If you're using SQLDeveloper, you can copy and paste multiple rows into a table in one operation, which makes it easy to load small amounts of data into a database for testing.
- Create your tabular data in Excel.
- Copy your data into the clipboard.
- In SQLDeveloper, open the Data tab of the required table.
- Add as many rows as required by repeatedly pressing the Insert Row button.
- Paste your data into SQLDeveloper.
If you look in the SQLDeveloper console page, you can see a sequence of INSERT statements followed by a COMMIT statement.
It seems that you can only insert a row if your database server supports transactions, so this trick works for Oracle but not for MySQL.