Install and configure OceanBase Connector/ODBC for Linux

After you obtain the installation package of OceanBase Connector/ODBC for Linux, perform the following operations to install and configure OceanBase Connector/ODBC.

Install OceanBase Connector/ODBC

1. Check whether OceanBase Connector/ODBC is installed. If so, query its version information.

    ```bash
    rpm -qa | grep odbc
    rpm -qa | grep obclient
    ```
   

2. If you need another version, run the following commands to delete the current one.

    ```bash
    rpm -e ob-connector-odbc-<version_no>.rpm   
    rpm -e libobclient-<version_no>.rpm   
    rpm -e ob-unixodbc-<version_no>.rpm   
    ```
   

3. Install the RPM package of OceanBase Connector/ODBC of the target version.

    ```bash
    sudo rpm -ivh ob-connector-odbc-<version_no>.rpm  
    sudo rpm -ivh ob-unixodbc-<version_no>.rpm
    sudo rpm -ivh libobclient-<version_no>.rpm  
    ```
   

4. Check whether the version is correct.

    ```bash
    rpm -qa | grep odbc
    rpm -qa | grep obclient
    ```
   

Install the required Libtool based on the actual environment.

yum install libtool-ltdl-devel  

Configure environment variables

1. Put the odbc.ini configuration file in the /etc/odbc.ini directory. You can also put the file in a custom directory and set the environment variable corresponding to the file in the custom directory.

    ```bash
    $sudo vim /etc/odbc.ini
   
    [ODBC Data Sources]
    data_source_name = OBDSN
   
    [OBDSN]
    Driver=Oceanbase
    Description = OceanBase Driver DSN  
    SERVER = xxx.xxx.xxx.xxx
    PORT = 10003
    USER = tester@oracle
    Password = 1******
    Database = unittests
    OPTION = 4
    charset=UTF8
   
    [OBDSNMYSQL]
    Driver=Oceanbase
    Description = OceanBase Driver DSN  
    SERVER = xxx.xxx.xxx.xxx
    PORT = 10003
    USER = tester@sys
    Password = 1******
    Database = unittests
    OPTION = 4
    charset=UTF8
    ```
   
    The following table describes the parameters in the configuration file.
   
    | **Parameter** | **Description** |
    | --- | --- |
    | Driver | The driver in the odbcinst.ini configuration file, which can be customized.  |
    | Description | The description of the driver.  |
    | SERVER | The IP address of the database.  |
    | PORT | The port number of the database.  |
    | USER | The username to log in to the database.  |
    | Password | The password to log in to the database.  |
    | Database | The name of the database.  |
    | OPTION | The configuration option. Valid value: 4, which indicates that logging is enabled.  |
    | charset | The character set of the database. Default value: UTF8.  |
   

2. Put the odbcinst.ini configuration file in the /etc/odbcinst.ini directory.

    ```bash
    $sudo vim /etc/odbcinst.ini
   
    [Oceanbase]
    Description = ODBC for Oceanbase
    Driver = /u01/ob-connector-odbc/lib64/mariadb/libobodbc.so
    ```
   

3. Set environment variables.

    ```bash
    $export ODBCSYSINI=/etc
    $export ODBCINI=/etc/odbc.ini
    $export LD_LIBRARY_PATH=/u01/unix-odbc/lib:/u01/obclient/lib:/u01/ob-connector-odbc:$LD_LIBRARY_PATH
    ```
   

4. Run the odbcinst -j command to check whether the environment variables are correct. Example:

    ```bash
    $/u01/unix-odbc/bin/odbcinst -j
   
    unixODBC 2.3.0
    DRIVERS............: /etc/odbcinst.ini
    SYSTEM DATA SOURCES: /etc/odbc.ini
    FILE DATA SOURCES..: /etc/ODBCDataSources
    USER DATA SOURCES..: /etc/odbc.ini
    SQLULEN Size.......: 8
    SQLLEN Size........: 8
    SQLSETPOSIROW Size.: 8
    ```
   

5. Check whether the environment dependencies are correct.

    ```bash
    $cd /u01/ob-connector-odbc/lib64/mariadb
   
    [root@eefdc4281eb7 mariadb]# ldd /u01/ob-connector-odbc/lib64/mariadb/libobodbc.so
            linux-vdso.so.1 =>  (0x00007fffd4bf0000)
            libobclnt.so.20 => /u01/mysql/lib/libobclnt.so.20 (0x00007f62a8df2000)
            libodbcinst.so.2 => /u01/unix-odbc/lib/libodbcinst.so.2 (0x00007f62a8bdd000)
            libm.so.6 => /lib64/libm.so.6 (0x00007f62a88db000)
            libc.so.6 => /lib64/libc.so.6 (0x00007f62a850d000)
            libdl.so.2 => /lib64/libdl.so.2 (0x00007f62a8309000)
            libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f62a80ed000)
            libltdl.so.7 => /lib64/libltdl.so.7 (0x00007f62a7ee3000)
            /lib64/ld-linux-x86-64.so.2 (0x00007f62a92c4000)
   
    # Make sure that the dependency of libobclnt.so.20 matches the libobclient-xxx.rpm package installed.
    ```
   

Test connectivity

Test ISQL connectivity

Tools related to the driver manager are stored in the /u01/unix-odbc directory. Run the connection command and check whether the connection is successful.

$sudo vim /u01/unix-odbc/bin/isql -v OBDSN
+-------------------------------+
|  Connected!                   |
|                               |
|  sql-statement                |
|  help [tablename]             |
|  quit                         |
|                               |
+-------------------------------+
SQL>

Compile a C++ test program

g++  -I /u01/unix-odbc/include/   test.cpp  -lobodbc -o test