schema_list_t;
begin
     l_apex_version := apex_050000.wwv_flows_release;
     dbms_registry.downgrading('APEX','Oracle Application Express','validate_apex','APEX_050000');
     dbms_registry.downgraded('APEX',l_apex_version);
     select username
       bulk collect into l_schemas
       from all_users
      where username in ('FLOWS_FILES','APEX_PUBLIC_USER','APEX_LISTENER','APEX_REST_PUBLIC_USER','APEX_INSTANCE_ADMIN_USER')
      order by 1;
     sys.dbms_registry.update_schema_list('APEX', l_schemas);
     validate_apex;
end;
/
  1. Create a second new text file in that directory named apx50dgrd.sql consisting of the following:
set define '^'   
whenever sqlerror exit   
column :xe_home new_value OH_HOME NOPRINT 
variable xe_home varchar2(255)   
set serverout on 
begin 
-- get oracle_home     
sys.dbms_system.get_env('ORACLE_HOME',:xe_home);     
if length(:xe_home) = 0 then
    sys.dbms_output.put_line(lpad('-',80,'-'));         
    raise_application_error (-20001,'Oracle Home environment variable not set' );  
end if; 
end; 
/ 
whenever sqlerror continue   
set termout off 
select :xe_home from sys.dual; 
set termout on   
host ^OH_HOME/perl/bin/perl -I ^OH_HOME/rdbms/admin ^OH_HOME/rdbms/admin/catcon.pl -b apx50dgrd apx50dgrd1.sql
  1. Start SQL*Plus and connect to CDB$ROOT of the database where Oracle Application Express is installed as SYS specifying the SYSDBA role:
On Windows:
SYSTEM_DRIVE:\ sqlplus /nolog
SQL> CONNECT SYS as SYSDBA
Enter password: SYS_password

On UNIX and Linux:
$ sqlplus /nolog
SQL> CONNECT SYS as SYSDBA
Enter password: SYS_password
  1. Execute the following commands:
@apx50dgrd.sql
  1. See the next section, "Removing the Oracle Application Express Release 5.1 Schema."