SET PAGESIZE <num>|UNLIMITED;
Sets how many rows of text (num) there should be before column headings are repeated. By default the number of rows is set to UNLIMITED and the column headings are only displayed before the first row. If you set it to OFF, no column headings are displayed.
The following example is a table with 10 rows of data. It is set to display 10 rows before the column headings are repeated. The column headings take up one row and that leaves nine rows for table data. The table then moves to a second page with a row of header text and the remaining row of table data.