今天分享一个DBA和开发人员必备的神器——查询表字段属性的SQL脚本。
接手一个老项目，没有表结构文档？数据库表太多，想快速了解字段信息？写接口文档需要字段说明？这个脚本一键搞定！
一、为什么需要这个脚本？
项目交接：快速生成表结构文档
接口开发：一次性获取所有字段信息
数据库审计：检查字段属性是否规范
代码生成：自动生成实体类
问题排查：快速定位字段类型、长度
以前你可能要一个个点开表看设计，几十个表下来累死。今天这个脚本，让你秒出结果！
二、脚本代码
SELECT 表名 = CASE WHEN a.colorder = 1 THEN d.name ELSE '' END, 表说明 = CASE WHEN a.colorder = 1 THEN ISNULL(f.value, '') ELSE '' END, 字段序号 = a.colorder, 字段名 = a.name, 标识 = CASE WHEN COLUMNPROPERTY(a.id, a.name, 'IsIdentity') = 1 THEN '√' ELSE '' END, 主键 = CASE WHEN EXISTS( SELECT 1 FROM sysobjects WHERE xtype = 'PK' AND parent_obj = a.id AND name IN ( SELECT name FROM sysindexes WHERE indid IN ( SELECT indid FROM sysindexkeys WHERE id = a.id AND colid = a.colid ) ) ) THEN '√' ELSE '' END, 类型 = b.name, 占用字节数 = a.length, 长度 = COLUMNPROPERTY(a.id, a.name, 'PRECISION'), 小数位数 = ISNULL(COLUMNPROPERTY(a.id, a.name, 'Scale'), 0), 允许空 = CASE WHEN a.isnullable = 1 THEN '√' ELSE '' END, 默认值 = ISNULL(e.text, ''), 字段说明 = ISNULL(g.[value], '')FROM syscolumns aLEFT JOIN systypes b ON a.xusertype = b.xusertypeINNER JOIN sysobjects d ON a.id = d.id AND d.xtype = 'U' AND d.name <> 'dtproperties'LEFT JOIN syscomments e ON a.cdefault = e.idLEFT JOIN sysproperties g ON a.id = g.id AND a.colid = g.smallid LEFT JOIN sysproperties f ON d.id = f.id AND f.smallid = 0WHERE d.name = '要查询的表' ORDER BY a.id, a.colorder
三、怎么用？改个表名就行！
表名 表说明 字段序号 字段名 标识 主键 类型 长度 允许空 默认值 字段说明authors 1 au_id √ id 11 (无)authors 2 au_lname varchar 40 authors 3 au_fname varchar 20 authors 4 phone char 12 ('UNKNOWN')authors 5 address varchar 40 √ authors 6 city varchar 20 √ authors 7 state char 2 √ authors 8 zip char 5 √ authors 9 contract bit 1
四、字段说明怎么看？
五、实战应用场景
场景1：生成表结构文档
SELECT d.name AS 表名, a.name AS 字段名, b.name AS 类型, a.length AS 长度, CASE WHEN a.isnullable = 1 THEN '是' ELSE '否' END AS 允许空, ISNULL(g.[value], '') AS 字段说明FROM syscolumns aLEFT JOIN systypes b ON a.xusertype = b.xusertypeINNER JOIN sysobjects d ON a.id = d.id AND d.xtype = 'U' AND d.name <> 'dtproperties'LEFT JOIN sysproperties g ON a.id = g.id AND a.colid = g.smallidORDER BY d.name, a.colorder
场景2：生成实体类代码（C#）
SELECT 'public ' + CASE b.name WHEN 'int' THEN 'int' WHEN 'varchar' THEN 'string' WHEN 'nvarchar' THEN 'string' WHEN 'datetime' THEN 'DateTime' WHEN 'bit' THEN 'bool' WHEN 'decimal' THEN 'decimal' ELSE 'object' END + ' ' + a.name + ' { get; set; }' + CASE WHEN g.[value] IS NOT NULL THEN ' // ' + g.[value] ELSE '' END AS CSharpPropertyFROM syscolumns aLEFT JOIN systypes b ON a.xusertype = b.xusertypeINNER JOIN sysobjects d ON a.id = d.id AND d.name = 'authors'WHERE d.xtype = 'U'
public int au_id { get; set; } public string au_lname { get; set; } public string au_fname { get; set; } public string phone { get; set; } public string address { get; set; }
场景3：检查字段规范
SELECT d.name AS 表名, a.name AS 字段名, b.name AS 类型FROM syscolumns aLEFT JOIN systypes b ON a.xusertype = b.xusertypeINNER JOIN sysobjects d ON a.id = d.id AND d.xtype = 'U'LEFT JOIN sysproperties g ON a.id = g.id AND a.colid = g.smallidWHERE g.[value] IS NULL OR g.[value] = ''ORDER BY d.name, a.colorder
场景4：检查字段类型是否合理
SELECT d.name AS 表名, a.name AS 字段名, b.name AS 类型, a.length AS 长度FROM syscolumns aLEFT JOIN systypes b ON a.xusertype = b.xusertypeINNER JOIN sysobjects d ON a.id = d.id AND d.xtype = 'U'WHERE (a.name LIKE '%phone%' OR a.name LIKE '%tel%' OR a.name LIKE '%mobile%') AND a.length NOT IN (11, 20) ORDER BY d.name, a.colorder
场景5：对比两个表的字段差异
SELECT '表A独有' AS 类型, a.name AS 字段名, b.name AS 类型FROM (SELECT * FROM syscolumns WHERE id = OBJECT_ID('表A')) aLEFT JOIN (SELECT * FROM syscolumns WHERE id = OBJECT_ID('表B')) b ON a.name = b.nameWHERE b.name IS NULL
UNION ALL
SELECT '表B独有' AS 类型, b.name AS 字段名, b.type AS 类型FROM (SELECT * FROM syscolumns WHERE id = OBJECT_ID('表A')) aRIGHT JOIN (SELECT * FROM syscolumns WHERE id = OBJECT_ID('表B')) b ON a.name = b.nameWHERE a.name IS NULL
六、SQL Server 2005+ 增强版
SELECT 表名 = OBJECT_NAME(a.object_id), 字段序号 = a.column_id, 字段名 = a.name, 标识 = CASE WHEN a.is_identity = 1 THEN '√' ELSE '' END, 主键 = CASE WHEN EXISTS( SELECT 1 FROM sys.indexes i INNER JOIN sys.index_columns ic ON i.object_id = ic.object_id AND i.index_id = ic.index_id WHERE i.is_primary_key = 1 AND ic.column_id = a.column_id AND ic.object_id = a.object_id ) THEN '√' ELSE '' END, 类型 = t.name, 最大长度 = a.max_length, 精度 = a.precision, 小数位数 = a.scale, 允许空 = CASE WHEN a.is_nullable = 1 THEN '√' ELSE '' END, 默认值 = OBJECT_DEFINITION(a.default_object_id), 字段说明 = ISNULL(ep.value, '')FROM sys.columns aINNER JOIN sys.types t ON a.user_type_id = t.user_type_idINNER JOIN sys.objects o ON a.object_id = o.object_id AND o.type = 'U'LEFT JOIN sys.extended_properties ep ON a.object_id = ep.major_id AND a.column_id = ep.minor_id AND ep.name = 'MS_Description'WHERE o.name = '要查询的表' ORDER BY a.column_id
七、常用扩展查询
查询所有表的基本信息
SELECT 表名 = name, 创建日期 = crdate, 修改日期 = refdateFROM sysobjectsWHERE xtype = 'U'ORDER BY name
查询表的数据量
SELECT OBJECT_NAME(id) AS 表名, rows AS 记录数FROM sysindexesWHERE indid IN (0,1)ORDER BY rows DESC
综合查询：表名+字段数+数据量
SELECT o.name AS 表名, (SELECT COUNT(*) FROM syscolumns WHERE id = o.id) AS 字段数, ISNULL(i.rows, 0) AS 数据行数, o.crdate AS 创建时间FROM sysobjects oLEFT JOIN sysindexes i ON o.id = i.id AND i.indid IN (0,1)WHERE o.xtype = 'U'ORDER BY 数据行数 DESC
八、常见问题
Q：字段说明为什么是空的？
A：说明来自扩展属性，如果没有设置就是空。可以通过sp_addextendedproperty添加。
Q：怎么给字段添加说明？
A：使用系统存储过程：
EXEC sp_addextendedproperty @name = N'MS_Description', @value = N'作者ID，主键', @level0type = N'SCHEMA', @level0name = 'dbo', @level1type = N'TABLE', @level1name = 'authors', @level2type = N'COLUMN', @level2name = 'au_id'
九、总结
这个脚本的核心价值：
适用版本：
SQL Server 2000：使用第一个脚本
SQL Server 2005+：使用增强版脚本
阅读原文：原文链接
该文章在 2026/4/15 18:21:55 编辑过
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