Heterogeneous Services supports callback links.

This enables SQL statements like the following to be executed:

INSERT INTO table_name@dblink SELECT column_list FROM table_name;

Even though Heterogeneous Services supports the callback functionality, not all gateways have implemented it. If the gateway that you are using has not implemented this functionality, the preceding INSERT statement returns the following error message:

ORA-02025: All tables in the SQL statement must be at the remote database

For gateways that do not support callback links, you can use the SQL*Plus COPY command. The syntax is as follows:

COPY FROM username@db_name -
   INSERT destination_table -
   USING query;

The following example selects all rows from the local Oracle emp table, inserts them into the emp table on the non-Oracle database, and commits the transaction:

COPY FROM SCOTT@inst1 -
  INSERT EMP@remote_db -
  USING SELECT * FROM EMP;

The COPY command supports the APPEND, CREATE, INSERT, and REPLACE options. However, INSERT is the only option supported when copying to non-Oracle databases. The SQL*Plus COPY command does not support copying to tables with lowercase table names. Use the following PL/SQL syntax with lowercase table names:

DECLARE
    v1 oracle_table.column1%TYPE;
    v2 oracle_table.column2%TYPE;
    v3 oracle_table.column3%TYPE;
    .
    .
    .
    CURSOR cursor_name IS SELECT * FROM oracle_table;
BEGIN
    OPEN cursor_name;
    LOOP
       FETCH cursor_name INTO v1, v2, v3, ... ;
       EXIT WHEN cursor_name%NOTFOUND;
       INSERT INTO destination_table VALUES (v1, v2, v3, ...);
    END LOOP;

    CLOSE cursor_name;
END;