2023年6月21日发(作者：)
SQLSERVER简单讲解如何建⽴数据库 SqlServer 2014----------------------------------------------------------------------------------------------------------------string connString = "server=LAPTOP-P2GH5L2U.;database=school;uid=sa;pwd=;";// connString 连接字符串 1 ->server 服务器名称 2->数据库名 3 ->uid 账号 4 密码SqlConnection 连接数据库SqlCommand 负责SQL语句执⾏和储存过程作⽤对sql或储存过程和返回结果进⾏操作对返回结果分为两类⼀、SqlDataReader 直接⼀⾏⾏读取数据集⼆、DataSet联合SqlDataAdapt来操作数据库--------------------------------------------------------------------------------------------------------------------SqlDataReader⽅式读取： SqlCommand cmd = new SqlCommand("SELECT id,name,age FROM student", sqlCnt); SqlDataReader sdr = null; sdr = eReader(); //执⾏命令对象，并⽤sdr指向结果集的第⼀条记录。 while (()) //每读取⼀条记录后，指向其下⼀条记录 { ine("id:{0},姓名:{1},年龄:{2}", sdr["id"], sdr["name"], sdr["age"]);
// ine("学号：{0},姓名：{1},性别：{2}",sdr[0],sdr[1],sdr[2]);
} (); //关闭读取器DataSet联合SqlDataAdapt⽅式 SqlDataAdapter sda = new SqlDataAdapter("SELECT id,name,age FROM student", sqlCnt); //SqlDataAdapter sda = new SqlDataAdapter(sCmd); DataSet ds = new DataSet(); (ds, "student"); int rowNum = ["Student"].; //获得数据集表student表中的⾏数 int columnNum = ["Student"].; //获得数据集表student中的列数 for (int i = 0; i < rowNum; i++) { for (int j = 0; j < columnNum; j++) { (["student"].Columns[j].ColumnName + ":" + ["student"].Rows[i][j].ToString()); } ine(); }
增加： string sql = "insert into student(name,age) VALUES(@USERNAME,@AGE)"; SqlCommand cmd = new SqlCommand(sql, sqlCnt); SqlParameter parm = new SqlParameter("@USERNAME", ); (parm); SqlParameter parm1 = new SqlParameter("@AGE", ); (parm1); int result = eNonQuery();删除： string sql = ("DELETE FROM student WHERE name='{0}';", ); SqlCommand cmd = new SqlCommand(sql, sqlCnt); eNonQuery();修改： string sql = ("update student set name='{0}' where name='{1}';", , ); SqlCommand cmd = new SqlCommand(sql, sqlCnt); int re = eNonQuery();
2023年6月21日发(作者：)
SQLSERVER简单讲解如何建⽴数据库 SqlServer 2014----------------------------------------------------------------------------------------------------------------string connString = "server=LAPTOP-P2GH5L2U.;database=school;uid=sa;pwd=;";// connString 连接字符串 1 ->server 服务器名称 2->数据库名 3 ->uid 账号 4 密码SqlConnection 连接数据库SqlCommand 负责SQL语句执⾏和储存过程作⽤对sql或储存过程和返回结果进⾏操作对返回结果分为两类⼀、SqlDataReader 直接⼀⾏⾏读取数据集⼆、DataSet联合SqlDataAdapt来操作数据库--------------------------------------------------------------------------------------------------------------------SqlDataReader⽅式读取： SqlCommand cmd = new SqlCommand("SELECT id,name,age FROM student", sqlCnt); SqlDataReader sdr = null; sdr = eReader(); //执⾏命令对象，并⽤sdr指向结果集的第⼀条记录。 while (()) //每读取⼀条记录后，指向其下⼀条记录 { ine("id:{0},姓名:{1},年龄:{2}", sdr["id"], sdr["name"], sdr["age"]);
// ine("学号：{0},姓名：{1},性别：{2}",sdr[0],sdr[1],sdr[2]);
} (); //关闭读取器DataSet联合SqlDataAdapt⽅式 SqlDataAdapter sda = new SqlDataAdapter("SELECT id,name,age FROM student", sqlCnt); //SqlDataAdapter sda = new SqlDataAdapter(sCmd); DataSet ds = new DataSet(); (ds, "student"); int rowNum = ["Student"].; //获得数据集表student表中的⾏数 int columnNum = ["Student"].; //获得数据集表student中的列数 for (int i = 0; i < rowNum; i++) { for (int j = 0; j < columnNum; j++) { (["student"].Columns[j].ColumnName + ":" + ["student"].Rows[i][j].ToString()); } ine(); }
增加： string sql = "insert into student(name,age) VALUES(@USERNAME,@AGE)"; SqlCommand cmd = new SqlCommand(sql, sqlCnt); SqlParameter parm = new SqlParameter("@USERNAME", ); (parm); SqlParameter parm1 = new SqlParameter("@AGE", ); (parm1); int result = eNonQuery();删除： string sql = ("DELETE FROM student WHERE name='{0}';", ); SqlCommand cmd = new SqlCommand(sql, sqlCnt); eNonQuery();修改： string sql = ("update student set name='{0}' where name='{1}';", , ); SqlCommand cmd = new SqlCommand(sql, sqlCnt); int re = eNonQuery();
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