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Could not find the GDAL library (connection with Hana)

I am using Python 3.8.5 version and the Django 3.2.4. I already install GDAL library from the official website with the version 3.3.0. with a pip install.
There are 4 databases presents at the origin in Django but I have to use the Hana one which is notpython. I have only found 2 topics relative to that on GitHub but they are both very old (4 years and 8 years ago).
I have tried everything to solve that problem but nothing seems to work. I already have the following message when I try to make migrations :
"django.core.exceptions.ImproperlyConfigured: Could not find the GDAL library (tried "gdal302", "gdal301", "gdal300", "gdal204", "gdal203", "gdal202", "gdal201", "gdal20"). Is GDAL installed? If it is, try setting GDAL_LIBRARY_PATH in your settings."
Someone has an idea to solve that problem ?

django don't use gdal python binding. It only require the share library libgdal.so, so you need to have libgdal.so installed somewhere on your system.
Next if gdal is not installed in system directory (ie installed with your distribution package manager), django most of the time is not able to find it, even if the path is in your LD_LIBRARY_PATH.
You have to configure it explicitly in the django settings, as well as geos which is also required:
# django settings of your project
GEOS_LIBRARY_PATH = "/custom/install/prefix/lib/libgeos_c.so"
GDAL_LIBRARY_PATH = "/custom/install/prefix/lib/libgdal.so"
Take a look at https://docs.djangoproject.com/fr/3.2/ref/contrib/gis/install/geolibs/

Install PL/Python on Windows for PostgreSQL 12

I've been working on FHIR for a project and we are using PostgreSQL as a database. While reading docs, I've come to know about PL/Python and decided to give it a shot but I am unable to install the python extension.
When I run the command CREATE EXTENSION pypthon3u; I get the following error
Could not load library "C:/Program Files/PostgreSQL/12/lib/plpython3.dll": The specified module could not be found.
I've checked this SO answer but it couldn't help.
My PostgreSQL version: PostgreSQL 12.2, compiled by Visual C++ build 1914, 64-bit
Installed Python version: 3.7.7 (64 Bit)
OS Info: Windows 10 Enterprise Version 1909 OS Build 18363.657
For me, it looks like incorrect version of Python but I'm installing python 3.7.* version against which PostgreSQL is compiled as specified in doc\installation-notes.html inside the install directory.
Any help will be appreciated.

Even if you use the EDB installer's Stack Builder to install Python, you still have to follow the instructions to "ensure they are included in the PATH variable under which the database server will be started". I had to do this at the system level, as I can't find a way to set the PATH for individual services.
And then you also need to set PYTHONPATH as well, which seems to be undocumented.
So I ended up adding c:\edb\languagepack\v1\Python-3.7 to PATH and creating PYTHONPATH with c:\edb\languagepack\v1\Python-3.7\Lib.

I had to add directory containing plpython3.dll do system/user variables (windows).

I was trying the same. Though I am no expert and my errors were a bit different, here are a few things to check:
under share\extension\, there should be plpython3u.control and plpython3u--1.0.sql to be able to do CREATE EXTENSION plpython3u;
ensure you are not having any typo in the command above.
under lib\, there should be a plpython3.dll. This one is possibly created after the above step.
make sure lib\ is in your PATH.
PYTHONHOME should be set in either system/user environment, or should be set before the server start. It seems the version is not as much important as having this name set. plpython3.dll seems to look for a python39.dll but I could use it with a 3.8 installation.
I used a zipped version of Postgres, so the following is my way to run the server.
set PATH=%PATH%;d:\pgsql\bin\;d:\pgsql\lib\
set PYTHONHOME=c:\DevTools\Python\Python38
pg_ctl -D d:\pgsql\pgdata -l logfile start
PS: without PYTHONHOME, the server crashes. the server itself or psql restarts the server but I am not sure about pgAdmin.

PostgreSQL unable to create plpythonu extension

I'm trying to write a function in PostgreSQL on Windows with a Python script in the body and i'm running into an error message when trying to create the plpythonu extension. The command I'm running is:
CREATE EXTENSION plpythonu;
Which produces the following error message:
ERROR: could not access file "$libdir/plpython2": No such file or directory
SQL state: 58P01
I also tried running:
CREATE EXTENSION plpython3u;
which results in this error:
ERROR: could not load library "C:/Program Files (x86)/PostgreSQL/9.2/lib/plpython3.dll": The specified module could not be found.
SQL state: 58P01
The plpython3.dll file exists at this location, but apparently is missing some critical dependency. I've searched everywhere and found nothing helpful on this. I have both Python 2 and 3 installed on the machine...

The newest (9.4 or later) binary installations from EnterpriseDB contain only plpython3u.dll. In versions 9.4 to 9.6 I had to install python 3.3 to get plpython3u run.
You can check which version of Python is needed by plpython3u.dll using Dependency Walker.

A full answer can be found:
https://postgresrocks.enterprisedb.com/t5/PostgreSQL/unable-to-install-pl-python-extension/m-p/4090
It assumes you have used stackbuilder to install the edb language pack.
Do check the commands for correctness in your installation.
E.g. path to postgresql data, install path of edb and python version.
When you use depency walker (depends.exe), only pay attention to the pythonxx.dll. With older PG versions, this may or may not agree to the version installed by the EDB languages package. For version 10.7, version 3.4 Python is required. For windows, the later 3.4 Python versions do not appear to have a msi installer. You may have to install 3.4.4, or try to upgrade PG 10 to the latest version (10.11) first. This version requires python 3.7, so then you can use the EDB download.
But the python version may already exist and be found.
could not load library plpython3.dll (here on stackoverflow) was somewhat close, but did not detail the environment vars needed.
the solution proposed does not require you to change env vars permanently, which is a great help when using several python installations.

cx_Oracle: ImportError: DLL load failed: This application has failed

Here's what I did:
I'm on Windows XP SP3
I already had Python 2.7.1 installed.
I downloaded instantclient-basic-nt-11.2.0.3.0.zip, unzipped it, and put it in C:\Program Files\Oracle\instantclient_11_2.
I added this path to the Windows Path environment variable.
I created a new environment variable ORACLE_HOME holding this path as its value.
I installed cx_Oracle-5.1.2-11g.win32-py2.7.msi.
And on running import cx_Oracle all I get is
Traceback (most recent call last):
File "<string>", line 2, in <module>
ImportError: DLL load failed: This application has failed to start because the application configuration is incorrect. Reinstalling the application may fix this problem.
I obviously uninstalled / reinstalled cx_Oracle a couple of times but really nothing seems to help. Could anyone please provide a clue how to fix this?
UPDATE
I ran Dependency Walker and it comes up with a lot of trouble. However, the first missing .dll (msvcr80.dll) is actually present in C:\WINDOWS\WinSxS\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.91_x-ww_0de56c07.

OK, what finally solved the problem (not sure whether all steps are necessary and no idea why exactly this and only this worked so far):
Download and unzip version 12 from here.
Add "ORACLE_HOME" as a Windows environment variable and set its value to ...\instantclient_12_1, (not its containing folder!).
Add this same path to the "Path" environment variable.
Only now install cx_Oracle.

To help other people with the same problem:
This error tells about 32-64 bit mismatch between some DLL while importing module. Possibilities are:
Different architecture of Python and cx_Oracle (less probable since cx_Oracle installer on Windows warns you if appropriate Python was not found).
Different architecture of cx_Oracle libraries and oci.dll (more probable).
Keep in mind that cx_Oracle uses standart Oracle client (at OCI level), which must be installed on your machine. It searches for oci.dll in several places, including PATH. If it finds oci.dll of wrong version of the client, the error appears.
In case you get this error, check path list in the PATH environment variable. It is likely to contain path to BIN folder of wrong version of Oracle client. If you have several clients, specify in the PATH the appropriate one, or install the appropriate client.
NOTE: ORACLE_HOME does not have an effect for cx_Oracle. In my case only changing of PATH helped. I think the Ruben's solution works because of item 3 ('Add this same path to the "Path" environment variable').

I am using python35 64 bit and oracle express on win 7 (64 bit).
I installed cx_Oracle using pip3 (pip3 install cx_Oracle) instead of downloading the installer from pypi.
I faced the same problem.
I solved it by following above guidelines, but instead of 32 bit client, I downloaded the 64 bit version of the instant client (instantclient-basic-windows.x64-11.2.0.4.0.zip) from http://www.oracle.com/technetwork/topics/winx64soft-089540.html.
I then extracted it to c:\oraclexe. And added these environment variables
set ORACLE_BASE=C:\oraclexe
set ORACLE_HOME=C:\oraclexe\app\oracle\product\11.2.0\server
set PATH=C:\oraclexe\instantclient_11_2;%PATH%
And ran my django migrate commands:
python manage.py migrate
It worked excellent

Easy way:
Make sure you have installed cx-Oracle, I have cx_Oracle-5.1.3-11g.win32-py2.7.exe
Download, unzip instantclient_12_1 and move it to C:\Python27
Add environment variable C:\Python27\instantclient_12_1
Restart your computer

Same ImportError occured for setup of:
Windows 10 x64
Oracle Instant Client 12_1 x64
Python 2.7.11 x64
cx_Oracle cx_Oracle-5.2-12c.win-amd64-py2.7
I solved it copying msvcr100.dll file into <oracle_instant_client_dir>

Had this issue also, and it seems importing cx_Oracle (at least as of 5.1.2) will fail (with the same error) if you have any invalid/unreachable UNC paths in front of Oracle in the PATH environment variable.
Fixing the UNC path (which was unrelated to Oracle) resolved the problem.

If you're using conda as a package manager, one way to overcome the DLL issue it to install oracle-instantclient by doing a conda install oracle-instantclient. This fixed the dependency which I couldn't fix by manually installing Oracle's instant-client.

As is the second time I came to this question, I feel the need to post what I did:
I'm using:
Win 8 64 bits
Python 2.7
I had no success installing Python and cx_Oracle 64 bits.
It only worked when I tried 32 bits versions and followed #rob answer instructions

I had same issue with DLL load failed on my Windows machine.
installed oracle client, set variables, ran cx_Oracle-5.1.3-11g.win32-py2.7.exe file.
however when I installed cx_Oracle with easy_setup it fixed the problem.
C:\Python27\Scripts\easy_install.exe cx_Oracle-5.1.3-11g.win32-py2.7.exe

Steps I have followed :
Downloaded the smart client instantclient-basic-windows.x64-12.1.0.2.0.zip
Extracted and copied to #your directory#\instantclient_12_1
Above directory contains dll's
Append the PATH variable with #your directory#\instantclient_12_1 and created env variable ORACLE_HOME= #your directory#\instantclient_12_1
Download and install cx_Oracle-5.2.1-11g.win-amd64-py2.7.exe
Open idle type import cx_Oracle

if you're using Anaconda on Windows try:
conda install cx_oracle
on your cmd
-> this

I know this is an old post, but I had this problem today and none of the solutions worked. I figure this could work for others with the same problem as of now.
Python version : 2.7.15 (64 bits)
cx_Oracle version : 6.4.1
Oracle Instant Client : 18.3
I kept getting the following error even though I followed evry steps in the correct order :
cx_Oracle.DatabaseError: DPI-1047: Oracle Client library cannot be loaded
I solved it by downgrading my Oracle Instant Client version to 12.1

Installing python with python win32 extensions on a network drive

I need to keep a large number of Windows XP machines running the same version of python, with an assortment of modules, one of which is python-win32. I thought about installing python on a network drive that is mounted by all the client machines, and just adjust the path on the clients. Python starts up fine from the network, but when importing win32com I get a pop-up error saying:
The procedure entry point ?PyWinObject_AsHANDLE##YAHPAU_object##PAPAXH#Z could not be located in the dynamic link library pywintypes24.dll
after dismissing the message dialog I get in the console:
ImportError: DLL load failed: The specified procedure could not be found.
I searched the python directory for the pywintypes24.dll and it is present in "Lib\site-packages\pywin32_system32" .
What am I missing and is there another way in which I can install Python + Python-Win32 + additional module once and have them running on many machines? I don't have access to the Microsoft systems management tools, so I need to be a bit more low-tech than that.

On every machine you have to basically run following pywin32_postinstall.py -install once. Assuming your python installation on the network is N:\Python26, run following command on every client:
N:\Python26\python.exe N:\Python26\Scripts\pywin32_postinstall.py -install
Another important thing is Good Luck!. The reason is that you might need to do this as admin. In my case such setup worked for all but one computer. I still did not figure out why.

Python (or precisely, the OS) searches the DLLs using os.environ["PATH"] and not by searching sys.path.
So you could start Python using a simple .cmd file instead which adds \server\share\python26 to the path (given the installer (or you) copied the DLLs from \server\share\python26\lib\site-packages\pywin32-system32 to \server\share\python26).
Or, you can add the following code to your scripts before they try to import win32api etc:
# Add Python installation directory to the path,
# because on Windows 7 the pywin32 installer fails to copy
# the required DLLs to the %WINDIR%\System32 directory and
# copies them to the Python installation directory instead.
# Fortunately, in Python it is possible to modify the PATH
# before loading the DLLs.
os.environ["PATH"] = sys.prefix + ";" + os.environ.get("PATH")
import win32gui
import win32con

You could use batch files running at boot to
Mount the network share (net use \\server\share)
Copy the Python and packages installers from the network share to a local folder
Check version of the msi installer against the installed version
If different, uninstall Python and all version dependent packages
Reinstall all packages
This would be pretty much a roll your own central management system for that software.