Firebird點網絡提供者沒有完全執行查詢？

Question

我在C＃中使用Firebird的dot net提供程序運行一些SQL命令。具體來說，我正在更改數據庫模式，並進行數據更新等。

作爲我的處理的一部分，我創建一個新表，運行查詢以從舊錶中複製數據，然後刪除舊錶。

當我做這個火鳥生成和錯誤：

unsuccessful metadata update object is in use

我已經做了一些看，它似乎像查詢複製的數據沒有被「清除」我們什麼呢。我的意思是當我檢查Firebird中的監控表時，我的c＃執行已暫停，我在MON$STATEMENTS表中看到查詢爲非活動狀態。這是我運行一個提交語句後。

我的問題：

有沒有辦法暫停，或等待，或強制查詢，全面完成之前，我嘗試運行下一個命令？

當我在ISQL中運行相同的查詢序列時，它可以很好地工作。有什麼不同的ISQL，我可以強制點網Firebird提供程序這樣做，它不會保持此查詢打開或什麼？

所以對於參考的代碼看起來是這樣的（顯然這是一個很簡單的）：

// create the table 
    string commandString = "CREATE TABLE ..."; 

    // run the command in a transaction and commit it 
    mtransaction = Connection.BeginTransaction(IsolationLevel.Serializable); 
    FbCommand command = new FbCommand(commandString, Connection, mtransaction); 
    command.ExecuteNonQuery(); 
    transaction.Commit(); 
    transaction.Dispose(); 
    transaction = null; 

    // copy the data to the new table from the old 
    commandString = "INSERT INTO ..."; 

    mtransaction = Connection.BeginTransaction(IsolationLevel.Serializable); 
    FbCommand command = new FbCommand(commandString, Connection, mtransaction); 
    command.ExecuteNonQuery(); 
    transaction.Commit(); 
    transaction.Dispose(); 
    transaction = null; 

    // drop the old table 
    commandString = "DROP TABLE ..."; 

    mtransaction = Connection.BeginTransaction(IsolationLevel.Serializable); 
    FbCommand command = new FbCommand(commandString, Connection, mtransaction); 
    command.ExecuteNonQuery(); 

    // this command fails with the exception 
    // if I pause execution in c# before running this command, and 
    // use isql to look at the db I see the new table, and the data fully populated 
    // and I also see the inactive insert command in MON$STATEMENTS 
    transaction.Commit(); 
    transaction.Dispose(); 
    transaction = null; 

Answer 1

好了，可怕的問題的解決方案：

我居然能得到這個由工作關閉和處理連接，然後重新連接。這導致「卡住」查詢以某種方式被移除，然後我可以執行表格放置命令。所以順序看起來像這樣：

// create the table 
string commandString = "CREATE TABLE ..."; 

// run the command in a transaction and commit it 
mtransaction = Connection.BeginTransaction(IsolationLevel.Serializable); 
FbCommand command = new FbCommand(commandString, Connection, mtransaction); 
command.ExecuteNonQuery(); 
transaction.Commit(); 
transaction.Dispose(); 
transaction = null; 

// copy the data to the new table from the old 
commandString = "INSERT INTO ..."; 

mtransaction = Connection.BeginTransaction(IsolationLevel.Serializable); 
FbCommand command = new FbCommand(commandString, Connection, mtransaction); 
command.ExecuteNonQuery(); 
transaction.Commit(); 
transaction.Dispose(); 
transaction = null; 


// ------------------ 
// Drop the connection entirely and start a new one 
// so the table can be dropped 

Connection.Close(); 
Connection.Dispose(); 

// build connection string 
FbConnectionStringBuilder csb = new FbConnectionStringBuilder(); 
csb.DataSource ... etc... 

// connect 
Connection = new FbConnection(connectionString); 
Connection.Open(); 

// Now have new connection that does not have weird 
// lingering query, and table can now be dropped 
// ----------------- 



// drop the old table 
commandString = "DROP TABLE ..."; 

mtransaction = Connection.BeginTransaction(IsolationLevel.Serializable); 
FbCommand command = new FbCommand(commandString, Connection, mtransaction); 
command.ExecuteNonQuery(); 

// this no longer fails because the connection was complete closed 
// and re-opened 
transaction.Commit(); 
transaction.Dispose(); 
transaction = null; 

注意：我對此解決方案非常不滿意。它有效，但我不知道爲什麼。我不得不這樣做放棄一張桌子，這對我來說過分而不切實際。我會非常感謝任何人在這件事上可能提供的見解！

Answer 2

我相信我遇到了類似的事情。我的猜測是，根本原因似乎是一個特點：MVCC。當我混淆模式，或只刪除表然後重新創建時，Visual Studio通常會將其保持爲打開狀態。我只是重新啓動服務，一切都很好。

Answer 3

我遇到了同樣的問題，並驗證了Beau's（原始）修補程序。然而，我發現了一個簡單的解決方案：在事務提交後處理命令！然後重新連接不再需要。

mtransaction = Connection.BeginTransaction(IsolationLevel.Serializable); 
FbCommand command = new FbCommand(commandString, Connection, mtransaction); 
command.ExecuteNonQuery(); 
transaction.Commit(); 
command.Dispose(); // Thus! 
transaction.Dispose(); 

問候， 航標