My date列存储为CHAR,格式为YYYYMMDD。我必须从该列中搜索的字符串是MM/DD/YYYY格式。如何将其更改为YYYYMMDD。NULL,则不会在WHERE子句中包含道布搜索from ona where (coalesce(to_date(mnv.DOB,'YYYYMMDD'),to_date
我有一个将datatable从LINQ返回到SQL的方法 public static DataTable LinqToDataTable<T>(IEnumerable<T> source)null value cannot be assigned to a member with type System.DateTime which is a non-nullable value
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