我需要在SQL server上编写一个查询,以获得特定表中的列列表,其相关数据类型(长度)以及它们是否不为空。我已经做到了这么多。
但现在我还需要得到,在同一个表中,对一个列- TRUE,如果该列是一个主键。
我该怎么做呢?
我的期望输出是:
Column name | Data type | Length | isnull | Pk
我需要在SQL server上编写一个查询,以获得特定表中的列列表,其相关数据类型(长度)以及它们是否不为空。我已经做到了这么多。
但现在我还需要得到,在同一个表中,对一个列- TRUE,如果该列是一个主键。
我该怎么做呢?
我的期望输出是:
Column name | Data type | Length | isnull | Pk
当前回答
为了避免某些列的重复行,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替换为实际的表名-适用于SQL Server 2005及更高版本。
如果您正在使用模式,请将YourTableName替换为YourSchemaName。YourTableName,其中YourSchemaName是实际的模式名,YourTableName是实际的表名。
其他回答
我刚刚做了marc_s“presentation ready”:
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')
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 *,以查看information_schema. schema是什么。列的回报。
这个问题之前已经回答过了- https://stackoverflow.com/a/11268456/6169225
我有点惊讶居然没人提
sp_help 'mytable'
将另一个答案放入环中,这将给你这些列和更多:
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;
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