关于实时搜索字段中的安全性的问题

This is an odd question. I have a friend who is working on an application. There is a table with 4 fields that holds a word and a definition among some other things. On a website there is a textbox in which a user can enter a string and the database is queried and looks for similar content while the string is being entered in the box. (A live search sort of thing). This is an odd question. I have a friend who is