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

在查询编辑器中选择表名并按Alt+F1,它将带来表的所有信息。

其他回答

为了确保获得正确的长度,需要将unicode类型视为一种特殊情况。参见下面的代码。

更多信息请参见: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')

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。

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')

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;

在SQL 2012中,你可以使用:

EXEC sp_describe_first_result_set N'SELECT * FROM [TableName]'

这将为您提供列名及其属性。