Can't execute query

insert into web_download_count 
                           set 
                                lang_type      = 'tw', 
                                file_id        = 149,
                                p_name         = 'UNIVERSAL FIGHTING BOARD',
                                dc_id          = ,
                                dc_name        = '������',
                                IP_address     = '18.117.76.7',
                                user_device    = 0,
                                user_info      = 'Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)',
                                o_name         = 'UniversalFightingBoard_UserGuidel_20180316V1.pdf',
                                ser_name       = '1903143615.pdf',
                                sport          = 0,
                                version        = '',
                                download_type  = 1,
                                download_time  = '2024-04-19 16:01:01'

MySQL Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' dc_name = '������', ' at line 6

This script cannot continue, terminating.