Question

我有一个查询，它会返回一个列的名称

SELECT name 
FROM sys.columns 
WHERE object_id = OBJECT_ID('tblu_utenti_00') AND name LIKE '%ling%'

对于该列，我想知道它是否有FK以及FK指向哪个表。

Answer 1

您可以查询目录视图以获取该信息 - 这是“通用”查询，它显示所有已定义的外键关系以及它们引用的表/列：

SELECT
    ForeignKeyName = fk.name,
    ParentTableName = parent.name,
    ParentColumnName = parcol.name,
    ReferencedTableName = referenced.Name,
    ReferencedColumnName = refcol.name
FROM 
    sys.foreign_keys fk
INNER JOIN 
    sys.foreign_key_columns fkc ON fk.object_id = fkc.constraint_object_id
INNER JOIN 
    sys.tables parent ON parent.object_id = fk.parent_object_id
INNER JOIN 
    sys.tables referenced ON referenced.object_id = fk.referenced_object_id
INNER JOIN 
    sys.columns parcol ON fkc.parent_object_id = parcol.object_id AND fkc.parent_column_id = parcol.column_id
INNER JOIN 
    sys.columns refcol ON fkc.referenced_object_id = refcol.object_id AND fkc.referenced_column_id = refcol.column_id

现在可以将此连接到sys.columns查询，并检查该列是否用作任何外键约束中的“父列”或“引用列”。

.....
WHERE
    (parent.Name = 'tblu_utenti_00' AND parcol.Name LIKE '%ling%')
    OR
    (referenced.Name = 'tblu_utenti_00' AND refcol.Name LIKE '%ling%')

T-SQL：如何找出FK指向的位置？

1 个答案: