sql server 约束 查找

--1.主键约束
SELECT
  tab.name AS [表名],
  idx.name AS [主键名称],
  col.name AS [主键列名]
FROM
  sys.indexes idx
    JOIN sys.index_columns idxCol
      ON (idx.object_id = idxCol.object_id
          AND idx.index_id = idxCol.index_id
          AND idx.is_primary_key = 1)
    JOIN sys.tables tab
      ON (idx.object_id = tab.object_id)
    JOIN sys.columns col
      ON (idx.object_id = col.object_id
          AND idxCol.column_id = col.column_id);

--2.唯一约束
SELECT
  tab.name AS [表名],
  idx.name AS [约束名称],
  col.name AS [约束列名]
FROM
  sys.indexes idx
    JOIN sys.index_columns idxCol
      ON (idx.object_id = idxCol.object_id
          AND idx.index_id = idxCol.index_id
          AND idx.is_unique_constraint = 1)
    JOIN sys.tables tab
      ON (idx.object_id = tab.object_id)
    JOIN sys.columns col
      ON (idx.object_id = col.object_id
          AND idxCol.column_id = col.column_id);

 --3.外键约束
 select
  oSub.name  AS  [子表名称],
  fk.name AS  [外键名称],
  SubCol.name AS [子表列名],
  oMain.name  AS  [主表名称],
  MainCol.name AS [主表列名]
from
  sys.foreign_keys fk
    JOIN sys.all_objects oSub
        ON (fk.parent_object_id = oSub.object_id)
    JOIN sys.all_objects oMain
        ON (fk.referenced_object_id = oMain.object_id)
    JOIN sys.foreign_key_columns fkCols
        ON (fk.object_id = fkCols.constraint_object_id)
    JOIN sys.columns SubCol
        ON (oSub.object_id = SubCol.object_id
            AND fkCols.parent_column_id = SubCol.column_id)
    JOIN sys.columns MainCol
        ON (oMain.object_id = MainCol.object_id
            AND fkCols.referenced_column_id = MainCol.column_id)

 --4.Check约束
 SELECT
  tab.name AS [表名],
  chk.name AS [Check约束名],
  col.name AS [列名],
  chk.definition
FROM
  sys.check_constraints chk
    JOIN sys.tables tab
      ON (chk.parent_object_id = tab.object_id)
    JOIN sys.columns col
      ON (chk.parent_object_id = col.object_id
          AND chk.parent_column_id = col.column_id)