收到Sybase公司PowerDesigner产品的律师函后，只能改进一下思路了

   以前一直做各种各样数据库的信息化开发工作，有SQL Server 有Oracle 有DB2 有Mysql；所以一直就想着写一套代码逻辑后各种数据库上都能正常运行，虽然这个想法比较难100%实现，但是经过这些年的摸索算是得到了很多宝贵经验，并一直用PowerDesigner设计表结构后用配套的代码生成器生成代码。

   当然我们也想购买正版的 PowerDesigner 但是实在太贵了，有些买不起；最近正好收到了Sybase公司的律师函了，若再用就会吃官司了，那麻烦事情就大了；只能把所有跟Sybase公司相关的东西能卸载的全卸载了，只能忍痛割爱了；因为法律不是开玩笑的，若真在用那打了官司就必输了，直接全部卸载干净多一事情不如少一事情了。

   最近几年总是遇到各种数据库的情况也变得少了一些，经常用SQL Server的状态了，那代码生成器干脆直接从SQL Server生成就好了，省心省事了；也不搞那么大的野心什么数据库就生成了。

   第一步：选哪个数据库上生成代码？

  

  每个表都可以写好说明，这样生成代码时可以把说明带上。

  

  下面语句是获取所有表的的名字及说明的方法

  下面语句是获取表的所有列的信息的方法。

同时给有需要的附加上整理好的sql语句，希望能派上一些参考意义：

SELECT A.name AS TableName
                                         ,B.value AS Description
                                        FROM (SELECT name, id 
                                                FROM SysObjects 
                                              WHERE xType='U' AND category = 0) AS A LEFT OUTER JOIN
                                                  (SELECT major_id, value 
                                                     FROM sys.extended_properties 
                                                    WHERE name='MS_Description' 
                                                          AND minor_id = 0) AS B  ON A.id = B.major_id
                                        ORDER BY A.name

?

SELECT 表名  = CASE a.colorder WHEN 1 THEN c.name ELSE '' END,

                                       序    = a.colorder,

                                       字段名= a.name,

                                       标识  = CASE COLUMNPROPERTY(a.id,a.name,'IsIdentity') WHEN 1 THEN '√' ELSE '' END,

                                       主键  = CASE

                                  WHEN EXISTS ( SELECT * FROM sysobjects WHERE xtype='PK'

                                AND name IN (SELECT [name] FROM sysindexes   WHERE id=a.id

                                AND indid IN (SELECT indid FROM sysindexkeys WHERE id=a.id

                                AND colid IN (SELECT colid FROM syscolumns   WHERE id=a.id

                                AND name=a.name)))) THEN '√' ELSE '' END,

                                     类型= b.name,

                                     字节数= a.length,

                                     长度  = COLUMNPROPERTY(a.id,a.name,'Precision'),

                                     小数  = CASE ISNULL(COLUMNPROPERTY(a.id,a.name,'Scale'),0) WHEN 0 THEN '' ELSE CAST(COLUMNPROPERTY(a.id,a.name,'Scale') AS VARCHAR) END,

                                     允许空= CASE a.isnullable WHEN 1 THEN '√' ELSE '' END,

                                     默认值= ISNULL(d.[text],''),

                                     说明  = ISNULL(e.[value],'')

                                 FROM syscolumns a

                                LEFT JOIN systypes b ON a.xtype=b.xusertype

                                INNER JOIN sysobjects c ON a.id=c.id AND c.xtype='U' AND c.name<>'dtproperties'

                                LEFT JOIN syscomments d ON a.cdefault=d.id

                                LEFT JOIN sys.extended_properties e ON a.id = e.major_id AND a.colid=e.minor_id AND e.name='MS_Description'

                                WHERE c.name = '" + tableName + @"'

                                ORDER BY c.name, a.colorder"