DataTableCommon类主要是帮助取值 方法列表: public static string GetCellString(DataTable dt,int row, int column) public static string GetCellString(DataTable dt,int row, string columnName) public static int GetCellInt(DataTable dt, int row, int column) public stat
Mysql,重复字段只取其中一行 格式 : select 字段 from [表] where 其他字段 in (select 函数(其他字段) from [表] group by 相同字段) 示例如下: 从user表中,取出 user_name字段相同的记录中,id最大的那一行数据. select id,user_name from user where id in (select max(id) from user group by user_name )
public static DataTable SqlConnectionInformation() { string connstr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString; DataTable dt = new DataTable(); using (SqlConnection conn = new SqlConnection(connstr)) { if (conn