SQL 服务器查询以获取表中的列列表以及数据类型、NOT NULL 和 PRIMARY KEY 约束
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【中文标题】SQL 服务器查询以获取表中的列列表以及数据类型、NOT NULL 和 PRIMARY KEY 约束【英文标题】：SQL server query to get the list of columns in a table along with Data types, NOT NULL, and PRIMARY KEY constraints 【发布时间】：2011-01-25 23:41:36 【问题描述】：我需要在 SQL 服务器上编写一个查询来获取特定表中的列列表、其关联的数据类型（带长度）以及它们是否不为空。我已经成功地做到了这一点。
但是现在我还需要在同一个表中针对一个列 - TRUE 如果该列是主键。
我该怎么做？
我的预期输出是：
Column name | Data type | Length | isnull | Pk
【问题讨论】：
你能显示你已经拥有的代码吗？ 【参考方案1】：为避免某些列出现重复行，请使用 user_type_id 而不是 system_type_id。
SELECT
c.name 'Column Name',
t.Name 'Data type',
c.max_length 'Max Length',
c.precision ,
c.scale ,
c.is_nullable,
ISNULL(i.is_primary_key, 0) 'Primary Key'
FROM
sys.columns c
INNER JOIN
sys.types t ON c.user_type_id = t.user_type_id
LEFT OUTER JOIN
sys.index_columns ic ON ic.object_id = c.object_id AND ic.column_id = c.column_id
LEFT OUTER JOIN
sys.indexes i ON ic.object_id = i.object_id AND ic.index_id = i.index_id
WHERE
c.object_id = OBJECT_ID('YourTableName')
只需将YourTableName 替换为您的实际表名 - 适用于 SQL Server 2005 及更高版本。
如果您使用的是架构，请将YourTableName 替换为YourSchemaName.YourTableName，其中YourSchemaName 是实际架构名称，YourTableName 是实际表名称。
【讨论】：
这为 nvarchar 等类型的列提供了错误的长度。它给出的字节长度是列类型长度的两倍。 那些长度没有错 - 它确实给出了字节长度 - 这是最大可能的字节长度......如果你想计算空间等，那就是长度你想得到.... 非常适合我 SQL Server 2012 :) WHERE c.object_id = OBJECT_ID('YourTableName') .... 我需要 WHERE c.object_id = OBJECT_ID('MySchema.MyTableName') 然后一切正常。 如果您有多个索引涉及同一列，则此查询将返回重复的列。要修复它，请将最后两个连接替换为以下内容：LEFT OUTER JOIN sys.index_columns ic LEFT OUTER JOIN sys.indexes i ON ic.object_id = i.object_id AND ic.index_id = i.index_id ON ic.object_id = c.object_id AND ic.column_id = c.column_id AND i.is_primary_key=1【参考方案2】：
存储过程 sp_columns 返回详细的表信息。
exec sp_columns MyTable
【讨论】：
exec sp_pkeys exec sp_fkeys 如果使用这个，请注意MyTable 实际上只是表名，而不是模式。要过滤到架构，请将其添加为第二个参数：exec sp_columns 'MyTable', 'MySchema'【参考方案3】：
您可以使用查询：
select COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH,
NUMERIC_PRECISION, DATETIME_PRECISION,
IS_NULLABLE
from INFORMATION_SCHEMA.COLUMNS
where TABLE_NAME='TableName'
获取您需要的所有元数据，除了 Pk 信息。
【讨论】：
我做到了 :) 但我也需要 PK :| msdn.microsoft.com/pt-br/library/ms189813(v=sql.120).aspx sp_fkeys sp_pkeys【参考方案4】：在 SQL 2012 中，您可以使用：
EXEC sp_describe_first_result_set N'SELECT * FROM [TableName]'
这将为您提供列名及其属性。
【讨论】：
这适用于使用 OPENROWSET 打开的 Excel 文件，而许多其他解决方案则不能。谢谢。【参考方案5】：试试这个：
select COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH, IS_NULLABLE
from INFORMATION_SCHEMA.COLUMNS IC
where TABLE_NAME = 'tablename' and COLUMN_NAME = 'columnname'
【讨论】：
您的答案与 Ajadex 发布的答案有何不同？两个答案都不返回主键信息。【参考方案6】：为确保获得正确的长度，您需要将 unicode 类型视为一种特殊情况。请参阅下面的代码。
更多信息请见：https://msdn.microsoft.com/en-us/library/ms176106.aspx
SELECT
c.name 'Column Name',
t.name,
t.name +
CASE WHEN t.name IN ('char', 'varchar','nchar','nvarchar') THEN '('+
CASE WHEN c.max_length=-1 THEN 'MAX'
ELSE CONVERT(VARCHAR(4),
CASE WHEN t.name IN ('nchar','nvarchar')
THEN c.max_length/2 ELSE c.max_length END )
END +')'
WHEN t.name IN ('decimal','numeric')
THEN '('+ CONVERT(VARCHAR(4),c.precision)+','
+ CONVERT(VARCHAR(4),c.Scale)+')'
ELSE '' END
as "DDL name",
c.max_length 'Max Length in Bytes',
c.precision ,
c.scale ,
c.is_nullable,
ISNULL(i.is_primary_key, 0) 'Primary Key'
FROM
sys.columns c
INNER JOIN
sys.types t ON c.user_type_id = t.user_type_id
LEFT OUTER JOIN
sys.index_columns ic ON ic.object_id = c.object_id AND ic.column_id = c.column_id
LEFT OUTER JOIN
sys.indexes i ON ic.object_id = i.object_id AND ic.index_id = i.index_id
WHERE
c.object_id = OBJECT_ID('YourTableName')
【讨论】：
DDL 名称对于创建表的动态 sql 非常有用！谢谢！！【参考方案7】：扩展亚历克斯的答案，您可以这样做以获得 PK 约束
Select C.COLUMN_NAME, C.DATA_TYPE, C.CHARACTER_MAXIMUM_LENGTH, C.NUMERIC_PRECISION, C.IS_NULLABLE, TC.CONSTRAINT_NAME
From INFORMATION_SCHEMA.COLUMNS As C
Left Join INFORMATION_SCHEMA.TABLE_CONSTRAINTS As TC
On TC.TABLE_SCHEMA = C.TABLE_SCHEMA
And TC.TABLE_NAME = C.TABLE_NAME
And TC.CONSTRAINT_TYPE = 'PRIMARY KEY'
Where C.TABLE_NAME = 'Table'
我一定错过了您想要一个标志来确定给定列是否是 PK 的一部分而不是 PK 约束的名称。为此，您将使用：
Select C.COLUMN_NAME, C.DATA_TYPE, C.CHARACTER_MAXIMUM_LENGTH
, C.NUMERIC_PRECISION, C.NUMERIC_SCALE
, C.IS_NULLABLE
, Case When Z.CONSTRAINT_NAME Is Null Then 0 Else 1 End As IsPartOfPrimaryKey
From INFORMATION_SCHEMA.COLUMNS As C
Outer Apply (
Select CCU.CONSTRAINT_NAME
From INFORMATION_SCHEMA.TABLE_CONSTRAINTS As TC
Join INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE As CCU
On CCU.CONSTRAINT_NAME = TC.CONSTRAINT_NAME
Where TC.TABLE_SCHEMA = C.TABLE_SCHEMA
And TC.TABLE_NAME = C.TABLE_NAME
And TC.CONSTRAINT_TYPE = 'PRIMARY KEY'
And CCU.COLUMN_NAME = C.COLUMN_NAME
) As Z
Where C.TABLE_NAME = 'Table'
【讨论】：
好吧。它没有给我所需的结果:(【参考方案8】：没有人提到我有点惊讶
sp_help 'mytable'
【讨论】：
【参考方案9】：将另一个答案放入环中，这将为您提供这些列以及更多内容：
SELECT col.TABLE_CATALOG AS [Database]
, col.TABLE_SCHEMA AS Owner
, col.TABLE_NAME AS TableName
, col.COLUMN_NAME AS ColumnName
, col.ORDINAL_POSITION AS OrdinalPosition
, col.COLUMN_DEFAULT AS DefaultSetting
, col.DATA_TYPE AS DataType
, col.CHARACTER_MAXIMUM_LENGTH AS MaxLength
, col.DATETIME_PRECISION AS DatePrecision
, CAST(CASE col.IS_NULLABLE
WHEN 'NO' THEN 0
ELSE 1
END AS bit)AS IsNullable
, COLUMNPROPERTY(OBJECT_ID('[' + col.TABLE_SCHEMA + '].[' + col.TABLE_NAME + ']'), col.COLUMN_NAME, 'IsIdentity')AS IsIdentity
, COLUMNPROPERTY(OBJECT_ID('[' + col.TABLE_SCHEMA + '].[' + col.TABLE_NAME + ']'), col.COLUMN_NAME, 'IsComputed')AS IsComputed
, CAST(ISNULL(pk.is_primary_key, 0)AS bit)AS IsPrimaryKey
FROM INFORMATION_SCHEMA.COLUMNS AS col
LEFT JOIN(SELECT SCHEMA_NAME(o.schema_id)AS TABLE_SCHEMA
, o.name AS TABLE_NAME
, c.name AS COLUMN_NAME
, i.is_primary_key
FROM sys.indexes AS i JOIN sys.index_columns AS ic ON i.object_id = ic.object_id
AND i.index_id = ic.index_id
JOIN sys.objects AS o ON i.object_id = o.object_id
LEFT JOIN sys.columns AS c ON ic.object_id = c.object_id
AND c.column_id = ic.column_id
WHERE i.is_primary_key = 1)AS pk ON col.TABLE_NAME = pk.TABLE_NAME
AND col.TABLE_SCHEMA = pk.TABLE_SCHEMA
AND col.COLUMN_NAME = pk.COLUMN_NAME
WHERE col.TABLE_NAME = 'YourTableName'
AND col.TABLE_SCHEMA = 'dbo'
ORDER BY col.TABLE_NAME, col.ORDINAL_POSITION;
【讨论】：
【参考方案10】：SELECT COLUMN_NAME, IS_NULLABLE, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH FROM information_schema.columns WHERE table_name = '<name_of_table_or_view>'
在上面的语句中运行SELECT *，看看information_schema.columns返回了什么。
这个问题之前已经回答过 - https://***.com/a/11268456/6169225
【讨论】：
如果该问题已被回答，将帖子标记为重复。 使用 'information_schema.columns' 我们可以查看所有表格列的信息，包括查看表格名称和架构。【参考方案11】：在查询编辑器中输入表名，选择名称并按Alt+F1，它将带来该表的所有信息。
【讨论】：
他要求查询，但你是对的，这样你就可以看到所有的信息。【参考方案12】：IF EXISTS (SELECT 1 FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_NAME = 'Table')
BEGIN
SELECT COLS.COLUMN_NAME, COLS.DATA_TYPE, COLS.CHARACTER_MAXIMUM_LENGTH,
(SELECT 'Yes' FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS TC JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU
ON COLS.TABLE_NAME = TC.TABLE_NAME
AND TC.CONSTRAINT_TYPE = 'PRIMARY KEY'
AND KCU.TABLE_NAME = TC.TABLE_NAME
AND KCU.CONSTRAINT_NAME = TC.CONSTRAINT_NAME
AND KCU.COLUMN_NAME = COLS.COLUMN_NAME) AS KeyX
FROM INFORMATION_SCHEMA.COLUMNS COLS WHERE TABLE_NAME = 'Table' ORDER BY KeyX DESC, COLUMN_NAME
END
【讨论】：
【参考方案13】：marc_s 的答案很好，但是如果主键列出现在其他索引中，则存在一个缺陷，因为这些列会出现多次。例如
演示：
create table dbo.DummyTable
(
id int not null identity(0,1) primary key,
Msg varchar(80) null
);
create index NC_DummyTable_id ON DummyTable(id);
这是我解决问题的存储过程：
create or alter procedure dbo.GetTableColumns
(
@schemaname nvarchar(128),
@tablename nvarchar(128)
)
AS
BEGIN
SET NOCOUNT ON;
with ctePKCols as
(
select
i.object_id,
ic.column_id
from
sys.indexes i
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
)
SELECT
c.name AS column_name,
t.name AS typename,
c.max_length AS MaxLength,
c.precision,
c.scale,
c.is_nullable,
is_primary_key = CASE WHEN ct.column_id IS NOT NULL THEN 1 ELSE 0 END
FROM
sys.columns c
JOIN sys.types t ON t.user_type_id = c.user_type_id
LEFT JOIN ctePKCols ct ON ct.column_id = c.column_id AND ct.object_id = c.object_id
WHERE
c.object_ID = OBJECT_ID(quotename(@schemaname) + '.' + quotename(@tablename))
END
GO
exec dbo.GetTableColumns 'dbo', 'DummyTable'
【讨论】：
【参考方案14】：查找数据类型和长度的组合结果，并且可以以“NULL”和“Not null”的形式为空。使用下面的查询。
SELECT c.name AS 'Column Name',
t.name + '(' + cast(c.max_length as varchar(50)) + ')' As 'DataType',
case
WHEN c.is_nullable = 0 then 'null' else 'not null'
END AS 'Constraint'
FROM sys.columns c
JOIN sys.types t
ON c.user_type_id = t.user_type_id
WHERE c.object_id = Object_id('TableName')
你会发现如下所示的结果。
谢谢。
【讨论】：
你的约束条件应该是相反的。【参考方案15】：查询： EXEC SP_DESCRIBE_FIRST_RESULT_SET N'SELECT ANNUAL_INCOME FROM [DB_NAME].[DBO].[EMPLOYEE]'
注意：在某些 IDE 中，SELECT N 正在工作，或者在某些 IDE 中没有 N 正在工作
【讨论】：
【参考方案16】：select
c.name as [column name],
t.name as [type name],
tbl.name as [table name]
from sys.columns c
inner join sys.types t
on c.system_type_id = t.system_type_id
inner join sys.tables tbl
on c.object_id = tbl.object_id
where
c.object_id = OBJECT_ID('YourTableName1')
and
t.name like '%YourSearchDataType%'
union
(select
c.name as [column name],
t.name as [type name],
tbl.name as [table name]
from sys.columns c
inner join sys.types t
on c.system_type_id = t.system_type_id
inner join sys.tables tbl
on c.object_id = tbl.object_id
where
c.object_id = OBJECT_ID('YourTableName2')
and
t.name like '%YourSearchDataType%')
union
(select
c.name as [column name],
t.name as [type name],
tbl.name as [table name]
from sys.columns c
inner join sys.types t
on c.system_type_id = t.system_type_id
inner join sys.tables tbl
on c.object_id = tbl.object_id
where
c.object_id = OBJECT_ID('YourTableName3')
and
t.name like '%YourSearchDataType%')
order by tbl.name
根据您在一个数据库中的三个不同表的搜索数据类型来搜索哪一列在哪个表中。此查询可扩展到“n”个表。
【讨论】：
【参考方案17】：SELECT
T.NAME AS [TABLE NAME]
,C.NAME AS [COLUMN NAME]
,P.NAME AS [DATA TYPE]
,P.MAX_LENGTH AS [Max_SIZE]
,C.[max_length] AS [ActualSizeUsed]
,CAST(P.PRECISION AS VARCHAR) +'/'+ CAST(P.SCALE AS VARCHAR) AS [PRECISION/SCALE]
FROM SYS.OBJECTS AS T
JOIN SYS.COLUMNS AS C
ON T.OBJECT_ID = C.OBJECT_ID
JOIN SYS.TYPES AS P
ON C.SYSTEM_TYPE_ID = P.SYSTEM_TYPE_ID
AND C.[user_type_id] = P.[user_type_id]
WHERE T.TYPE_DESC='USER_TABLE'
AND T.name = 'InventoryStatus'
ORDER BY 2
【讨论】：
请使用缩进代替内联标记，并为您的答案添加一些解释。 为什么按 2 排序？【参考方案18】：这里没有主键，但这可以帮助其他只想拥有包含字段名称和基本字段属性的表名的用户
USE [**YourDB**]
GO
SELECT tbl.name, fld.[Column Name],fld.[Constraint],fld.DataType
FROM sys.all_objects as tbl left join
(SELECT c.OBJECT_ID, c.name AS 'Column Name',
t.name + '(' + cast(c.max_length as varchar(50)) + ')' As 'DataType',
case
WHEN c.is_nullable = 0 then 'null' else 'not null'
END AS 'Constraint'
FROM sys.columns c
JOIN sys.types t
ON c.user_type_id = t.user_type_id
) as fld on tbl.OBJECT_ID = fld.OBJECT_ID
WHERE ( tbl.[type]='U' and tbl.[is_ms_shipped] = 0)
ORDER BY tbl.[name],fld.[Column Name]
GO
【讨论】：
【参考方案19】：我刚刚做好了 marc_s 的“演示准备”：
SELECT
c.name 'Column Name',
t.name 'Data type',
IIF(t.name = 'nvarchar', c.max_length / 2, c.max_length) 'Max Length',
c.precision 'Precision',
c.scale 'Scale',
IIF(c.is_nullable = 0, 'No', 'Yes') 'Nullable',
IIF(ISNULL(i.is_primary_key, 0) = 0, 'No', 'Yes') 'Primary Key'
FROM
sys.columns c
INNER JOIN
sys.types t ON c.user_type_id = t.user_type_id
LEFT OUTER JOIN
sys.index_columns ic ON ic.object_id = c.object_id AND ic.column_id = c.column_id
LEFT OUTER JOIN
sys.indexes i ON ic.object_id = i.object_id AND ic.index_id = i.index_id
WHERE
c.object_id = OBJECT_ID('YourTableName')
【讨论】：
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