---
title: ""
url: "https://docs.yugabyte.com/stable/yugabyte-voyager/migrate/oracle/"
---

# 

Create a role and a database user, and provide the user with READ access to all the resources which need to be migrated.

1. Create a role that has the privileges as listed in the following table:
   
   | Permission | Object type in the source schema                                   |
   |------------|--------------------------------------------------------------------|
   | `SELECT`   | VIEW, SEQUENCE, TABLE PARTITION, TABLE, SYNONYM, MATERIALIZED VIEW |
   | `EXECUTE`  | TYPE                                                               |
   
   Change the `<SCHEMA_NAME>` appropriately in the following snippets, and run the following steps as a privileged user.
   
   ```sql
   CREATE ROLE <SCHEMA_NAME>_reader_role;
   
   BEGIN
       FOR R IN (SELECT owner, object_name FROM all_objects WHERE owner=UPPER('<SCHEMA_NAME>') and object_type in ('VIEW','SEQUENCE','TABLE PARTITION','SYNONYM','MATERIALIZED VIEW'))
       LOOP
          EXECUTE IMMEDIATE 'grant select on '||R.owner||'."'||R.object_name||'" to <SCHEMA_NAME>_reader_role';
       END LOOP;
   END;
   /
   
   BEGIN
       FOR R IN (SELECT owner, object_name FROM all_objects WHERE owner=UPPER('<SCHEMA_NAME>') and object_type ='TABLE' MINUS SELECT owner, table_name from all_nested_tables where owner = UPPER('<SCHEMA_NAME>'))
       LOOP
          EXECUTE IMMEDIATE 'grant select on '||R.owner||'."'||R.object_name||'" to  <SCHEMA_NAME>_reader_role';
       END LOOP;
   END;
   /
   
   BEGIN
       FOR R IN (SELECT owner, object_name FROM all_objects WHERE owner=UPPER('<SCHEMA_NAME>') and object_type = 'TYPE')
       LOOP
          EXECUTE IMMEDIATE 'grant execute on '||R.owner||'."'||R.object_name||'" to <SCHEMA_NAME>_reader_role';
       END LOOP;
   END;
   /
   
   GRANT SELECT_CATALOG_ROLE TO <SCHEMA_NAME>_reader_role;
   GRANT SELECT ANY DICTIONARY TO <SCHEMA_NAME>_reader_role;
   GRANT SELECT ON SYS.ARGUMENT$ TO <SCHEMA_NAME>_reader_role;
   ```
2. Create a user `ybvoyager` and grant `CONNECT` and `<SCHEMA_NAME>_reader_role` to the user:
   
   ```sql
   CREATE USER ybvoyager IDENTIFIED BY password;
   GRANT CONNECT TO ybvoyager;
   GRANT <SCHEMA_NAME>_reader_role TO ybvoyager;
   ```
   
   If you're using [accelerated data export](#accelerate-data-export-for-mysql-and-oracle "accelerated data export"), run the additional grant as follows:
   
   ```sql
   GRANT FLASHBACK ANY TABLE TO ybvoyager;
   ```
3. If you're using [accelerated data export](#accelerate-data-export-for-mysql-and-oracle "accelerated data export"), the `log_mode` should be archivelog.
   
   1. Check the value for `log_mode` using the following command for Oracle/Oracle RDS:
      
      ```sql
      SELECT LOG_MODE FROM V$DATABASE;
      ```
   2. If the `log_mode` value is `NOARCHIVELOG`, run the following commands:
      
      **For Oracle**
      
      ```sql
      sqlplus /nolog
      SQL>alter system set db_recovery_file_dest_size = 10G;
      SQL>alter system set db_recovery_file_dest = '<oracle_path>/oradata/recovery_area' scope=spfile;
      SQL> connect / as sysdba
      SQL> Shutdown immediate
      SQL> Startup mount
      SQL> Alter database archivelog;
      SQL> Alter database open;
      ```
      
      **For Oracle RDS**
      
      **Note** that the following step assumes you're using SQL\*Plus or a compatible Oracle client that supports `EXEC`. If your client doesn't support `EXEC`, use the standard SQL CALL syntax instead.
      
      ```sql
      exec rdsadmin.rdsadmin_util.set_configuration('archivelog retention hours',24);
      ```
   3. Verify using `archive log list`.

If you want yb-voyager to connect to the source database over SSL, refer to [SSL Connectivity](/stable/yugabyte-voyager/reference/yb-voyager-cli/#ssl-connectivity "SSL Connectivity"). Note that you can use only one of the following arguments when connecting to your Oracle instance:

| [Configuration file](#set-up-a-configuration-file "Configuration file") source parameter | CLI Flag           | Description                                                                                            |
|------------------------------------------------------------------------------------------|--------------------|--------------------------------------------------------------------------------------------------------|
| db-schema                                                                                | --source-db-schema | Schema name of the source database.                                                                    |
| oracle-db-sid                                                                            | --oracle-db-sid    | Oracle System Identifier you can use while exporting data from Oracle instances.                       |
| oracle-tns-alias                                                                         | --oracle-tns-alias | TNS (Transparent Network Substrate) alias configured to establish a secure connection with the server. |