SQL 手册SQL 函数字符串函数length本页总览lengthlengthdescriptionSyntaxINT length(VARCHAR str)返回字符串的字节。examplemysql> select length("abc");+---------------+| length('abc') |+---------------+| 3 |+---------------+mysql> select length("中国");+------------------+| length('中国') |+------------------+| 6 |+------------------+keywordsLENGTH