{keyword}' Union All Select Null,null,null,null,null,null,null,null-- Jynz -

: Appends a new set of results to the original query's output.

: Attempts to select 8 columns of "null" data. : Appends a new set of results to

The payload you provided, ' UNION ALL SELECT NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL-- , is a common pattern used in to determine the number of columns returned by an original database query. What this Payload Does ' UNION ALL SELECT NULL