SQL Server 2008：找出表中的主鍵/外鍵？

Question

有沒有人知道我怎麼能看到哪一個表中的主鍵&外鍵？

編輯：感謝所有的答覆。我正在尋找一個SQL查詢來做到這一點。現在我正在寫一個工具，它可以列出所有DB的表格並顯示列。我想顯示哪些鍵是主鍵。

這是我讀出表目錄：

const string sqlSelectTable = "SELECT TABLE_CATALOG, TABLE_SCHEMA, TABLE_NAME, TABLE_TYPE " + 
             "FROM INFORMATION_SCHEMA.TABLES " + 
             "WHERE TABLE_TYPE = 'BASE TABLE' " + 
             "ORDER BY TABLE_TYPE,TABLE_NAME"; 

而且這是我得到的相關信息約一列：

const string sqlSelectTable = 
      "SELECT  COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH " + 
      "FROM   INFORMATION_SCHEMA.COLUMNS " + 
      "WHERE  (TABLE_NAME = @TABLE_NAME) " + 
      "ORDER BY ORDINAL_POSITION"; 

我必須創建一個內加入這樣看哪列是主鍵？

乾杯

Answer 1

有關各表的主鍵，您可以使用此查詢：

SELECT 
    kc.name, 
    c.NAME 
FROM 
    sys.key_constraints kc 
INNER JOIN 
    sys.index_columns ic ON kc.parent_object_id = ic.object_id 
INNER JOIN 
    sys.columns c ON ic.object_id = c.object_id AND ic.column_id = c.column_id 
WHERE 
    kc.type = 'PK' 

和對於外鍵，我相信這個查詢應該會爲你提供必要的信息：

SELECT 
    OBJECT_NAME(parent_object_id) 'Parent table', 
    c.NAME 'Parent column name', 
    OBJECT_NAME(referenced_object_id) 'Referenced table', 
    cref.NAME 'Referenced column name' 
FROM 
    sys.foreign_key_columns fkc 
INNER JOIN 
    sys.columns c 
     ON fkc.parent_column_id = c.column_id 
      AND fkc.parent_object_id = c.object_id 
INNER JOIN 
    sys.columns cref 
     ON fkc.referenced_column_id = cref.column_id 
      AND fkc.referenced_object_id = cref.object_id 

馬克

Answer 2

在Management Studio中，展開表格，然後展開「列」項目。主鍵旁邊有一個鑰匙圖標。

要查看外鍵，請展開Constraints項目。

Answer 3

看到Querying the SQL Server System Catalog FAQ，How do I find the columns of a primary key for a specified table?和How do I find the columns of a foreign key for a specified table?

編輯：如果你想這樣做編程方式（這是不是從你的問題清楚），那是。

Answer 4

你可以開始：

SELECT 
    Table_Name as [TableName], 
    Column_Name as [ColumnName], 
    Constraint_Name as [Constraint], 
    Table_Schema as [Schema] 
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE 
ORDER BY 
    [TableName], 
    [ColumnName] 

（您可以通過表名過濾然後）

Answer 5

SELECT 
OBJECT_NAME(parent_object_id) 'Parent table', 
c.NAME 'Parent column name', 
OBJECT_NAME(referenced_object_id) 'Referenced table', 
cref.NAME 'Referenced column name' 
FROM 
sys.foreign_key_columns fkc 
INNER JOIN 
sys.columns c 
    ON fkc.parent_column_id = c.column_id 
     AND fkc.parent_object_id = c.object_id 
INNER JOIN 
sys.columns cref 
    ON fkc.referenced_column_id = cref.column_id 
     AND fkc.referenced_object_id = cref.object_id where OBJECT_NAME(parent_object_id) = 'tablename' 

如果你想獲得的所有表的外鍵關係，排除其他的where條款寫你的表名，而不是tablename