SQL2005系统升级手记之四-自动生成数据字典与系统表Sys.extended_properites

在SQL Server 2000 中，好多人都喜欢在表和列的扩展属性里面添加说明，然后用脚本生成数据库字典，升级到SQL Server 2005 后，会发现SQL Server 2000上的脚本不能使用了，其中绝大多数都是因为SQL Server 2005已经废弃了系统表 sysproperties。
注意， sysproperties 因为是无正式文档记载的系统表，已经在 Sql2005 中废弃了， Sql2005 中使用 Sys.extended_properites 保存用户自定义的表、字段的属性信息。

原先的脚本：

1 SELECT
2 ( case when a.colorder = 1 then d.name else '' end )表名,
3 a.colorder字段序号,
4 a.name字段名,
5 ( case when COLUMNPROPERTY (a.id,a.name, ' IsIdentity ' ) = 1 then ' √ ' else '' end )标识,
6 ( case when ( SELECT count ( * )
7 FROM sysobjects
8 WHERE (name in
9 ( SELECT name
10 FROM sysindexes
11 WHERE (id = a.id) AND (indid in
12 ( SELECT indid
13 FROM sysindexkeys
14 WHERE (id = a.id) AND (colid in
15 ( SELECT olid
16 FROM yscolumns
17 WHERE (id = a.id) AND (name = a.name))))))) AND
18 (xtype = ' PK ' )) > 0 then ' √ ' else '' end )主键,
19 b.name类型,
20 a.length占用字节数,
21 COLUMNPROPERTY (a.id,a.name, ' PRECISION ' ) as 长度,
22 isnull ( COLUMNPROPERTY (a.id,a.name, ' Scale ' ), 0 ) as 小数位数,
23 ( case when a.isnullable = 1 then ' √ ' else '' end )允许空,
24 isnull (e. text , '' )默认值,
25 isnull (g. [ value ] , '' ) AS 字段说明
26
27 FROM syscolumnsa left join systypesb
28 on a.xtype = b.xusertype
29 inner join sysobjectsd
30 on a.id = d.id and d.xtype = ' U ' and .name <> ' dtproperties '
31 left join syscommentse
32 on a.cdefault = e.id
33 left join syspropertiesg
34 on a.id = g.id AND a.colid = g.smallid
35 order by a.id,a.colorder

改为

1 SELECT
2 (casewhena.colorder=1thend.nameelse''end)表名,
3 a.colorder字段序号,
4 a.name字段名,
5 (casewhenCOLUMNPROPERTY(a.id,a.name,'IsIdentity')=1then'√'else''end)标识,
6 (casewhen(SELECTcount(*)
7 FROMsysobjects
8 WHERE(namein
9 (SELECTname
10 FROMsysindexes
11 WHERE(id=a.id)AND(indidin
12 (SELECTindid
13 FROMsysindexkeys
14 WHERE(id=a.id)AND(colidin
15 (SELECTcolid
16 FROMsyscolumns
17 WHERE(id=a.id)AND(name=a.name)))))))AND
18 (xtype='PK'))>0then'√'else''end)主键,
19 b.name类型,
20 a.length占用字节数,
21 COLUMNPROPERTY(a.id,a.name,'PRECISION')as长度,
22 isnull(COLUMNPROPERTY(a.id,a.name,'Scale'),0)as小数位数,
23 (casewhena.isnullable=1then'√'else''end)允许空,
24 isnull(e.text,'')默认值,
25 isnull(g.[value],'')AS字段说明
26
27 FROMsyscolumnsaleftjoinsystypesb
28 ona.xtype=b.xusertype
29 innerjoinsysobjectsd
30 ona.id=d.idandd.xtype='U'andd.name<>'dtproperties'
31 leftjoinsyscommentse
32 ona.cdefault=e.id
33leftjoinsys.extended_propertiesg
34ona.id=g.major_idANDa.colid=g.major_id
35 orderbya.id,a.colorder
36