库语句：
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* Code formatted by SoftTree SQL Assistant ?v5.0.97
* Time: 2020/3/24 8:50:02
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-- 名名称和字段名
SELECT (CASE WHEN a.colorder = 1 THEN d.name ELSE '' END) 表名,
a.colorder 字段序号,
a.name 字段名,
(
CASE
WHEN COLUMNPROPERTY(a.id, a.name, 'IsIdentity') = 1 THEN '√'
ELSE ''
END
) 标识,
(
CASE
WHEN (
SELECT COUNT(*)
FROM sysobjects
WHERE (
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))
))
))
)
AND (xtype = 'PK')
) > 0 THEN '√'
ELSE ''
END
) 主键,
b.name 类型,
a.length 占用字节数,
COLUMNPROPERTY(a.id, a.name, 'PRECISION') AS 长度,
ISNULL(COLUMNPROPERTY(a.id, a.name, 'Scale'), 0) AS 小数位数,
(CASE WHEN a.isnullable = 1 THEN '√' ELSE '' END) 允许空,
ISNULL(e.text, '') 默认值,
ISNULL(g.[value], '') AS 字段说明
FROM syscolumns a
LEFT JOIN systypes b
ON a.xtype = b.xusertype
INNER JOIN sysobjects d
ON a.id = d.id
AND d.xtype = 'U'
AND d.name <> 'dtproperties'
LEFT JOIN syscomments e
ON a.cdefault = e.id
LEFT JOIN sys.extended_properties g
ON a.id = g.major_id
AND a.colid = g.minor_id
ORDER BY
a.id,
a.colorder
表语句：
------sqlserver 查询某个表的列名称、说明、备注、类型等
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 a
left join
systypes b
on
a.xusertype=b.xusertype
inner join
sysobjects d
on
a.id=d.id and d.xtype='U' and d.name<>'dtproperties'
left join
syscomments e
on
a.cdefault=e.id
left join
sys.extended_properties g
on
a.id=G.major_id and a.colid=g.minor_id
left join
sys.extended_properties f
on
d.id=f.major_id and f.minor_id=0
where
d.name='Sys_User' --如果只查询指定表,加上此where条件，tablename是要查询的表名；去除where条件查询所有的表信息
order by
a.id,a.colorderinformation_schema：系统视图
sys.extended_properties：系统视图
表或表字段等的注释，是数据库对象的扩展属性。在MSSQL中，支持把一些注释性的内容放到数据库或数据库对象中，增强可读性，有助于日后的管理和维护工作。扩展属性的内容可以通过SSMS添加、修改或删除，也可以通过系统视图查询，通过执行相关的存储过程来维护。
1. 查询一个表的所有列名
------查询一个表的所有列名
Select Name FROM SysColumns Where id=Object_Id('Sys_User')
select t.column_name from information_schema.columns t where t.table_name='Sys_User';
如图所示:
2. 查询一个表的所有字段的注释
------查询一个表的所有字段的注释
select value from sys.extended_properties where major_id = object_id ('Sys_User' );
如图所示：
3. 查询一个表的所有列名，字段的注释
------查询一个表的所有列名，字段的注释
SELECT
A.name AS table_name,
B.name AS column_name,
C.value AS column_description
FROM sys.tables A
INNER JOIN sys.columns B ON B.object_id = A.object_id
LEFT JOIN sys.extended_properties C ON C.major_id = B.object_id AND C.minor_id = B.column_id
WHERE A.name = 'Sys_User'
如图所示：
4. 查询一个表的所有列名，数据类型
------查询一个表的所有列名，数据类型
select column_name,data_type from information_schema.columns
where table_name = 'Sys_User'
如图所示：
5. 查询一个表的所有信息
------查询一个表的所有信息
select * FROM information_schema.columns
where table_name = 'Sys_User'
6. sqlserver 查询某个表的列名称、说明、备注、类型等
------sqlserver 查询某个表的列名称、说明、备注、类型等
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 a
left join
systypes b
on
a.xusertype=b.xusertype
inner join
sysobjects d
on
a.id=d.id and d.xtype='U' and d.name<>'dtproperties'
left join
syscomments e
on
a.cdefault=e.id
left join
sys.extended_properties g
on
a.id=G.major_id and a.colid=g.minor_id
left join
sys.extended_properties f
on
d.id=f.major_id and f.minor_id=0
where
d.name='Sys_User' --如果只查询指定表,加上此where条件，tablename是要查询的表名；去除where条件查询所有的表信息
order by
a.id,a.colorder