操作数类型冲突：当我尝试更新数据库时，int 与日期不兼容

Question

我正在运行此查询以更新表中的日期时间列：

DateTime today = DateTime.Today;
string[] queries = new string[] { "UPDATE *** SET ExpirationDate = " + today.ToString("yyyy/MM/dd"),
"UPDATE *** SET WrittenDate = " + today.ToString("yyyy/MM/dd"),
"UPDATE *** SET SystemDate = " + today.ToString("yyyy/MM/dd"),
"UPDATE *** SET SystemDate = " + today.ToString("yyyy/MM/dd"),
"UPDATE *** SET EventDate = " + today.ToString("yyyy/MM/dd")};

此格式基于我在此线程中找到的内容： Operand type clash: int is incompatible with date + The INSERT statement conflicted with the FOREIGN KEY constraint

但它不起作用。我知道它们是日期时间字段，因为我可以成功地对它们执行 DATEADD。我只想将这些列中的所有记录设置为当前日期，但即使尝试了所有不同的方法，我仍然会收到相同的错误。提前感谢您的帮助！

Answer 1

SQL中的DATE值必须用单引号'

我正在运行此查询以更新表中的日期时间列：

DateTime today = DateTime.Today;
string[] queries = new string[] { "UPDATE *** SET ExpirationDate = '" + today.ToString("yyyy/MM/dd") + "'",
"UPDATE *** SET WrittenDate = '" + today.ToString("yyyy/MM/dd") + "'",
"UPDATE *** SET SystemDate = '" + today.ToString("yyyy/MM/dd") + "'",
"UPDATE *** SET SystemDate = '" + today.ToString("yyyy/MM/dd") + "'",
"UPDATE *** SET EventDate = '" + today.ToString("yyyy/MM/dd") + "'"};

我不确定“yyyy/MM/dd”，我想你应该把它放在“yyyyMMdd”。