如何從Oracle數據庫獲取NCLOB XML數據

Question

我們使用基於Java的應用程序來部署XML文件，這些文件被寫入Oracle數據庫。 db中的XML blob存儲爲NCLOB數據類型。我將如何從數據庫獲取NCLOB XML數據並將其轉換回XML格式？我需要使用Java（我是一個完整的Java noob，BTW），還是我可以在這裏使用PowerShell（我的首選項）？取決於方法，我將如何做到這一點？

我想這樣做的原因主要是前/後部署驗證（比較部署之前和之後的XML內容）。

由於提前， 基思

Answer 1

這是我在過去所做的那樣使用ODAC在甲骨文CLOB讀/寫XML。這應該適用於NCLOB，只需很少的修改。

# Load ODAC. This might fail if it is not installed or is the wrong bitness. 
$assembly = [System.Reflection.Assembly]::LoadWithPartialName("Oracle.DataAccess") 

# Connect to Oracle. 
$connStr = 'Data Source=hostname:1521/sidname; User Id=sys; Password=password; DBA Privilege=SYSDBA;' 
$conn = New-Object Oracle.DataAccess.Client.OracleConnection -ArgumentList $connStr 
$conn.Open() 

# Query the table. 
$q = "select MY_CLOB_FIELD from My_Table" 
$command = new-object Oracle.DataAccess.Client.OracleCommand($q, $conn) 

# Process records. 
$reader = $command.ExecuteReader() 
while ($reader.Read()) { 
    # Read the CLOB field and cast to an XML document. 
    $xmlDoc = [xml] $reader.getstring(0) # XML 

    #... XML Processing Here .... 

    # Commit the updated XML. 
    $sql = "UPDATE My_Table SET MY_CLOB_FIELD = :1" 
    $updateCmd = New-Object Oracle.DataAccess.Client.OracleCommand ($sql, $conn) 

    $param = New-Object Oracle.DataAccess.Client.OracleParameter (
     "xml", #Name 
     [Oracle.DataAccess.Client.OracleDbType]::Clob, #Type 
     $xmlDoc.OuterXml, #Data 
     'Input' #Direction 
    ) 

    $newParam = $updateCmd.Parameters.Add($param) 
    $result = $updateCmd.ExecuteNonQuery() 
} 

Answer 2

這是我最後使用的代碼：

$Assembly = [System.Reflection.Assembly]::LoadWithPartialName("System.Data.OracleClient") 

$conn = New-Object System.Data.OracleClient.OracleConnection(` 
「Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=hostname)(PORT=port)) ` 
(CONNECT_DATA=(SERVICE_NAME=SID)));User Id=username;Password=password;」); 

$conn.Open() 

# Query the table. 
$q = "SELECT column FROM table WHERE column='something'" 
$command = New-Object System.Data.OracleClient.OracleCommand ($q, $conn) 

$xmlfile = "c:\temp\xml\temp.xml" 
# Process records. 
$reader = $command.ExecuteReader() 
while ($reader.Read()) 
{ 
    # Read the NCLOB field and cast to an XML document. 
    $xmlDoc = [xml] $reader.getstring(0) # XML 
    $xmlDoc.Save($xmlfile) 
} 
$conn.Close() 

@Andy，用於操縱我的方向是正確的感謝！ :-)