Withdata Software provide some ETL (Extract-Transform-Load) tools for Oracle:
OraLoader Load TXT, CSV, TSV data to Oracle
XmlToOracle Transform XML data to Oracle
JsonToOracle Transform JSON data to Oracle
XlsToOra Extract data from Excel to Oracle
AccessToOracle Extract Access data to Oracle
DB2ToOracle Extract DB2 data to Oracle
MsSqlToOracle Extract SQL Server data to Oracle
MysqlToOracle Extract MySQL data to Oracle
PostgresToOracle Extract PostgreSQL data to Oracle
SqliteToOracle Extract SQLite data to Oracle
OracleCopier Extract data from one Oracle database to another