To query the content of a text field, you must put the expression between single quotes. The distinction between uppercase and lowercase letters depends on the database in use. LIKE, by definition, is case-sensitive (though some databases aren't so strict).
为了查询文本字段的内容，必须将表达式设置在单引号内。是否区分大小写取决于使用的数据库。按照定义，LIKE 区分大小写（尽管一些数据库并不严格区分）。