/// <summary>
/// 获取表列架构（链接错误时，抛异常）
/// </summary>
/// <param name="tableName">表名</param>
/// <param name="conn">数据库链接</param>
/// <param name="errInfo">出错时的错误信息</param>
/// <returns></returns>
public static MDataColumn GetColumns(string tableName, string conn, out string errInfo)
{
errInfo = string.Empty;
DbBase helper = DalCreate.CreateDal(conn);
helper.ChangeDatabaseWithCheck(tableName);//检测dbname.dbo.tablename的情况
if (!helper.TestConn())
{
errInfo = helper.debugInfo.ToString();
if (string.IsNullOrEmpty(errInfo))
{
errInfo = "Open database fail : " + tableName;
}
helper.Dispose();
Error.Throw(errInfo);
return(null);
}
if (!tableName.Contains(" "))
{
tableName = GetMapTableName(conn, tableName);
}
MDataColumn mdc = TableSchema.GetColumns(tableName, ref helper);
helper.Dispose();
return(mdc);
}
/// <summary>
/// 获取表列架构（链接错误时，抛异常）
/// </summary>
/// <param name="tableName">表名</param>
/// <param name="conn">数据库链接</param>
/// <param name="errInfo">出错时的错误信息</param>
/// <returns></returns>
public static MDataColumn GetColumns(string tableName, string conn, out string errInfo)
{
errInfo = string.Empty;
DbBase helper = DalCreate.CreateDal(conn);
DbResetResult result = helper.ChangeDatabaseWithCheck(tableName);//检测dbname.dbo.tablename的情况
switch (result)
{
case DbResetResult.No_DBNoExists:
helper.Dispose();
return(null);
case DbResetResult.No_SaveDbName:
case DbResetResult.Yes:
tableName = SqlFormat.NotKeyword(tableName); //same database no need database.tablename
break;
}
if (!helper.TestConn(AllowConnLevel.MaterBackupSlave))
{
errInfo = helper.debugInfo.ToString();
if (string.IsNullOrEmpty(errInfo))
{
errInfo = "Open database fail : " + tableName;
}
helper.Dispose();
Error.Throw(errInfo);
return(null);
}
if (!tableName.Contains(" "))//
{
tableName = GetMapTableName(conn, tableName);
}
MDataColumn mdc = TableSchema.GetColumns(tableName, ref helper);
helper.Dispose();
return(mdc);
}
/// <summary>
/// 获取指定的表架构生成的SQL(Alter Table)语句
/// </summary>
public static List <string> AlterTableSql(string tableName, MDataColumn columns, string conn)
{
List <string> sql = new List <string>();
DbBase helper = DalCreate.CreateDal(conn);
helper.ChangeDatabaseWithCheck(tableName);//检测dbname.dbo.tablename的情况
if (!helper.TestConn())
{
helper.Dispose();
return(sql);
}
DalType dalType = helper.dalType;
string version = helper.Version;
MDataColumn dbColumn = TableSchema.GetColumns(tableName, ref helper);//获取数据库的列结构
helper.Dispose();
//开始比较异同
List <MCellStruct> primaryKeyList = new List <MCellStruct>();
string tbName = SqlFormat.Keyword(tableName, dalType);
string alterTable = "alter table " + tbName;
foreach (MCellStruct ms in columns)//遍历新的结构
{
string cName = SqlFormat.Keyword(ms.ColumnName, dalType);
if (ms.AlterOp != AlterOp.None)
{
bool isContains = dbColumn.Contains(ms.ColumnName);
if (ms.AlterOp == AlterOp.Drop)
{
#region MyRegion
if (isContains)
{
switch (dalType)
{
case DalType.MsSql:
case DalType.Access:
case DalType.MySql:
case DalType.Oracle:
if (dalType == DalType.MsSql)
{
sql.Add(@"declare @name varchar(50) select @name =b.name from sysobjects b join syscolumns a on b.id = a.cdefault
where a.id = object_id('" + tableName + "') and a.name ='" + ms.ColumnName + "'if(@name!='') begin EXEC('alter table Base_Button drop constraint '+ @name) end");
}
sql.Add(alterTable + " drop column " + cName);
break;
case DalType.Sybase:
sql.Add(alterTable + " drop " + cName);
break;
}
}
#endregion
}
else if (ms.AlterOp == AlterOp.Rename)
{
#region MyRegion
if (!string.IsNullOrEmpty(ms.OldName) && ms.OldName != ms.ColumnName && !isContains)
{
string oName = SqlFormat.Keyword(ms.OldName, dalType);
switch (dalType)
{
case DalType.MsSql:
sql.Add("exec sp_rename '" + tbName + "." + oName + "', '" + ms.ColumnName + "', 'column'");
break;
case DalType.Sybase:
sql.Add("exec sp_rename \"" + tableName + "." + ms.OldName + "\", " + ms.ColumnName);
break;
case DalType.MySql:
sql.Add(alterTable + " change " + oName + " " + GetKey(ms, dalType, ref primaryKeyList, version).TrimEnd(','));
break;
case DalType.Oracle:
sql.Add(alterTable + " rename column " + oName + " to " + cName);
break;
}
}
#endregion
}
else if (ms.AlterOp == AlterOp.AddOrModify)
{
string alterSql = SqlFormat.Keyword(ms.ColumnName, dalType) + " " + DataType.GetDataType(ms, dalType, version);
//智能判断
if (isContains) // 存在，则修改
{
//检测是否相同
MCellStruct dbStruct = dbColumn[ms.ColumnName];
if (dbStruct.IsCanNull != ms.IsCanNull || dbStruct.SqlType != ms.SqlType || dbStruct.MaxSize != ms.MaxSize || dbStruct.Scale != ms.Scale)
{
string modify = "";
switch (dalType)
{
case DalType.Oracle:
case DalType.Sybase:
modify = " modify ";
break;
case DalType.MySql:
modify = " change " + cName + " ";
break;
case DalType.MsSql:
case DalType.Access:
modify = " alter column ";
break;
}
if (ms.IsCanNull != dbStruct.IsCanNull)
{
alterSql += (ms.IsCanNull ? " NULL" : " NOT NULL");
}
sql.Add(alterTable + modify + alterSql);
}
}
else //不在，则添加
{
sql.Add(alterTable + " add " + GetKey(ms, dalType, ref primaryKeyList, version).TrimEnd(','));
if (!string.IsNullOrEmpty(ms.Description))
{
string description = SqlCreateForSchema.GetTableDescriptionSql(tableName, ms, dalType, true);
if (!string.IsNullOrEmpty(description))
{
sql.Add(description);
}
}
}
}
}
}
return(sql);
}
