在库内查询，可用于生成如下字段结构：
[表], [字段], [数据类型], [允许为空], [主键], [外键], [引用表], [说明描述]
SELECT TOP (100) PERCENT a.name AS 表, b.name AS 字段, c.name AS 数据类型, CASE WHEN b.isnullable = 0 THEN '-' WHEN b.isnullable = 1 THEN '是' END AS 允许为空,
CASE WHEN d .name IS NULL THEN '-' WHEN d .name IS NOT NULL THEN '是' END AS 主键, CASE WHEN e.parent_object_id IS NULL THEN 0 ELSE 1 END AS 外键,
CASE WHEN e.parent_object_id IS NULL THEN '-' ELSE g.name END AS 引用表, CASE WHEN h.value IS NULL THEN '-' ELSE h.value END AS 说明描述,
i.text AS 默认值
FROM sys.sysobjects AS a INNER JOIN
sys.syscolumns AS b ON a.id = b.id INNER JOIN
sys.systypes AS c ON b.xtype = c.xtype LEFT OUTER JOIN
(SELECT so.id, sc.colid, sc.name
FROM sys.syscolumns AS sc INNER JOIN
sys.sysobjects AS so ON so.id = sc.id INNER JOIN
sys.sysindexkeys AS si ON so.id = si.id AND sc.colid = si.colid
WHERE (si.indid = 1)) AS d ON a.id = d.id AND b.colid = d.colid LEFT OUTER JOIN
sys.foreign_key_columns AS e ON a.id = e.parent_object_id AND b.colid = e.parent_column_id LEFT OUTER JOIN
sys.objects AS g ON e.referenced_object_id = g.object_id LEFT OUTER JOIN
sys.extended_properties AS h ON a.id = h.major_id AND b.colid = h.minor_id LEFT OUTER JOIN
sys.syscomments AS i ON b.cdefault = i.id
WHERE (a.type = 'U') AND (c.name <> 'sysname')
ORDER BY 表, 字段
还有一个查全库表字段的，参见另一篇 《通过(sys.sysobjects)对象表，查询全库表的基础信息 ：Sql Server 查询全库表信息》