Archive for the ‘Linux’ Category
Fedora 30 Missing Library
Having run into an obsolete library issue installing Oracle Database 18c XE on Fedora, Version 30, I opted to revert my student image to Oracle Database 11g XE. The installation went without issue but when I tried to log into SQL*Plus as the oracle user, I got the following error message:
sqlplus: error while loading shared libraries: libnsl.so.1: cannot open shared object file: No such file or directory |
The libnsl.so.1 library is no longer installed as part of the distribution for Fedora 28 forward but you can install it with the yum tool, like:
yum install -y libnsl |
Display detailed console log →
Last metadata expiration check: 1:35:44 ago on Sun 11 Aug 2019 07:28:07 PM MDT. Dependencies resolved. ============================================================================= Package Architecture Version Repository Size ============================================================================= Installing: libnsl x86_64 2.29-15.fc30 updates 97 k Transaction Summary ============================================================================= Install 1 Package Total download size: 97 k Installed size: 287 k Downloading Packages: libnsl-2.29-15.fc30.x86_64.rpm 134 kB/s | 97 kB 00:00 ----------------------------------------------------------------------------- Total 69 kB/s | 97 kB 00:01 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : libnsl-2.29-15.fc30.x86_64 1/1 Running scriptlet: libnsl-2.29-15.fc30.x86_64 1/1 Verifying : libnsl-2.29-15.fc30.x86_64 1/1 Installed: libnsl-2.29-15.fc30.x86_64 Complete! |
If you attempted to run the oracle-xe utility to configure the database prior to adding this library, it fails to provision the instance without a message. You won’t get the message until you manually try to connect as the sysdba privileged user. At that point, you’ll determine the instance wasn’t provisioned.
You can see that the installation failed when the oracle-xe utility fails to print the following lines to the console after the options are entered:
Starting Oracle Net Listener...Done Configuring database...Done Starting Oracle Database 11g Express Edition instance...Done Installation completed successfully. |
After installing the missing library, the oracle-xe utility works correctly. Alas, it looks like I’ll never bother to sort the Oracle Database 18c XE issues because after this version of the image we are moving the courses to a PostgreSQL database. PostgreSQL offers the smaller footprint that supports the core learning objectives of the courses.
As always, I hope this helps those looking for a solution.
Fedora 30 Install Chrome
While building the new Fedora 30 Linux instance for my students, I needed to install the Google Chrome browser. Here are the instructions for installing the Chrome browser.
- As the root user, create the
google-chrome.repofile in the/etc/yum.repos.ddirectory with the following information:[chrome] name=google-chrome baseurl=http://dl.google.com/linux/chrome/rpm/stable/x86_64 enabled=1 gpgcheck=1 gpgkey=https://dl-ssl.google.com/linux/linux_signing_key.pub
- Next, use the yum utility to install the Chrome browser:
yum install -y google-chrome
You should see the following log information:
Display detailed console log →
Last metadata expiration check: 0:00:28 ago on Fri 09 Aug 2019 11:39:07 PM MDT. Dependencies resolved. ============================================================================= Package Arch Version Repo Size ============================================================================= Installing: google-chrome-unstable x86_64 78.0.3876.0-1 chrome 61 M Installing dependencies: libappindicator-gtk3 x86_64 12.10.0-24.fc30 fedora 40 k libdbusmenu x86_64 16.04.0-11.fc30 fedora 135 k libdbusmenu-gtk3 x86_64 16.04.0-11.fc30 fedora 37 k liberation-fonts noarch 1:2.00.5-1.fc30 fedora 8.0 k libindicator-gtk3 x86_64 12.10.1-14.fc30 fedora 65 k redhat-lsb-core x86_64 4.1-47.fc30 fedora 32 k redhat-lsb-submod-security x86_64 4.1-47.fc30 fedora 8.9 k spax x86_64 1.5.3-16.fc30 fedora 202 k Transaction Summary ============================================================================= Install 9 Packages Total download size: 62 M Installed size: 218 M Downloading Packages: (1/9): libdbusmenu-gtk3-16.04.0-11.fc30.x86_ 97 kB/s | 37 kB 00:00 (2/9): libappindicator-gtk3-12.10.0-24.fc30. 92 kB/s | 40 kB 00:00 (3/9): liberation-fonts-2.00.5-1.fc30.noarch 76 kB/s | 8.0 kB 00:00 (4/9): libdbusmenu-16.04.0-11.fc30.x86_64.rp 256 kB/s | 135 kB 00:00 (5/9): redhat-lsb-core-4.1-47.fc30.x86_64.rp 290 kB/s | 32 kB 00:00 (6/9): libindicator-gtk3-12.10.1-14.fc30.x86 348 kB/s | 65 kB 00:00 (7/9): redhat-lsb-submod-security-4.1-47.fc3 94 kB/s | 8.9 kB 00:00 (8/9): spax-1.5.3-16.fc30.x86_64.rpm 874 kB/s | 202 kB 00:00 (9/9): google-chrome-unstable-78.0.3876.0-1. 10 MB/s | 61 MB 00:05 ----------------------------------------------------------------------------- Total 9.1 MB/s | 62 MB 00:06 warning: /var/cache/dnf/fedora-a924e206df91842b/packages/libappindicator-gtk3-12.10.0-24.fc30.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID cfc659b9: NOKEY Fedora 30 - x86_64 1.6 MB/s | 1.6 kB 00:00 Importing GPG key 0xCFC659B9: Userid : "Fedora (30) <fedora-30-primary@fedoraproject.org>" Fingerprint: F1D8 EC98 F241 AAF2 0DF6 9420 EF3C 111F CFC6 59B9 From : /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-30-x86_64 Key imported successfully warning: /var/cache/dnf/chrome-eb0d6f10ccbdafba/packages/google-chrome-unstable-78.0.3876.0-1.x86_64.rpm: Header V4 DSA/SHA1 Signature, key ID 7fac5991: NOKEY google-chrome 30 kB/s | 7.8 kB 00:00 Importing GPG key 0x7FAC5991: Userid : "Google, Inc. Linux Package Signing Key <linux-packages-keymaster@google.com>" Fingerprint: 4CCA 1EAF 950C EE4A B839 76DC A040 830F 7FAC 5991 From : https://dl-ssl.google.com/linux/linux_signing_key.pub Key imported successfully Importing GPG key 0xD38B4796: Userid : "Google Inc. (Linux Packages Signing Authority) <linux-packages-keymaster@google.com>" Fingerprint: EB4C 1BFD 4F04 2F6D DDCC EC91 7721 F63B D38B 4796 From : https://dl-ssl.google.com/linux/linux_signing_key.pub Key imported successfully Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : libdbusmenu-16.04.0-11.fc30.x86_64 1/9 Installing : libdbusmenu-gtk3-16.04.0-11.fc30.x86_64 2/9 Installing : spax-1.5.3-16.fc30.x86_64 3/9 Running scriptlet: spax-1.5.3-16.fc30.x86_64 3/9 Installing : redhat-lsb-submod-security-4.1-47.fc30.x86_64 4/9 Installing : redhat-lsb-core-4.1-47.fc30.x86_64 5/9 Installing : libindicator-gtk3-12.10.1-14.fc30.x86_64 6/9 Installing : libappindicator-gtk3-12.10.0-24.fc30.x86_64 7/9 Installing : liberation-fonts-1:2.00.5-1.fc30.noarch 8/9 Running scriptlet: google-chrome-unstable-78.0.3876.0-1.x86_64 9/9 Installing : google-chrome-unstable-78.0.3876.0-1.x86_64 9/9 Running scriptlet: google-chrome-unstable-78.0.3876.0-1.x86_64 9/9 /var/tmp/rpm-tmp.AQSZLu: line 612: service: command not found Verifying : libappindicator-gtk3-12.10.0-24.fc30.x86_64 1/9 Verifying : libdbusmenu-16.04.0-11.fc30.x86_64 2/9 Verifying : libdbusmenu-gtk3-16.04.0-11.fc30.x86_64 3/9 Verifying : liberation-fonts-1:2.00.5-1.fc30.noarch 4/9 Verifying : libindicator-gtk3-12.10.1-14.fc30.x86_64 5/9 Verifying : redhat-lsb-core-4.1-47.fc30.x86_64 6/9 Verifying : redhat-lsb-submod-security-4.1-47.fc30.x86_64 7/9 Verifying : spax-1.5.3-16.fc30.x86_64 8/9 Verifying : google-chrome-unstable-78.0.3876.0-1.x86_64 9/9 Installed: google-chrome-unstable-78.0.3876.0-1.x86_64 libappindicator-gtk3-12.10.0-24.fc30.x86_64 libdbusmenu-16.04.0-11.fc30.x86_64 libdbusmenu-gtk3-16.04.0-11.fc30.x86_64 liberation-fonts-1:2.00.5-1.fc30.noarch libindicator-gtk3-12.10.1-14.fc30.x86_64 redhat-lsb-core-4.1-47.fc30.x86_64 redhat-lsb-submod-security-4.1-47.fc30.x86_64 spax-1.5.3-16.fc30.x86_64 Complete!
- Click the following “f” icon in the lower left corner to bring up the Application Launcer:
It raises the Application Launcher dialog:
Enter Chrome inside the search field and it launches the Chrome browser:
As always, I hope this helps those trying to do the same thing.
Add user as sudoer
Somebody asked why adding a user to the wheel group in didn’t enable them as a sudoer, as qualified in my earlier Fedora post. The reason is that you also need to modify the primary group in the /etc/passwd file to specify the Group ID value for the wheel group as the primary group of the designated student user.
You can identify the Group ID with the following command:
cat /etc/group | grep wheel |
It should return the following for the wheel group:
wheel:x:10:student |
You need to check the target student user in the /etc/passwd file, which you can do with the following command:
cat /etc/passwd | grep student |
It should return the following for the student user, which has a default group value equal to the user of the same name:
student:x:1000:1000:Student:/home/student:/bin/bash |
As the root user, edit the /etc/passwd file to correct the student user’s primary group ID, as follows:
student:x:1000:10:Student:/home/student:/bin/bash |
You should see the following two lines. If you want authorized sudoers to provide a password (recommended), then modify the first line by removing the # comment. If you don’t want authorized sudoers to provide a password, modify the second line by removing the # comment. Open the /etc/sudoers file with vi or gedit if you’d like a GUI editor.
# %wheel ALL=(ALL) ALL # %wheel ALL=(ALL) NOPASSWD: ALL |
Hope this helps. It’s a quick update for Fedora 30, you su to root and add your user to the sudoers list with the following syntax:
usermod someusername -a -G wheel |
By the way, don’t forget to log off and then back on to the account.
Find files with errors
My students wanted a quick solution on how to find the log files that contain errors. That’s a simple line of code in Linux if you want any Oracle errors that start with ORA-:
find $HOME/lab2 -type f | xargs grep -i ora\- |
It takes only a moment more to look for errors starting with ORA- or PLS-, like:
find $HOME/lab2 -type f | xargs grep -i -e ora\- -e pls\- |
The latter might return something like this:
contact_lab.txt:ORA-00904: "MEMBER_LAB_ID": invalid identifier contact_lab.txt:ORA-00942: table or view does not exist contact_lab.txt:ORA-00942: table or view does not exist member_lab.txt:ORA-02264: name already used by an existing constraint member_lab.txt:ORA-00955: name is already used by an existing object |
You can improve the error identification by identifying line numbers by adding -n option, like:
find $HOME/lab2 -type f | xargs grep -in -e ora\- -e pls\- |
The latter might return something like this when there are two or more files:
contact_lab.txt:76:ORA-00904: "MEMBER_LAB_ID": invalid identifier contact_lab.txt:150:ORA-00942: table or view does not exist contact_lab.txt:157:ORA-00942: table or view does not exist member_lab.txt:75:ORA-02264: name already used by an existing constraint member_lab.txt:149:ORA-00955: name is already used by an existing object |
Unfortunately, the command raises an error when there aren’t any files found of with a qualified extension. It also fails to prepend the file name when there’s only one qualified file name. As a result of these deficiencies, I’ve written the following Bash shell script. I’ve opted to call it the .findErrors.bashrc file name and deploy it in the user’s $HOME directory.
#!/bin/bash # Assign any file filter to the ext variable. ext=${1} # Assign the extension or simply use a wildcard for all files. if [ ! -z ${ext} ]; then ext="*.${ext}" else ext="*" fi # Assign the number of qualifying files to a variable. fileNum=$(ls -l ${ext} 2>/dev/null | grep -v ^l | wc -l) # Evaluate the number of qualifying files and process. if [ ${fileNum} -eq "0" ]; then echo "[0] files exist." elif [ ${fileNum} -eq "1" ]; then fileName=$(ls ${ext}) find `pwd` -type f | grep -in ${ext} -e ora\- -e pls\- | while IFS='\n' read list; do echo "${fileName}:${list}" done else find `pwd` -type f | grep -in ${ext} -e ora\- -e pls\- | while IFS='\n' read list; do echo "${list}" done fi |
You can modify the errors() function with or without a file extension to identify errors beginning with ORA- or PLS- in their log files. As always, I hope this helps those looking for a solution.
Chrome on Fedora 27
Installing Chrome wasn’t as easy just running the yum utility. You need to download it from the following website.
rpm utility to run it, you’ll get the following errors:
warning: google-chrome-stable_current_x86_64.rpm: Header V4 DSA/SHA1 Signature, key ID 7fac5991: NOKEY
error: Failed dependencies:
/usr/bin/lsb_release is needed by google-chrome-stable-74.0.3729.131-1.x86_64
libappindicator3.so.1()(64bit) is needed by google-chrome-stable-74.0.3729.131-1.x86_64
liberation-fonts is needed by google-chrome-stable-74.0.3729.131-1.x86_64 |
- lab_release
- libappindicator3.so.1
- liberation-fonts
While the error message indicates you’re missing the libappindicator3.so.1 library, the required library is actually the libappindicator-gtk3 library. You can use the yum utility to install the required library from the repository as the root user.
The library you need is actually in the repository as libappindicator-gtk3. You can use the yum utility to install the required library.
yum install -y libappindicator-gtk3 Last metadata expiration check: 1:04:24 ago on Sat 04 May 2019 05:34:34 PM MDT. Dependencies resolved. ====================================================================================================================== Package Arch Version Repository Size ====================================================================================================================== Installing: libappindicator-gtk3 x86_64 12.10.0-16.fc27 fedora 41 k Installing dependencies: libdbusmenu-gtk3 x86_64 16.04.0-4.fc27 fedora 38 k libindicator-gtk3 x86_64 12.10.1-11.fc27 fedora 67 k Transaction Summary ====================================================================================================================== Install 3 Packages Total download size: 147 k Installed size: 382 k Downloading Packages: (1/3): libdbusmenu-gtk3-16.04.0-4.fc27.x86_64.rpm 63 kB/s | 38 kB 00:00 (2/3): libappindicator-gtk3-12.10.0-16.fc27.x86_64.rpm 65 kB/s | 41 kB 00:00 (3/3): libindicator-gtk3-12.10.1-11.fc27.x86_64.rpm 93 kB/s | 67 kB 00:00 ---------------------------------------------------------------------------------------------------------------------- Total 145 kB/s | 147 kB 00:01 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : libindicator-gtk3-12.10.1-11.fc27.x86_64 1/3 Running scriptlet: libindicator-gtk3-12.10.1-11.fc27.x86_64 1/3 Installing : libdbusmenu-gtk3-16.04.0-4.fc27.x86_64 2/3 Running scriptlet: libdbusmenu-gtk3-16.04.0-4.fc27.x86_64 2/3 Installing : libappindicator-gtk3-12.10.0-16.fc27.x86_64 3/3 Running scriptlet: libappindicator-gtk3-12.10.0-16.fc27.x86_64 3/3 Verifying : libappindicator-gtk3-12.10.0-16.fc27.x86_64 1/3 Verifying : libdbusmenu-gtk3-16.04.0-4.fc27.x86_64 2/3 Verifying : libindicator-gtk3-12.10.1-11.fc27.x86_64 3/3 Installed: libappindicator-gtk3.x86_64 12.10.0-16.fc27 libdbusmenu-gtk3.x86_64 16.04.0-4.fc27 libindicator-gtk3.x86_64 12.10.1-11.fc27 Complete! |
While the error message indicates you’re missing the lab_release library, the required library is actually the redhat-lsb-core library. You can use the yum utility to install the required library from the repository as the root user.
yum install -y redhat-lsb-core Last metadata expiration check: 1:30:39 ago on Sat 04 May 2019 05:34:34 PM MDT. Dependencies resolved. ====================================================================================================================== Package Arch Version Repository Size ====================================================================================================================== Installing: redhat-lsb-core x86_64 4.1-36.fc27 fedora 42 k Installing dependencies: at x86_64 3.1.20-6.fc27 fedora 79 k mailx x86_64 12.5-25.fc27 updates 258 k ncurses-compat-libs x86_64 6.0-14.20170722.fc27 updates 321 k redhat-lsb-submod-security x86_64 4.1-36.fc27 fedora 20 k spax x86_64 1.5.3-10.fc27 fedora 212 k Transaction Summary ====================================================================================================================== Install 6 Packages Total download size: 932 k Installed size: 1.9 M Downloading Packages: (1/6): redhat-lsb-submod-security-4.1-36.fc27.x86_64.rpm 24 kB/s | 20 kB 00:00 (2/6): redhat-lsb-core-4.1-36.fc27.x86_64.rpm 48 kB/s | 42 kB 00:00 (3/6): at-3.1.20-6.fc27.x86_64.rpm 80 kB/s | 79 kB 00:00 (4/6): spax-1.5.3-10.fc27.x86_64.rpm 554 kB/s | 212 kB 00:00 (5/6): mailx-12.5-25.fc27.x86_64.rpm 1.1 MB/s | 258 kB 00:00 (6/6): ncurses-compat-libs-6.0-14.20170722.fc27.x86_64.rpm 903 kB/s | 321 kB 00:00 ---------------------------------------------------------------------------------------------------------------------- Total 479 kB/s | 932 kB 00:01 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : mailx-12.5-25.fc27.x86_64 1/6 Installing : ncurses-compat-libs-6.0-14.20170722.fc27.x86_64 2/6 Running scriptlet: ncurses-compat-libs-6.0-14.20170722.fc27.x86_64 2/6 Installing : spax-1.5.3-10.fc27.x86_64 3/6 Running scriptlet: spax-1.5.3-10.fc27.x86_64 3/6 Installing : redhat-lsb-submod-security-4.1-36.fc27.x86_64 4/6 Installing : at-3.1.20-6.fc27.x86_64 5/6 Running scriptlet: at-3.1.20-6.fc27.x86_64 5/6 Installing : redhat-lsb-core-4.1-36.fc27.x86_64 6/6 Running scriptlet: redhat-lsb-core-4.1-36.fc27.x86_64 6/6 Running as unit: run-rca25c70a677d4866bb6056b31e1034c3.service Verifying : redhat-lsb-core-4.1-36.fc27.x86_64 1/6 Verifying : at-3.1.20-6.fc27.x86_64 2/6 Verifying : redhat-lsb-submod-security-4.1-36.fc27.x86_64 3/6 Verifying : spax-1.5.3-10.fc27.x86_64 4/6 Verifying : ncurses-compat-libs-6.0-14.20170722.fc27.x86_64 5/6 Verifying : mailx-12.5-25.fc27.x86_64 6/6 Installed: redhat-lsb-core.x86_64 4.1-36.fc27 at.x86_64 3.1.20-6.fc27 mailx.x86_64 12.5-25.fc27 ncurses-compat-libs.x86_64 6.0-14.20170722.fc27 redhat-lsb-submod-security.x86_64 4.1-36.fc27 spax.x86_64 1.5.3-10.fc27 Complete! |
The last missing library is liberation-fonts, which you can also install from the repository with the yum utility, like so as the root user:
yum install -y liberation-fonts Last metadata expiration check: 2:01:27 ago on Sat 04 May 2019 05:34:34 PM MDT. Dependencies resolved. ====================================================================================================================== Package Arch Version Repository Size ====================================================================================================================== Installing: liberation-fonts noarch 1:1.07.4-10.fc27 updates 17 k Installing dependencies: liberation-narrow-fonts noarch 1:1.07.4-10.fc27 updates 208 k Transaction Summary ====================================================================================================================== Install 2 Packages Total download size: 225 k Installed size: 476 k Downloading Packages: (1/2): liberation-fonts-1.07.4-10.fc27.noarch.rpm 49 kB/s | 17 kB 00:00 (2/2): liberation-narrow-fonts-1.07.4-10.fc27.noarch.rpm 336 kB/s | 208 kB 00:00 ---------------------------------------------------------------------------------------------------------------------- Total 191 kB/s | 225 kB 00:01 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : liberation-narrow-fonts-1:1.07.4-10.fc27.noarch 1/2 Installing : liberation-fonts-1:1.07.4-10.fc27.noarch 2/2 Running scriptlet: liberation-fonts-1:1.07.4-10.fc27.noarch 2/2 Verifying : liberation-fonts-1:1.07.4-10.fc27.noarch 1/2 Verifying : liberation-narrow-fonts-1:1.07.4-10.fc27.noarch 2/2 Installed: liberation-fonts.noarch 1:1.07.4-10.fc27 liberation-narrow-fonts.noarch 1:1.07.4-10.fc27 Complete! |
You can install the Chrome browser with the following command as the root user:
yum install -y google-chrome-stable_current_x86_64.rpm Last metadata expiration check: 2:08:09 ago on Sat 04 May 2019 05:34:34 PM MDT. Dependencies resolved. ====================================================================================================================== Package Arch Version Repository Size ====================================================================================================================== Installing: google-chrome-stable x86_64 74.0.3729.131-1 @commandline 56 M Transaction Summary ====================================================================================================================== Install 1 Package Total size: 56 M Installed size: 196 M Downloading Packages: Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Running scriptlet: google-chrome-stable-74.0.3729.131-1.x86_64 1/1 Installing : google-chrome-stable-74.0.3729.131-1.x86_64 1/1 Running scriptlet: google-chrome-stable-74.0.3729.131-1.x86_64 1/1 error: can't create transaction lock on /var/lib/rpm/.rpm.lock (Resource temporarily unavailable) error: /tmp/google.sig.KSJ5OI: key 1 import failed. error: can't create transaction lock on /var/lib/rpm/.rpm.lock (Resource temporarily unavailable) error: /tmp/google.sig.KSJ5OI: key 2 import failed. Redirecting to /bin/systemctl start atd.service Running as unit: run-rcb32925ea21c401da74f536a222563ef.service Verifying : google-chrome-stable-74.0.3729.131-1.x86_64 1/1 Installed: google-chrome-stable.x86_64 74.0.3729.131-1 Complete! |
[11346:11357:0504/212207.077855:ERROR:ssl_client_socket_impl.cc(946)] handshake failed; returned -1, SSL error code 1, net_error -200 context mismatch in svga_sampler_view_destroy |
I upgraded the code in Fedora 27 because the Firefox browser wasn’t processing HTML Select tags correctly. After the upgrade of all fixes, the Firefox browser fails to let you use tabs to query other web pages. I shutdown Firefox, restarted it successfully, and took note that the liberation-fonts package was the problem. The tab processing issue occurred because I applied liberation-fonts package without restarting Firefox. Both Firefox and Chrome use the liberation-fonts package for displaying text.
You should run Chrome with the following command-line syntax to avoid the warning errors triggered by an existing bug:
google-chrome 2>/dev/null &It would display a web page, like:
I hope this helps those looking for a solution.
Python & Oracle 1
While Python is an interpreted language, Python is a very popular programming language. You may ask yourself why it is so popular? The consensus answers to why it’s so popular points to several factors. For example, Python is a robust high-level programming language that lets you:
- Get complex things done quickly
- Automate system and data integration tasks
- Solve complex analytical problems
You find Python developers throughout the enterprise. Development, release engineering, IT operations, and support teams all use Python to solve problems. Business intelligence and data scientists use Python because it’s easy to use.
Developers don’t generally write end-user applications in Python. They mostly use Python as scripting language. Python provides a simple syntax that lets developers get complex things done quickly. Python also provides you with a vast set of libraries that let you can leverage to solve problems. Those libraries often simplify how you analyze complex data or automate repetitive tasks.
This article explains how to use the Python programming language with the Oracle database. It shows you how to install and use the cx_Oracle library to query data. Part 2 will cover how you insert, update, and delete data in the Oracle database, and how you call and use PL/SQL stored functions and procedures.
The article has two parts:
- How you install and use
cx_Oraclewith the Oracle database - How you query data statically or dynamically
This audience for this article should know the basics of writing a Python program. If you’re completely new to Python, you may want to get a copy of Eric Matthes’ Python Crash Course: A Hands-On, Project-Based Introduction to Programming. More experienced developers with shell scripting backgrounds may prefer Al Sweigart’s Automate the Boring Stuff with Python.
This article uses Python 2.7, which appears to be the primary commercial version of Python in most organizations. At least, it’s what most vendors ship with Linux distros. It also happens to be the Python distro on Fedora Linux.
How you install and use cx_Oracle with the Oracle database
The first step requires that you test the current version of Python on your Operating System (OS). For the purpose of this paper, you use the student user account. The student user is in the sudoer list, which gives the account super user privileges.
You can find the Python version by opening a Terminal session and running the following command:
[student@localhost ~]$ python -V |
It displays:
Python 2.7.5 |
You can download the current version of the cx_Oracle library at the Python Software Foundation’s web site. At the time of writing, the current version of the cx_Oracle is the cx_Oracle 5.2.1 version. The cx_Oracle library is available for download as a Red Hat Package Manager (RPM) module.
You download the cx_Oracle-5.2.1-11g-py26-1.x86_64.rpm to the /tmp directory or to a sudoer-enabled user’s downloads directory. Let’s assume you download the RPM into the /tmp directory. After you download the RPM, you can install it with the yum utility with this syntax:
yum install -y /tmp/cx_Oracle-5.2.1-11g-py27-1.x86_64.rpm |
However, the most current version is now 7.0. You want the following file on Fedora 64-bit Linux, which can be found at the Python Package Index web site:
cx_Oracle-7.0.0-cp27-cp27mu-manylinux1_x86_64.whl |
A wheel file requires that you use the pip utility (make sure to upgrade to the current version), like:
sudo pip install cx_Oracle-7.0.0-cp27-cp27mu*.whl |
It should print the following to the console:
Processing ./cx_Oracle-7.0.0-cp27-cp27mu-manylinux1_x86_64.whl Installing collected packages: cx-Oracle Successfully installed cx-Oracle-7.0.0 |
The cx_Oracle library depends on the Oracle Client software, which may or may not be installed. It installs without a problem but would raise a runtime error when using the Python software. You can check whether cx_Oracle is installed with the following syntax:
rpm –qa oracle-instantclient11.2-basic |
If the oracle-instantclient11.2-basic library isn’t installed, the command returns nothing. If the oracle-instantclient11.2-basic library is installed it returns the following:
oracle-instantclient11.2-basic-11.2.0.4.0-1.x86_64 |
Assuming you don’t have the Oracle Client software installed, you should download it from Oracle’s Instant Client Downloads web page. After you download the RPM, you install the Oracle 11g Release 2 Client software with the following syntax:
yum install -y /tmp/oracle-instantclient11.2-basic-11.2.0.4.0-1.x86_64.rpm |
You now have the necessary software installed and configured to run and test Python programs that work with the Oracle database. Python uses a standard path configuration to look for Python modules or libraries. You can see that set of path values by connecting to the Python IDLE environment, which is the runtime environment. The IDLE environment is very much like the SQL*Plus environment.
You connect to the Python IDLE environment by typing the following:
python |
It opens the Python IDLE environment. It should display the following:
Python 2.7.5 (default, Apr 10 2015, 08:09:05) [GCC 4.8.3 20140911 (Red Hat 4.8.3-7)] on linux2 Type "help", "copyright", "credits" or "license" for more information. |
You import the sys library and then you can print the path elements with the following command:
>>> import sys print sys.path |
It should print the following for Python 2.7 in Fedora Linux:
['', '/usr/lib64/python27.zip', '/usr/lib64/python2.7', '/usr/lib64/python2.7/plat-linux2', '/usr/lib64/python2.7/lib-tk', '/usr/lib64/python2.7/lib-old', '/usr/lib64/python2.7/lib-dynload', '/usr/lib64/python2.7/site-packages', '/usr/lib64/python2.7/site-packages/gtk-2.0', '/usr/lib/python2.7/site-packages'] |
You can now test whether the environment works by typing the following commands in the IDLE environment:
>>> import cx_Oracle db = cx_Oracle.connect("student/student@xe") print db.version |
It prints:
11.2.0.2.0 |
The other two sections require you to test components inside Python files. That means you need to supplement the default Python path variable. You do that by adding values to the Python environment variable, which is $PYTHONPATH.
The following adds the /home/student/Code/python directory to the Python path variable:
export set PYTHONPATH=/home/student/Code/python |
Next, we create an connection.py file, which holds the following:
# Import the Oracle library. import cx_Oracle try: # Create a connection. db = cx_Oracle.connect("student/student@xe") # Print a message. print "Connected to the Oracle " + db.version + " database." except cx_Oracle.DatabaseError, e: error, = e.args print >> sys.stderr, "Oracle-Error-Code:", error.code print >> sys.stderr, "Oracle-Error-Message:", error.message finally # Close connection. db.close() |
The import statement adds the cx_Oracle library to the program scope. The cx_Oracle library’s connect function takes either the user name and password, or the user name, password, and TNS alias.
The except block differs from what you typically see. The code value maps to the SQLCODE value and the message value maps to the SQLERRM value.
You can test the connection.py file as follows in the /home/student/Code/python directory:
python connection.py |
It prints the following:
Connected to the Oracle 11.2.0.2.0 database. |
This section has shown you how to setup the cx_Oracle library, and how you can test the cx_Oracle library with Python programs.
How you query data statically or dynamically
The prior section shows you how to connect to an Oracle instance and how to verify the driver version of the cx_Oracle library. Like most ODBC and JDBC software, Python first creates a connection. Then, you need to create a cursor inside a connection.
The basicCursor.py program creates a connection and a cursor. The cursor holds a static SQL SELECT statement. The SELECT statement queries a string literal from the pseudo dual table.
# Import the Oracle library. import sys import cx_Oracle try: # Create a connection. db = cx_Oracle.connect("student/student@xe") # Create a cursor. cursor = db.cursor() # Execute a query. cursor.execute("SELECT 'Hello world!' FROM dual") # Read the contents of the cursor. for row in cursor: print (row[0]) except cx_Oracle.DatabaseError, e: error, = e.args print >> sys.stderr, "Oracle-Error-Code:", error.code print >> sys.stderr, "Oracle-Error-Message:", error.message finally: # Close cursor and connection. cursor.close() } db.close() |
The connect function assigns a database connection to the local db variable. The cursor function returns a cursor and assigns it to the local cursor variable. The execute function dispatches the query to Oracle’s SQL*Plus and returns the result set into a row element of the local cursor variable. The for-each loop reads the row element from the cursor variable and prints one row at a time. Since the cursor only returns a string literal, there’s only one row to return.
You test the program with this syntax:
python basicConnection.py |
It prints:
Hello world! |
The next basicTable.py program queries the item table. The item table holds a number of rows of data. The code returns each row inside a set of parentheses.
# Import the Oracle library. import cx_Oracle try: # Create a connection. db = cx_Oracle.connect("student/student@xe") # Create a cursor. cursor = db.cursor() # Execute a query. cursor.execute("SELECT item_title " + ", item_rating " + "FROM item " + "WHERE item_type = " " (SELECT common_lookup_id " + " FROM common_lookup " + " WHERE common_lookup_type = 'DVD_WIDE_SCREEN')") # Read the contents of the cursor. for row in cursor: print (row[0], row[1]) except cx_Oracle.DatabaseError, e: error, = e.args print >> sys.stderr, "Oracle-Error-Code:", error.code print >> sys.stderr, "Oracle-Error-Message:", error.message finally: # Close cursor and connection. cursor.close() db.close() |
The SQL query is split across several lines by using the + operator. The + operator concatenates strings, and it lets you format a long query statement. The range for loop returns tuples from the cursor. The tuples are determined by the SELECT-list of the query.
The query returns the following type of results:
('Casino Royale', 'PG-13') ... ('Star Wars - Episode I', 'PG') ('Star Wars - Episode II', 'PG') ('Star Wars - Episode III', 'PG-13') ('Star Wars - Episode IV', 'PG') ('Star Wars - Episode V', 'PG') ('Star Wars - Episode VI', 'PG') |
At this point, you know how to work with static queries. The next example shows you how to work with dynamic queries. The difference between a static and dynamic query is that an element of the string changes.
You have two options for creating dynamic strings. The first lets you glue a string inside a query. The second lets you embed one or more bind variables in a string. As a rule, you should use bind variables because they avoid SQL injection risks.
The following is the basicDynamicTable.py script
# Import the Oracle library. import cx_Oracle sRate = 'PG-13' try: # Create a connection. db = cx_Oracle.connect("student/student@xe") # Define a dynamic statment. stmt = "SELECT item_title, item_rating FROM item WHERE item_rating = :rating" # Create a cursor. cursor = db.cursor() # Execute a statement with a bind variable. cursor.execute(stmt, rating = sRate) # Read the contents of the cursor. for row in cursor: print (row[0], row[1]) except cx_Oracle.DatabaseError, e: error, = e.args print >> sys.stderr, "Oracle-Error-Code:", error.code print >> sys.stderr, "Oracle-Error-Message:", error.message finally: # Close cursor and connection. cursor.close() db.close() |
You need to assign a dynamic SQL statement to a local string variable. The bind variable is preceded with a colon (:). The execute function takes a string variable with the dynamic SQL statement. Then, you provide a name and value pair. The name needs to match the bind variable in the dynamic SQL statement. The value needs to map to a local Python variable.
The query should return a full list from the item table for the two item_title and item_rating columns:
('Casino Royale', 'PG-13')
...
('Harry Potter and the Goblet of Fire', 'PG-13')
('Harry Potter and the Order of the Phoenix', 'PG-13')
('The Lord of the Rings - Fellowship of the Ring', 'PG-13')
('The Lord of the Rings - Two Towers', 'PG-13')
('The Lord of the Rings - The Return of the King', 'PG-13')
('The Lord of the Rings - The Return of the King', 'PG-13') |
This article should have shown you how to effectively work static and dynamic queries. You can find the scripts on the github.com server.
Lab Correction
Anyone using the August 2018 Fedora image should note that I neglected to put the right transaction_upload2.csv file in the /u01/app/oracle/upload directory. You can fix that by navigating to the Lab 12 Instructions web page and click on the zip file link to download the correct file. You will see the following dialog asking whether you want to open the file with the Ark utility, click OK to continue:
After clicking OK to open in Ark, you will see the following Ark dialog:
Click on the Home option in the Places dialog to the left, then click the Downloads option. You should see the following dialog before you click the Extract button.
Open a Konsole session and become the root superuser with the following command:
su - root |
Change directory to Lab8_Final_CSV_Files directory where you extracted the transaction_upload2.csv file, like this:
cd /home/student/Downloads/Lab8_Final_CSV_Files |
Copy the transaction_upload2.csv file to the /u01/app/oracle/upload directory with the following command:
cp /home/student/Downloads/Lab8_Final_CSV_Files/transaction_upload2.csv /u01/app/oracle/upload/. |
Change directory to the /u01/app/oracle/upload directory and run the following long list (ll) command:
ll |
You should see the following:
-rw-r--r--. 1 oracle dba 80 Aug 23 22:13 character.csv drwxr-xr-x. 2 oracle dba 4096 Aug 23 20:44 preproc drwxr-xr-x. 2 oracle dba 4096 Aug 23 23:35 textfile -rw-r--r--. 1 oracle dba 128700 Dec 4 15:46 transaction_upload2.csv -rw-r--r--. 1 oracle dba 1739520 Aug 23 22:04 transaction_upload.csv |
The transaction_upload2.csv file contains a value of 3 for the created_by and last_updated_by user values. There shouldn’t be a value of 3 in the system_user_id column of the system_user table. The transaction_upload2.csv file should contain a value of 1002 for the created_by and last_updated_by user values.
You can modify the transaction_upload2.csv file once you’ve put it in the correct directory as the root user with the following command:
cat transaction_upload2.csv | sed -e 's/\,3\,/\,1002\,/g' > x; cp x transaction_upload2.csv; rm x |
The new image will correct this problem.
Preprocessing External Tables
A question that comes up now and again is there a way in Oracle Database 11g Express Edition to mimic some behavior in the Oracle Standard or Enterprise editions. Many of these questions arise because developers want to migrate a behavior they’ve implemented in Java to the Express Edition. Sometimes the answer is no but many times the answer is yes. The yes answers come with a how.
This article answers the question: “How can I read an operating systems’ file directory with out an embedded Java Virtual Machine (JVM)?” These developers have read or implemented logic like that found in my earlier “Using DBMS_JAVA to Read External Files” article. The answer is simple. You need to use a preprocessing script inside an external table. That’s what you will learn in this article, but if you’re not familiar with external tables you should read this other “External Tables” article.
External tables let you access plain text files with SQL*Loader or Oracle’s proprietary Data Pump files. You typically create external tables with Oracle Data Pump when you’re moving large data sets between database instances.
External tables use Oracle’s virtual directories. An Oracle virtual directory is an internal reference in the data dictionary. A virtual directory maps a unique directory name to a physical directory on the local operating system. Virtual directories were simple before Oracle Database 12c gave us the multitenant architecture. In a multitenant database there are two types of virtual directories. One services the schemas of the Container Database (CDB) and it’s in the CDB’s SYS schema. The other services the schemas of a Pluggable Database (PDB) and it’s in the ADMIN schema for the PDB.
You can create a CDB virtual database as SYSTEM user with the following syntax in Windows:
SQL> CREATE DIRECTORY upload AS 'C:\Data\Upload'; |
or, like this in Linux or Unix:
SQL> CREATE DIRECTORY upload AS '/u01/app/oracle'; |
There are some subtle differences between these two statements. Windows directories or folders start with a logical drive letter, like C:\, D:\, and so forth. Linux and Unix directories start with a mount point like /u01.
As you can read in the “External Tables” article, you need to change the ownership of external files and directories to the oracle user and, default, oracle user’s default dba group. Likewise, you should change the privilege of the containing directory to 755 (owner has read, write, and execute privileges; and group and others have read and execute privileges.
The balance of this article is broken into two pieces configuring a working external table with preprocessing and troubleshooting cartridge errors.
External Tables with Preprocessing Example
There are xxx database steps to creating this example. The first database step requires you create three virtual directories. The syntax for the three statements is:
SQL> CREATE DIRECTORY upload AS '/u01/app/oracle/upload'; SQL> CREATE DIRECTORY LOG AS '/u01/app/oracle/log'; SQL> CREATE DIRECTORY preproc AS '/u01/app/oracle/preproc'; |
The upload directory hosts the files you want to discover for upload. The log directory hosts the log files for the external tables. The preproc directory hosts the executable program, which generates a list of files currently in the upload directory.
After creating the virtual directories or before creating them, you should create the physical directories in the Linux operating system. The virtual directories can only point to something when it actually exists. Moreover, they work like Oracle’s synonyms that point to other objects in the database. The physical files need to be in a directory tree that is navigable by the oracle user and the oracle user and it’s default primary dba group needs to own them.
You can use the following command to change ownership when you’re the root user:
# chown –R oracle:dba /u01/app/oracle |
The second database step requires that you grant privileges on the virtual directories to the student user. You can do that with the following syntax:
SQL> GRANT read ON DIRECTORY upload; SQL> GRANT read, WRITE ON DIRECTORY LOG; SQL> GRANT read, EXECUTE ON DIRECTORY preproc; |
The upload directory requires read-only privileges. The log directory requires read and write privileges. The read privileges let it find files and the write privilege lets it append to log files when they already exist. The preproc directory requires read and execute privileges. The read privilege is the same as that explained earlier. The execute privilege lets you run the preprocessing program file.
The third database step requires creating an external file with preprocessing. The following script creates the sample table:
SQL> CREATE TABLE directory_list 2 ( file_name VARCHAR2(60)) 3 ORGANIZATION EXTERNAL 4 ( TYPE oracle_loader 5 DEFAULT DIRECTORY preproc 6 ACCESS PARAMETERS 7 ( RECORDS DELIMITED BY NEWLINE CHARACTERSET US7ASCII 8 PREPROCESSOR preproc:'list2dir.sh' 9 BADFILE 'LOG':'dir.bad' 10 DISCARDFILE 'LOG':'dir.dis' 11 LOGFILE 'LOG':'dir.log' 12 FIELDS TERMINATED BY ',' 13 OPTIONALLY ENCLOSED BY "'" 14 MISSING FIELD VALUES ARE NULL) 15 LOCATION ('list2dir.sh')) 16 REJECT LIMIT UNLIMITED; |
Line 5 designates the default directory as preproc because the location of the executable file should be in the preproc directory. Line 8 designates that there is a preprocessing step, and it identifies the virtual directory and physical file name inside single quotes. Line 15 identifies the source file for the external table, which is an executable program.
Next, you need to create the bash file to get and return a directory list. Before you write that file, you need to understand that preprocessing script files don’t inherit a $PATH environment variable from Oracle.
That probably means you might have tried to create a simple bash shell command like the following in a list2dir.sh file.
ls /u01/app/oracle/upload | find . -type f | ls *csv | sed -e 's/\.\///' |
When you test this file by calling it from SQL, like this:
SQL> SELECT * FROM directory_list; |
It raises the following exception stack:
SELECT * FROM directory_list * ERROR AT line 1: ORA-29913: error IN executing ODCIEXTTABLEFETCH callout ORA-29400: data cartridge error KUP-04095: preprocessor command /u01/app/oracle/preprocess/list2dir.sh encountered error "/u01/app/oracle/preprocess/list2dir.sh: line 1: ls: No such file or directory |
The reason isn’t immediately clear to some developers. The significant error is:
ls: No such file or directory |
The error message indicates that a call through Oracle’s OCI call interface cannot find the location of the ls program. That occurs because there is no $PATH variable set a list of values that points to the /usr/bin directory where you find the ls program. You need to prepend /usr/bin before the ls, find, and sed programs.
/usr/bin/ls /u01/app/oracle/upload | /usr/bin/find . -type f | /usr/bin/ls *csv | /usr/bin/sed -e 's/\.\///' |
Create a list2dir.sh file in the /u01/app/oracle/preproc directory with the preceding command line. Then, make sure oracle is the owner with a primary dba group and the privileges are 755 on the file. The command to set the privileges is:
# chmod –R 755 /u01/app/oracle/preproc.sh |
Having completed that Linux operating system step you should probably put some files in the upload directory. You can create empty files with the touch command at the linux command line for this example.
The fourth database step lets you query the external table, which runs the preprocessing program and returns its results as values in the table:
SQL> CREATE * FROM directory_list; |
It should return something like this:
FILE_NAME ------------------------------ character.csv transaction_upload2.csv transaction_upload.csv |
As always, this is written to help those solve problems.
MongoDB Update Statement
While discussing the pros and cons of MongoDB, my students wanted to know how to update a specific element in a collection. Collections are like tables in relational databases.
You create the users collection by inserting rows like this:
db.users.insert(
[
{ contact_account: "CA_20170321_0001"
, first_name: "Jonathan"
, middle_name: "Eoin"
, last_name: "MacGregor"
, addresses:
{
street_address: ["1111 Broadway","Suite 101"]
, city: "Oakland"
, state: "CA"
, zip: "94607"
}
}
, { contact_account: "CA_20170328_0001"
, first_name: "Remington"
, middle_name: "Alain"
, last_name: "Dennison"
, addresses:
{
street_address: ["2222 Broadway","Suite 121"]
, city: "Oakland"
, state: "CA"
, zip: "94607"
}
}
]) |
You can query the results with the db.users.find({}) command, or you can query the formatted results with the following command:
db.users.find({}).pretty() |
You can provide a simple update of middle_name element of a given collection element with the findAndModify() function. The following queries the users collection to find the JSON middle_name element where the contact_account value is equal to the “CA_20170330_0001” string.
db.users.findAndModify(
{ query: { contact_account: "CA_20170328_0001" }
, update: { $set: { middle_name: "Alan" }}
, upsert: false }) |
After changing the middle_name value from “Alain” to “Alan”, you can query the single element of the collection with the following:
db.users.find({ contact_account: "CA_20170328_0001" }).pretty() |
It should return the following:
{
"_id" : ObjectId("5bd7f69ba135dda917665de7"),
"contact_account" : "CA_20170328_0001",
"first_name" : "Remington",
"middle_name" : "Alan",
"last_name" : "Dennison",
"addresses" : {
"street_address" : [
"2222 Broadway",
"Suite 121"
],
"city" : "Oakland",
"state" : "CA",
"zip" : "94607"
}
} |
You can replace the addresses string element value a collection of elements with the following findAndModify() function:
db.users.findAndModify(
{ query: { contact_account: "CA_20170328_0001" }
, update:
{ $set:
{ addresses:
[
{
active_status: true
, start_date : new Date("2018-10-30")
, street_address: ["2222 Broadway","Suite 121"]
, city: "Oakland"
, state: "CA"
, zip: "94607"
}
, {
active_status: false
, start_date: new Date("2017-10-01")
, end_date : new Date("2018-10-29")
, street_address: ["2222 Broadway","Suite 121"]
, city: "Oakland"
, state: "CA"
, zip: "94607"
}
]
}
}
, upsert: false }) |
You can re-query the modified result set with find() function with the same query syntax as used previously. This looks for a specific member element in the collection by matching the contact_account name’s value pair. It is the same as the one used earlier in this blog post.
db.users.find({ contact_account: "CA_20170328_0001" }).pretty() |
It should return the following:
{
"_id" : ObjectId("5bd7f69ba135dda917665de7"),
"contact_account" : "CA_20170328_0001",
"first_name" : "Remington",
"middle_name" : "Alan",
"last_name" : "Dennison",
"addresses" : [
{
"active_status" : true,
"start_date" : ISODate("2018-10-30T00:00:00Z"),
"street_address" : [
"2222 Broadway",
"Suite 121"
],
"city" : "Oakland",
"state" : "CA",
"zip" : "94607"
},
{
"active_status" : false,
"start_date" : ISODate("2017-10-01T00:00:00Z"),
"end_date" : ISODate("2018-10-29T00:00:00Z"),
"street_address" : [
"2222 Broadway",
"Suite 121"
],
"city" : "Oakland",
"state" : "CA",
"zip" : "94607"
}
]
} |
As always, I hope this helps someone.
Linux mongod Service
The installation of MongoDB doesn’t do everything for you. In fact, the first time you start the mongod service, like this as the root user or sudoer user with the command:
service mongod start |
A sudoer user will be prompted for their password, like
A typical MongoDB instance raises the following errors:
Redirecting to /bin/systemctl start mongod.service [student@localhost cit425]$ mongo MongoDB shell version v3.4.11 connecting to: mongodb://127.0.0.1:27017 MongoDB server version: 3.4.11 Server has startup warnings: 2018-10-29T10:51:57.515-0600 I STORAGE [initandlisten] 2018-10-29T10:51:57.515-0600 I STORAGE [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine 2018-10-29T10:51:57.515-0600 I STORAGE [initandlisten] ** See http://dochub.mongodb.org/core/prodnotes-filesystem 2018-10-29T10:51:58.264-0600 I CONTROL [initandlisten] 2018-10-29T10:51:58.264-0600 I CONTROL [initandlisten] ** WARNING: Access control is not enabled for the database. 2018-10-29T10:51:58.264-0600 I CONTROL [initandlisten] ** Read and write access to data and configuration is unrestricted. 2018-10-29T10:51:58.264-0600 I CONTROL [initandlisten] 2018-10-29T10:51:58.265-0600 I CONTROL [initandlisten] 2018-10-29T10:51:58.265-0600 I CONTROL [initandlisten] ** WARNING: soft rlimits too low. rlimits set to 15580 processes, 64000 files. Number of processes should be at least 32000 : 0.5 times number of files. |
You can fix this by following the MongoDB instructions for the Unix ulimit Settings, which will tell you to create a mongod file in the /etc/systemd/system directory. You should create this file as the root superuser. This is what you should put in the file:
[Unit] Description=MongoDB Documentation=man:mongo [Service] # Other directives omitted # (file size) LimitFSIZE=infinity # (cpu time) LimitCPU=infinity # (virtual memory size) LimitAS=infinity # (locked-in-memory size) LimitMEMLOCK=infinity # (open files) LimitNOFILE=64000 # (processes/threads) LimitNPROC=64000 |
Then, you should be able to restart the mongod service without any warnings with this command:
service mongod restart |
As always, I hope this helps somebody.
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