cx_Oracle error. DPI-1047: Cannot locate a 64-bit Oracle Client library

Question

I installed the library and when trying to access SQL in jupyter notebook with my credentials the following error appears:

DatabaseError: DPI-1047: Cannot locate a 64-bit Oracle Client library: "The specified module could not be found". See https://oracle.github.io/odpi/doc/installation.html#windows for help

Answer 1

The easiest solution is as follows:

1. Download 64-bit version of oracle instantClient from: https://www.oracle.com/database/technologies/instant-client/winx64-64-downloads.html
2. Copy the dll files in the instantclient directory to the python directory, as shown below

That is it!

Answer 2

The short answer is: cx_Oracle.init_oracle_client(lib_dir= r"c:\path_to_libraries")

Here are the steps that I followed to solve this same issue:

If you have not already installed cx_Oracle you can do so with the following command:
python -m pip install cx_Oracle --upgrade

The cx_Oracle documentation can be found here .

Use the following commands to verify that everything is installed and recognized:

import sqlalchemy as sqla
import pandas as pd
import cx_Oracle

# Test to see if it will print the version of sqlalchemy
print(sqla.__version__)    # this returns 1.2.15 for me

# Test to see if the cx_Oracle is recognized
print(cx_Oracle.version)   # this returns 8.0.1 for me

# This fails for me at this point but will succeed after the solution described below
cx_Oracle.clientversion()  

At this point I get errors saying the libraries cannot be located. Here is the solution:

import os
import platform

# This is the path to the ORACLE client files
lib_dir = r"C:\put_your_path_here\instantclient-basic-windows.x64- 19.9.0.0.0dbru\instantclient_19_9"

# Diagnostic output to verify 64 bit arch and list files
print("ARCH:", platform.architecture())
print("FILES AT lib_dir:")
for name in os.listdir(lib_dir):
    print(name)

Be sure to update the lib_dir path specific to your installation. If you have the correct path, you should see a listing of all the Oracle files like: (adrci.exe, oci.dll, oci.sym, etc). This is the location that Python needs to be able to find the Oracle drivers.

The current (Nov 2020) standard way for passing the location of the Oracle libraries for Windows is cx_Oracle.init_oracle_client(lib_dir= r"c:\path_to_libraries") . Here is an example:

lib_dir = r"C:\put_your_path_here\instantclient-basic-windows.x64- 19.9.0.0.0dbru\instantclient_19_9"

try:
    cx_Oracle.init_oracle_client(lib_dir=lib_dir)
except Exception as err:
    print("Error connecting: cx_Oracle.init_oracle_client()")
    print(err);
    sys.exit(1);

At this point I can run the following code without any errors:

# This works after passing the lib_dir path
cx_Oracle.clientversion()    # For me it returns: (19, 9, 0, 0, 0)

DEPRECATED Here is how to update the PATH variable temporarily:

The following works, but using cx_Oracle.init_oracle_client(lib_dir= r"c:\path_to_libraries") is now the preferred way.

import os   
# Manually append the location of the ORACLE libraries to the PATH variable
os.environ["PATH"] = lib_dir + ";" + os.environ["PATH"]

Answer 3

As per documentation accessed on cx_Oracle page .

Step 1: install cx_Oracle

python -m pip install cx_Oracle --upgrade

Step 2: Download and extract Oracle Basic Client

For Windows download and extract Oracle Basic Instatnt client instantclient-basic-windows.x64-19.9.0.0.0dbru.zip file.

Step 3: Inform cx_Oracle module about the Instatnt Client location.

If you stick to documentation and extract them in c:\oracle folder then your script may look like this.

    import cx_Oracle
    cx_Oracle.init_oracle_client(lib_dir=r"C:\oracle\instantclient_19_9")

Now you will be free from the error.

Answer 4

I faced this error in Anconda Spyder.

This is how I fixed it.

1. Get the basic package instantClient from: https://www.oracle.com/database/technologies/instant-client/winx64-64-downloads.html

2. Extract and copy all the *.dll files and paste it to Anaconda3 folder where you have python.exe.

Answer 5

确保您已经安装了正确的 oracle 客户端（您可以从这里找到 oracle 客户端包“ https://www.oracle.com/in/database/technologies/instant-client/winx64-64-downloads.html ”并添加将下载的文件夹放在安装python的文件夹中，然后将此位置（您的客户端包文件夹的位置）添加到系统的环境变量中。希望这会起作用。

Answer 6

I suggest you to first check the compatibility of your OS, Python and Oracle Instant Client architecture:

import platform
platform.architecture()

Then, I definitely advise you to set the Oracle Instant Client inside your jupyter notebook:

import os
os.environ["PATH"] = "Complete Location of Instant Client Folder" + ";" + os.environ["PATH"]

Answer 7

For MAC

After you do : python -m pip install cx_Oracle --upgrade

try:

import cx_Oracle
# Test to see if the cx_Oracle is recognized
print(cx_Oracle.version)   # this returns 8.0.1 for me

# This fails for me at this point but will succeed after the solution described below
cx_Oracle.clientversion()  

if you encounter issues like :

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
cx_Oracle.DatabaseError: DPI-1047: Cannot locate a 64-bit Oracle Client library: "dlopen(libclntsh.dylib, 1): image not found". See https://cx-oracle.readthedocs.io/en/latest/user_guide/installation.html for help

Follow the step highlighted here: https://cx-oracle.readthedocs.io/en/latest/user_guide/installation.html#manual-installation

Manual Installation

1. Download the Basic 64-bit DMG from Oracle. ( https://www.oracle.com/database/technologies/instant-client/macos-intel-x86-downloads.html )

2. Mount the dng

3. Open the mounted dng, and run ./install_ic.sh (via terminal) eg : cd /Volumes/instantclient-basic-macos.x64-19.8.0.0.0dbru/ && ./install_ic.sh

4. In Finder, eject the mounted Instant Client package.

Re-run the oracle connection.

import cx_Oracle

cx_Oracle.init_oracle_client(lib_dir="/Users/priyank.pathak/Downloads/instantclient_19_8")
## cx_Oracle.init_oracle_client(lib_dir="/Users/your_username/Downloads/instantclient_19_8")

cx_Oracle.clientversion()  

Answer 8

Probably you have installed cx_Oracle Python library. In order to execute the DB connectivity through jupyter notebook, you need to install the Oracle Client and that is what missing in your scenario. Please follow the steps from below link and and install Oracle Client and this will solve your problem: https://oracle.github.io/odpi/doc/installation.html#windows

Answer 9

I went into the same problem but on Arch Linux , running in NodeJS . Some of the answers here helped me in searching for the official installation guide. Then I followed these steps and they worked for me: https://oracle.github.io/node-oracledb/INSTALL.html#instzip , hope it could help someone else too.

1. Download Instant Client Basic Light Package (ZIP) (Linux) https://www.oracle.com/database/technologies/instant-client/linux-x86-64-downloads.html

2. Create folder and unzip into it

   mkdir /opt/oracle unzip ~/Downloads/instantclient-basiclite-linux.x64-21.4.0.0.0dbru.zip -d /opt/oracle/

3. Then, according to the docs, execute these commands below:

   If there is no other Oracle software on the machine that will be impacted, then permanently add Instant Client to the run-time link path. For example, if the Basic package unzipped to /opt/oracle/instantclient_19_11, then run the following using sudo or as the root user

   sudo sh -c "echo /opt/oracle/instantclient_19_11 > /etc/ld.so.conf.d/oracle-instantclient.conf" sudo ldconfig

   OR

   Alternatively, every shell running Node.js will need to have the link path set:

    export LD_LIBRARY_PATH=/opt/oracle/instantclient_19_11:$LD_LIBRARY_PATH

Answer 10

This might help someone: I also had the same error and I read through the installation documentation https://cx-oracle.readthedocs.io/en/latest/user_guide/installation.html (I was using a zip for installation so I focused on section: Oracle Instant Client Zip Files)

And I was missing a "yum install -y libaio" (used 'centos:7' base image) after unzipping the oracle client to /opt/oracle and also added the following envs:

ENV ORACLE_HOME /opt/oracle/instantclient_19_3 ENV DYLD_LIBRARY_PATH /opt/oracle/instantclient_19_3 ENV LD_LIBRARY_PATH /opt/oracle/instantclient_19_3 ENV TNS_ADMIN /opt/oracle/instantclient_19_3

Answer 11

I just installed Sql Developer from Oracle and ran it for the first time, and the install added what was needed and I was able to get through that error. This was on windows. Install below, just extract it when it installs and run the .exe in the main folder. Much simpler than the other solutions!

https://www.oracle.com/database/sqldeveloper/technologies/download/

Answer 12

You just need to put the Oracle Instant Client folder in your PATH environment variable. Remember to restart whatever application that needs the instant client after updating the PATH variable.

If you installed the instant client at: c:\oracle\instantclient_21_8, simply put this folder in your PATH environment variable.

Copying the instant client files to Python folder is a very bad idea, since if you have other python versions installed in the future you will have to remember duplicating de instant client files. If you upgrade the instant client, you will need to keep these duplicated files updated too.