操作数数据类型 ntext 对于 max 运算符无效

SoStyle.chi_description AS chi_description,

SoStyle.description AS eng_description,
SoStyle.chi_quality AS chi_quality,
SoStyle.quality_text AS quality_text

在添加以下长字段查询时，报错：不能比较或排序 text、ntext 和 image 数据类型，除非使用 IS NULL 或 LIKE 运算符

后在每个字段中加MAX();

又报错：操作数数据类型 ntext 对于 max 运算符无效

最后将其转换成

MAX(CONVERT(NVARCHAR(1000), soStyle.chi_description)) AS chi_description,
MAX(CONVERT(NVARCHAR(1000), soStyle.description)) AS eng_description,
MAX(CONVERT(NVARCHAR(1000), soStyle.chi_quality)) AS chi_quality,
MAX(CONVERT(NVARCHAR(1000), soStyle.quality_text)) AS quality_text

编译通过