Uncaught TypeError: Cannot read property 'length' of undefined

Hello, i’ve got a table TLD in admin panel, it creating by two shortcodes, i’ve got a problem, when i start filling this table everything is good, but when this table stay realy huge i can’t save it, when i push upload button all hangs and i can’t upload it, and console start to write this error,
Uncaught TypeError: Cannot read property ‘length’ of undefined in jquery.js?ver=1.11.1:2, how can i solve this problem?