我试图通过 C# 在我的匿名 PL/SQL block 中获取 DBMS_OUTPUT.PUT_LINE()
方法的输出。我在这里查看了其他几个相关问题,但仍然遇到问题。执行匿名 block 的返回码是返回-1
,根据docs应该是正确的.
我将 DBMS_OUTPUT.ENABLE()
设置为 NULL
以便不设置特定的缓冲区大小,然后使用 DBMS_OUTPUT.GET_LINES()
方法以便从该缓冲区中获取行。
它在缓冲区中不返回任何内容(一个空的 OracleString[]
)并返回 0
行。我的匿名 PL/SQL block 很简单,但应该适用于任何地方。
DECLARE
lvsName VARCHAR2(6) := 'Oracle';
BEGIN
DBMS_OUTPUT.PUT_LINE('Do you see me?');
DBMS_OUTPUT.PUT_LINE('My name is: ' || lvsName);
END;
我错过了什么?
using (OracleDataAdapter oda = new OracleDataAdapter())
using (OracleCommand cmd = new OracleCommand(sql, _connection))
{
// Execute anonymous PL/SQL block
cmd.CommandType = CommandType.Text;
var res = cmd.ExecuteNonQuery();
// Set output Buffer
cmd.CommandText = "BEGIN DBMS_OUTPUT.ENABLE(NULL); END;";
cmd.CommandType = CommandType.Text;
cmd.ExecuteNonQuery();
// Get output
cmd.CommandText = "BEGIN DBMS_OUTPUT.GET_LINES(:outString, :numLines); END;";
cmd.CommandType = CommandType.Text;
cmd.Parameters.Clear();
cmd.Parameters.Add(new OracleParameter("outString", OracleDbType.Varchar2, int.MaxValue, ParameterDirection.Output));
cmd.Parameters["outString"].CollectionType = OracleCollectionType.PLSQLAssociativeArray;
cmd.Parameters["outString"].Size = sql.Length;
cmd.Parameters["outString"].ArrayBindSize = new int[sql.Length];
cmd.Parameters.Add(new OracleParameter("numLines", OracleDbType.Int32, ParameterDirection.InputOutput));
cmd.Parameters["numLines"].Value = 10; // Get 10 lines
cmd.ExecuteNonQuery();
int numLines = Convert.ToInt32(cmd.Parameters["numLines"].Value.ToString());
string outString = string.Empty;
// Try to get more lines until there are zero left
while (numLines > 0)
{
for (int i = 0; i < numLines; i++)
{
OracleString s = (OracleString)cmd.Parameters["outString"].Value;
outString += s.ToString();
}
cmd.ExecuteNonQuery();
numLines = Convert.ToInt32(cmd.Parameters["numLines"].Value.ToString());
}
return outString;
}
最佳答案
您的代码的主要问题是它没有为输出缓冲区的每个元素设置绑定(bind)大小。检索结果时也没有正确索引输出缓冲区。最后,执行顺序也很重要:在执行匿名代码块之前,您必须首先启用输出。所做的每一项更改都会在以下 MCVE 中进行评论.仅进行必要的更改以使其正常工作。
static void Main(string[] args)
{
string str = "User Id=xxx; password=xxx; Data Source=localhost:1521/xxx;";
string sql = @"DECLARE lvsName VARCHAR2(6) := 'Oracle'; BEGIN DBMS_OUTPUT.PUT_LINE('Do you see me?'); DBMS_OUTPUT.PUT_LINE('My name is: ' || lvsName); END;";
OracleConnection _connection = new OracleConnection(str);
try
{
_connection.Open();
//adapter not being used
//using (OracleDataAdapter oda = new OracleDataAdapter())
using (OracleCommand cmd = new OracleCommand(sql, _connection))
{
// First enable buffer output
// Set output Buffer
cmd.CommandText = "BEGIN DBMS_OUTPUT.ENABLE(NULL); END;";
cmd.CommandType = CommandType.Text;
cmd.ExecuteNonQuery();
// Then execute anonymous block
// Execute anonymous PL/SQL block
cmd.CommandText = sql;
cmd.CommandType = CommandType.Text;
var res = cmd.ExecuteNonQuery();
// Get output
cmd.CommandText = "BEGIN DBMS_OUTPUT.GET_LINES(:outString, :numLines); END;";
cmd.CommandType = CommandType.Text;
cmd.Parameters.Clear();
cmd.Parameters.Add(new OracleParameter("outString", OracleDbType.Varchar2, int.MaxValue, ParameterDirection.Output));
cmd.Parameters["outString"].CollectionType = OracleCollectionType.PLSQLAssociativeArray;
cmd.Parameters["outString"].Size = sql.Length;
cmd.Parameters["outString"].ArrayBindSize = new int[sql.Length];
// set bind size for each array element
for (int i = 0; i < sql.Length; i++)
{
cmd.Parameters["outString"].ArrayBindSize[i] = 32000;
}
cmd.Parameters.Add(new OracleParameter("numLines", OracleDbType.Int32, ParameterDirection.InputOutput));
cmd.Parameters["numLines"].Value = 10; // Get 10 lines
cmd.ExecuteNonQuery();
int numLines = Convert.ToInt32(cmd.Parameters["numLines"].Value.ToString());
string outString = string.Empty;
// Try to get more lines until there are zero left
while (numLines > 0)
{
for (int i = 0; i < numLines; i++)
{
// use proper indexing here
//OracleString s = (OracleString)cmd.Parameters["outString"].Value;
OracleString s = ((OracleString[])cmd.Parameters["outString"].Value)[i];
outString += s.ToString();
// add new line just for formatting
outString += "\r\n";
}
cmd.ExecuteNonQuery();
numLines = Convert.ToInt32(cmd.Parameters["numLines"].Value.ToString());
}
Console.WriteLine(outString);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
_connection.Close();
_connection.Dispose();
Console.WriteLine("Press RETURN to exit.");
Console.ReadLine();
}
输出结果为:
Do you see me?
My name is: Oracle
Press RETURN to exit.
关于c# - 从 C# 中的 DBMS_OUTPUT.GET_LINES 获取输出缓冲区,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/53402356/