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

This specific string is designed to be appended to a vulnerable input field (the {KEYWORD} in your example) to probe the database structure: : Closes the original string literal in the SQL query.

The primary objective of using this payload is . For a UNION operation to work, the injected query must have the exact same number of columns as the original query. This specific string is designed to be appended

If the column count is wrong (e.g., the original query has 7 or 9 columns), the database will return an error. This specific string is designed to be appended

NULL is used because it is compatible with almost any data type (string, integer, date, etc.), ensuring the query won't fail due to data type mismatches. This specific string is designed to be appended