Help Center/ GaussDB/ Developer Guide(Centralized_3.x)/ Application Development Guide/ Development Based on JDBC/ JDBC Package, Driver Class, and Environment Class
Updated on 2024-05-07 GMT+08:00
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JDBC Package, Driver Class, and Environment Class

JDBC Package

Obtain the package from the release package GaussDB-Kernel_Database version number_OS version number_64bit_Jdbc.tar.gz. After the decompression, you will obtain the following JDBC packages in .jar format:
  • gsjdbc4.jar: The main class name is org.postgresql.Driver, and the URL prefix of the database connection is jdbc:postgresql. This driver package applies to the scenario where services are migrated from PostgreSQL. The driver class and loading path are the same as those before the migration, but the supported APIs are different. The APIs that are not supported need to be adjusted on the service side.
  • gscejdbc.jar: The main class name is com.huawei.gaussdb.jdbc.Driver. The URL prefix of database connections is jdbc:gaussdb. This driver package contains the dependent libraries related to encryption and decryption that need to be loaded to the encrypted database. This driver package is recommended in encrypted scenarios. Currently, only EulerOS is supported. Before using the gscejdbc.jar driver package, set the environment variable LD_LIBRARY_PATH. For details, see "Setting Encrypted Equality Queries > Using JDBC to Operate an Encrypted Database" in Feature Guide.
  • opengaussjdbc.jar: The main class name is com.huawei.opengauss.jdbc.Driver. The URL prefix of the database connection is jdbc:opengauss. This driver package is recommended. This driver package is used when both PostgreSQL and GaussDB are accessed in a JVM process.
    • The loading paths and URL prefixes of driver classes vary in different driver packages, but the API functions are the same.
    • gsjdbc200.jar: The main class name is com.huawei.gauss200.jdbc.Driver, and the URL prefix of the database connection is jdbc:gaussdb. This driver package applies to the scenario where services are migrated from GaussDB 200. The driver class and loading path are the same as those before the migration, but the supported APIs are different. The APIs that are not supported need to be adjusted on the service side.
    • The gsjdbc4 driver package cannot be used to operate the PostgreSQL database. Although the connection can be successfully established in some versions, some API behaviors are different from those of PostgreSQL JDBC, which may cause unknown errors.
    • The PostgreSQL driver package cannot be used to operate GaussDB. Although the connection can be successfully established in some versions, some API behaviors are different from those of GaussDB JDBC, which may cause unknown errors.

Driver Class

Before establishing a database connection, load the org.postgresql.Driver database driver class.

  1. GaussDB is compatible with PostgreSQL in the use of JDBC. Therefore, when two JDBC drivers are used in the same process, class names may conflict.
  2. Compared with the PostgreSQL driver, the GaussDB JDBC driver has the following enhanced features:
    1. The SHA256 encryption mode is supported for login.
    2. The third-party log framework that implements the sf4j API can be connected.
    3. DR failover is supported.

Environment Class

JDK 1.8 must be configured on the client. The configuration method is as follows:

  1. Enter java -version in the MS-DOS window (command prompt in Windows) to check the JDK version. Ensure that the JDK version is JDK1.8. If JDK is not installed, download the installation package from the official website and install it.
  2. Configure system environment variables.

    1. Right-click My computer and choose Properties.
    2. In the navigation pane, choose Advanced system settings.
    3. In the System Properties dialog box, click Environment Variables on the Advanced tab page.
    4. In the System variables area of the Environment Variables dialog box, click New or Edit to configure system variables. For details, see Table 1.
      Table 1 Variables

      Variable

      Operation

      Variable Value

      JAVA_HOME
      • If the variable exists, click Edit.
      • If the variable does not exist, click New.

      Specifies the Java installation directory.

      Example: C:\Program Files\Java\jdk1.8.0_131.

      Path

      Click Edit.
      • If JAVA_HOME is configured, add %JAVA_HOME%\bin before the variable value.
      • If JAVA_HOME is not configured, add the full Java installation path before the variable value:

        C:\Program Files\Java\jdk1.8.0_131\bin

      CLASSPATH

      Click New.

      %JAVA_HOME%\lib;%JAVA_HOME%\lib\tools.jar