# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/\bVALUES\s*\((\s*(?:N'[^']*'|\w+))(?:,(?1)){12}\K,(?1)/<WHATEVER_YOU_NEED>/gm;t' <<< "INSERT member (member, prename, name, street, postalcode, town, tel1, tel2, fax, bem, anrede, salutation, email, name2, name3, association, project) VALUES (2005, N'John', N'Doe', N'Street 4711', N'1234', N'Town', N'1234-5678', N'1234-5678', N'1234-5678', N'Leader', NULL, N'Dear Mr. Doe', N'a@b.com', N'This is the text i want to delete', N'Name2', N'Name3', NULL, NULL);```"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html