Yandex Managed Service for ClickHouse® integration with Oracle via ClickHouse® JDBC Bridge
With ClickHouse® JDBC Bridge
- Request data from an external Oracle database table using the JDBC table function
. - Use the JDBC table engine
to create tables in ClickHouse® which reference a table in an external Oracle database.
Get your cloud ready
Sign up for Yandex Cloud and create a billing account:
- Navigate to the management console
and log in to Yandex Cloud or create a new account. - On the Yandex Cloud Billing
page, make sure you have a billing account linked and it has theACTIVE
orTRIAL_ACTIVE
status. If you do not have a billing account, create one and link a cloud to it.
If you have an active billing account, you can navigate to the cloud page
Learn more about clouds and folders here.
Required paid resources
The solution support costs include:
- Fee for a Managed Service for ClickHouse® cluster: using computing resources allocated to hosts (including ZooKeeper hosts) and disk space (see Managed Service for ClickHouse® pricing).
- NAT gateway fee if public access is not enabled for cluster hosts (see Virtual Private Cloud pricing).
- Fee for using public IP addresses if public access is enabled for cluster hosts (see Virtual Private Cloud pricing).
Set up your infrastructure
-
Create a security group and configure it.
Also add a rule for outgoing traffic:
- Port range:
0-65535
- Protocol:
TCP
- Source:
CIDR
- CIDR blocks:
0.0.0.0/0
This rule allows all outgoing traffic, enabling ClickHouse® JDBC Bridge to connect to external databases including Oracle.
- Port range:
-
Create a Managed Service for ClickHouse® cluster.
When creating a cluster, specify the security group prepared earlier.
Under DBMS settings, click Settings and add the jdbcBridge option with the following parameters:
- Host: IP address of your Oracle database installation.
- Port:
9019
.
-
If you do not use public access, create a NAT gateway for the subnet you want to create your Managed Service for ClickHouse® cluster in.
Prepare the external Oracle database
Warning
In the command below, all entities created for the Oracle database are specified in uppercase according to the Oracle naming rules
-
Make sure your external Oracle database installation allows connection via ports
9019
and1521
. -
Connect to your external Oracle database installation and download the ojdbc8
JDBC driver into the/opt/drivers
directory:sudo mkdir -p /opt/drivers && \ curl -s https://repo1.maven.org/maven2/com/oracle/database/jdbc/ojdbc8/ | grep -oP '(?<=href=")[0-9][^/]+(?=/")' | sort -V | tail -n1 | xargs -I{} sudo curl -o /opt/drivers/ojdbc8-{}.jar https://repo1.maven.org/maven2/com/oracle/database/jdbc/ojdbc8/{}/ojdbc8-{}.jar
-
Install Docker Engine
. -
Run ClickHouse® JDBC Bridge:
docker run -d --name jdbc_bridge --network host -v /opt/drivers:/app/drivers clickhouse/jdbc-bridge
If your container is already running, restart it to load the new drivers to ClickHouse® JDBC Bridge:
docker container restart jdbc_bridge
-
Connect to the external Oracle database as an administrator
. For example, you can use SQL Plus if you are connecting locally:sqlplus / as sysdba
-
Switch the session to the required PDB
, e.g., toPDB1
:ALTER SESSION SET CONTAINER = PDB1;
-
Create a user named
JDBC_USER
for connection from the Managed Service for ClickHouse® cluster:CREATE USER JDBC_USER IDENTIFIED BY <user_password> DEFAULT TABLESPACE USERS TEMPORARY TABLESPACE TEMP QUOTA UNLIMITED ON USERS;
Where
<user_password>
is your password for theJDBC_USER
user.Tip
To connect to different PDBs, create a common user
by adding theC##
prefix to the username, e.g.,C##JDBC_USER
. -
Grant permissions required for ClickHouse® JDBC Bridge to run:
GRANT CONNECT, RESOURCE TO JDBC_USER;
-
Connect as the new user:
CONNECT JDBC_USER/<user_password>@<Oracle_DB_host>/PDB1;
Where:
<password>
:JDBC_USER
user password.<Oracle_DB_host>
: IP address of your Oracle database installation.
-
Create a test table named
CUSTOMERS
:CREATE TABLE CUSTOMERS ( NAME VARCHAR2(100), EMAIL VARCHAR2(100) );
-
Add the test data:
INSERT INTO CUSTOMERS (NAME, EMAIL) VALUES ('Angela Smith', 'angela@example.ru'); INSERT INTO CUSTOMERS (NAME, EMAIL) VALUES ('Bob Johnson', 'bob@example.ru'); INSERT INTO CUSTOMERS (NAME, EMAIL) VALUES ('Charlie Brown', 'charlie@example.ru'); COMMIT;
-
Make sure the data has been written:
SELECT * FROM CUSTOMERS;
Query data using the JDBC table function
-
Run a query to the external Oracle database using the JDBC table function:
SELECT * FROM jdbc('jdbc:oracle:thin:JDBC_USER/<user_password>@<Oracle_DB_host>:1521/PDB1', 'SELECT * FROM CUSTOMERS');
Where:
<password>
:JDBC_USER
user password.<Oracle_DB_host>
: IP address of your Oracle database installation.
If the query is successful, you will get data from the external Oracle database.
Create a table using the JDBC table engine
With the JDBC table engine, you can:
-
Query data via
SELECT
. -
Add new values via
INSERT INTO
with the following limitations:- The table in the Managed Service for ClickHouse® cluster database must exactly mirror the structure of the table it references.
- The only available write operation is
INSERT INTO
. You cannot useUPDATE
,DELETE
,ALTER
, or other statements to modify the existing data. - If you add new records and do not specify their values for fields with automatic generation (
DEFAULT
,GENERATED BY
,SYSDATE
, etc.), these values will not be generated.
To use the JDBC table engine:
-
Create a table with the JDBC table engine based on the table from the external Oracle database.
CREATE TABLE oracle_customers ENGINE = JDBC( 'jdbc:oracle:thin:JDBC_USER/<user_password>@<Oracle_DB_host>:1521/XEPDB1', 'JDBC_USER', 'CUSTOMERS' ) AS SELECT * FROM jdbc( 'jdbc:oracle:thin:JDBC_USER/<user_password>@<Oracle_DB_host>:1521/XEPDB1', 'JDBC_USER', 'SELECT * FROM CUSTOMERS' ) LIMIT 0;
You can also create a table specifying only some fields, but in this case you will not be able to add new values via
INSERT INTO
. -
Check the result:
SELECT * FROM oracle_customers;
-
Insert a new row:
INSERT INTO oracle_customers (NAME, EMAIL) VALUES ('Alice Wonderland', 'alice@example.ru');
ClickHouse® JDBC Bridge automatically opens and closes a transaction. You do not need to execute
COMMIT
separately. -
Check the result again and compare it with the previous output:
SELECT * FROM oracle_customers;
If the insertion was successful, you will see a new row in the returned output.
Delete the resources you created
Some resources are not free of charge. To avoid paying for them, delete the resources you no longer need:
ClickHouse® is a registered trademark of ClickHouse, Inc