SQL Server列約束和依賴關係

我需要在GUI應用程序中執行DDL語句。對於刪除列語句，我需要先刪除所有約束和依賴關係。到目前爲止，我知道：SQL Server列約束和依賴關係

主鍵約束
外鍵約束
唯一約束
檢查約束
默認約束
指數依賴

是否有任何我在c之前必須刪除的其他約束或依賴關係執行DROP TABLE COLUMN聲明？

2013-06-03 My-Name-Is

這是在回答[文件]（http://msdn.microsoft.com/en-us/library/ms190273.aspx），其正好列出了你上面的要點。 – Pondlife

感謝您的回覆！我很抱歉，但在本文檔中，我無法弄清楚是否必須刪除任何進一步的限制。這個問題的原因是，因爲我沒有使用SQL Server的經驗，今天我第一次聽說了'Default Constraints'。所以我絕對想避免由於未知的約束類型而導致「DROP COLUMN」聲明失敗。 –

您是否閱讀過關於約束的[documentation]（http://msdn.microsoft.com/zh-cn/library/ms189862（v = sql.105）.aspx）？我並不完全確定，如果擔心自己對SQL Server不夠了解（在這種情況下，文檔是很好的參考資料），或者擔心文檔不完整和準確？ – Pondlife

這些現在最後的工作SQL語句：

protected final String ASSEMBLE_DROP_DEFAULT_CONSTRAINT_STATEMENT_FOR_TABLE_COLUMN = "SELECT " 
     + "'ALTER TABLE '+t.name+' DROP CONSTRAINT '+df.name 'DropDefaultConstraintStatement' " 
     + ", c.name 'ColName' " 
     + "FROM sys.default_constraints df " 
     + "INNER JOIN sys.tables t ON df.parent_object_id = t.object_id " 
     + "INNER JOIN sys.columns c ON df.parent_object_id = c.object_id AND df.parent_column_id = c.column_id " 
     + "WHERE t.name = ? AND c.name = ?"; 

protected final String ASSEMBLE_DROP_CONSTRAINT_STATEMENTS_FOR_TABLE_COLUMN = "WITH CTE AS " 
     + "(" 
     + "SELECT OBJECT_NAME(parent_object_id) AS TABLE_NAME, name AS CONSTRAINT_NAME, Type " 
     + "FROM sys.key_constraints " 
     + "WHERE parent_object_id = object_id(?) " 
     + "UNION " 
     + "SELECT OBJECT_NAME(parent_object_id) AS TABLE_NAME, name AS CONSTRAINT_NAME, Type " 
     + "FROM sys.foreign_keys " 
     + "WHERE parent_object_id = object_id(?) " 
     + "UNION " 
     + "SELECT OBJECT_NAME(parent_object_id) AS TABLE_NAME, name AS CONSTRAINT_NAME, Type " 
     + "FROM sys.check_constraints " 
     + "WHERE parent_object_id = object_id(?) " 
     + ") " 
     + "SELECT DISTINCT " 
     + "'ALTER TABLE '+cte.TABLE_NAME+' DROP CONSTRAINT '+cte.CONSTRAINT_NAME AS 'DropConstraintStatement', " 
     + "CASE WHEN Type = 'PK' THEN 1 ELSE 0 END 'Is PK', ccu.COLUMN_NAME " 
     + "FROM CTE cte " 
     + "INNER JOIN INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE ccu " 
     + "ON cte.CONSTRAINT_NAME = ccu.CONSTRAINT_NAME " 
     + "WHERE ccu.COLUMN_NAME = ? " 
     + "ORDER BY CASE WHEN Type = 'PK' THEN 1 ELSE 0 END DESC;"; 

protected final String ASSEMBLE_DROP_ALL_FK_CONSTRAINTS_FOR_REFERENCED_TABLE_COLUMN = "SELECT " 
     + "'ALTER TABLE ' + OBJECT_NAME(fk.parent_object_id) + ' DROP CONSTRAINT ' + fk.name 'DropFKStatement', " 
     + "fk.name, " 
     + "OBJECT_NAME(fk.parent_object_id) 'Parent table', " 
     + "c1.name 'Parent column', " 
     + "OBJECT_NAME(fk.referenced_object_id) 'Referenced table', " 
     + "c2.name 'Referenced column' " 
     + "FROM sys.foreign_keys fk " 
     + "INNER JOIN sys.foreign_key_columns fkc " 
     + "ON fkc.constraint_object_id = fk.object_id " 
     + "INNER JOIN sys.columns c1 " 
     + "ON fkc.parent_column_id = c1.column_id AND fkc.parent_object_id = c1.object_id " 
     + "INNER JOIN sys.columns c2 ON " 
     + "fkc.referenced_column_id = c2.column_id AND fkc.referenced_object_id = c2.object_id " 
     + "WHERE OBJECT_NAME(fk.referenced_object_id) = ? AND c2.name = ?"; 

protected final String ASSEMBLE_DROP_INDEX_CONSTRAINT_STATEMENTS_FOR_TABLE_COLUMN = "SELECT " 
     + "'DROP INDEX '+ind.name+' ON ' + t.name " 
     + "FROM sys.indexes ind " 
     + "INNER JOIN sys.index_columns ic " 
     + "ON ind.object_id = ic.object_id and ind.index_id = ic.index_id " 
     + "INNER JOIN sys.columns col " 
     + "ON ic.object_id = col.object_id and ic.column_id = col.column_id " 
     + "INNER JOIN sys.tables t " 
     + "ON ind.object_id = t.object_id " 
     + "WHERE " 
     + "ind.is_primary_key = 0 " 
     + "AND ind.is_unique = 0 " 
     + "AND ind.is_unique_constraint = 0 " 
     + "AND t.name = ? AND col.name = ?";

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2013-06-24 14:26:09

SQL Server列約束和依賴關係

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