Esempio n. 1
0
        //删除列
        public static bool DeleteColumn(string dbname, string tableName, string colName, out string msg)
        {
            Database db  = DbFunction.GetDB(dbname);
            string   sql = string.Format("alter table {0} drop column {1} ", tableName, colName);

            msg = string.Empty;

            //检查是否存在列信息
            if (!CheckColumnExist(dbname, tableName, colName))
            {
                msg = "列" + colName + "不存在";
                return(false);
            }

            try
            {
                DbFunction.ExecuteNonQuery(dbname, sql);
                return(true);
            }
            catch (Exception ex)
            {
                msg = ex.Message;
            }
            return(false);
        }
Esempio n. 2
0
        //创建表, 检查是否在数据库里存在这个表, 如果有的话, 判断是否有数据, 有数据则不允许删除
        public static bool CreateTable(string dbname, string tableName, string Columns, string Key, out string msg)
        {
            msg = string.Empty;
            //如果已经存在就返回
            if (CheckTableExist(dbname, tableName))
            {
                msg = "表" + tableName + "已经存在";
                return(false);
            }
            var sql = string.Empty;

            if (Key.Length > 0)
            {
                sql = string.Format("create table {0}({1} CONSTRAINT PK_{0} PRIMARY KEY({2}))", tableName, Columns, Key);
            }
            else
            {
                sql = string.Format("create table {0}({1})", tableName, Columns.Remove(Columns.Length - 1));
            }
            try
            {
                DbFunction.ExecuteNonQuery(dbname, sql);
                return(true);
            }
            catch (Exception ex)
            {
                msg = ex.Message;
            }
            return(false);
        }
Esempio n. 3
0
        //修改表中的字段
        public static bool ModifyColumn(string dbname, string tableName, string colName, string colType, string colLenght, string defaultValue, string nullable, out string msg)
        {
            Database db = DbFunction.GetDB(dbname);

            msg = string.Empty;

            //检查是否存在列信息
            if (!CheckColumnExist(dbname, tableName, colName))
            {
                msg = "列" + colName + "不存在";
                return(false);
            }
            var isOraDb = db.DBType == DataBaseType.ORA;

            string sql = string.Format("alter table {0} alter column {1} ", tableName, colName);

            if (isOraDb)
            {
                sql = string.Format("alter table {0} modify ( {1} ", tableName, colName);
            }

            sql += getColTypeStr(db, colType, colLenght);
            //默认值
            if (!string.IsNullOrEmpty(defaultValue))
            {
                sql += string.Format(" default {0}", defaultValue);
            }
            //是否为空
            if (nullable == "0")
            {
                sql += " not null";
            }
            else
            {
                sql += " null";
            }
            if (isOraDb)
            {
                sql += ")";
            }
            try
            {
                DbFunction.ExecuteNonQuery(dbname, sql);
                return(true);
            }
            catch (Exception ex)
            {
                msg = ex.Message;
            }
            return(false);
        }