Library Version 18.1.25

Removing and Renaming Objects
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## Removing and Renaming Objects

Operations that remove or rename an environment, a database or a sequence object require care. First, operations on the same object must be serialized. For example, you cannot rename and remove a database simultaneously. Second, they cannot be performed if there are still open handles on the object. To solve the first issue, operations on the same objects are serialized explicitly by the server program. To solve the second issue, the driver APIs for these operations behave slightly differently from the Java base APIs.

In the driver APIs, each of these functions has a boolean argument `force`. If this argument is set to `true`, all handles opened on the object to be removed or renamed are automatically closed by the server, so the operation can proceed. If this argument is set to `false`, the operation is executed only if there is no open handle on the object; otherwise, the function throws a `SResourceInUseException` exception.

For example, if you want to remove a database even if someone is still using it, you can call `SEnvironment.removeDatabase` with the `force` parameter set to `true`:

    BdbServerConnection conn = ...;
    SEnvironment env = conn.openEnvironment("env", null);

    // Force the database to be deleted.
    env.removeDatabase(null, "db", null, true);

If you want to remove a database, but only when no one is using it, you can call the same function with the `force` parameter set to `false`:

    BdbServerConnection conn = ...;
    SEnvironment env = conn.openEnvironment("env", null);

    try {
        // Try to remove the database if no one is using it.
        env.removeDatabase(null, "db", null, false);
        // The database is removed successfully.
    } catch (SResourceInUseException e) {
        // Someone is still using the database and the database
        // is not removed
    }

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