错误：（'IM005'，“ [IM005] [unixODBC] [驱动程序管理器] SQL_HANDLE_DBC上驱动程序的SQLAllocHandle失败（0）（SQLDriverConnect）”）

Question

我正在尝试执行并行化的pyodbc脚本中运行此代码

templst = [lineitem, orders, partsupp, region, cur_cur, T1, T2]
connstr = [DRIVER={libdbodbc17.so};host=lint16muthab.phl.sap.corp:8766;UID=dba;PWD=sql;CharSet=utf8, DRIVER={libdbodbc17.so};host=localhost:8767;UID=dba;PWD=sql;CharSet=utf8,
           DRIVER={libdbodbc17.so};host=localhost:8768;UID=dba;PWD=sql;CharSet=utf8,
           DRIVER={libdbodbc17.so};host=localhost:8769;UID=dba;PWD=sql;CharSet=utf8, DRIVER={libdbodbc17.so};host=localhost:8770;UID=dba;PWD=sql;CharSet=utf8]

def extract_single(q, cursorconn):
    while True:
        try:
            tableName = q.get_nowait()
            time.sleep(3)
            qry2 = "Select * FROM %s"% (tableName)
            print " extraction done of table:%s done by cursor:%s"%(tableName,cursorconn)
        except Queue.Empty:
            return

def main():
    q = multiprocessing.Queue()
    for item in templst:
        q.put(item) # add items to queue
    process = []
    for i in xrange(5):
        p = multiprocessing.Process(target=extract_single, args=(q, connstr[i]))
        process.append(p)
        p.start()
    for p in process:
        p.join()

if __name__ == '__main__':
    main()

输出类似于：

  extraction done of table:lineitem done by cursor:DRIVER={libdbodbc17.so};host=lint16muthab.phl.sap.corp:8766;UID=dba;PWD=sql;CharSet=utf8

表的提取完成：游标完成的命令：DRIVER = {libdbodbc17.so}; host = localhost：8767; UID = dba; PWD = sql; CharSet = utf8

      extraction done of table:partsupp done by cursor:DRIVER={libdbodbc17.so};host=localhost:8768;UID=dba;PWD=sql;CharSet=utf8

      extraction done of table:region done by cursor:DRIVER={libdbodbc17.so};host=localhost:8769;UID=dba;PWD=sql;CharSet=utf8

      extraction done of table:cur_cur done by cursor:DRIVER={libdbodbc17.so};host=localhost:8770;UID=dba;PWD=sql;CharSet=utf8

     extraction done of table:T2 done by cursor:DRIVER={libdbodbc17.so};host=localhost:8767;UID=dba;PWD=sql;CharSet=utf8

     extraction done of table:T1 done by cursor:DRIVER={libdbodbc17.so};host=lint16muthab.phl.sap.corp:8766;UID=dba;PWD=sql;CharSet=utf8

但是当我将提取函数修改为

def extract_single(q, cursorconn):
    while True:
        try:
            tableName = q.get_nowait()
            time.sleep(3)
            conn = pyodbc.connect(cursorconn, timeout=0)
            cursor = connvar.cursor()
            qry2 = "Select * FROM %s"% (tableName)
            cursor.execute(qry2).fetchall()
            print " extraction done of table:%s done by cursor:%s"%(tableName,cursorconn)
        except Queue.Empty:
            return

我遇到错误，无法打开连接和游标，因此我可以执行此查询并将数据转储到文件中。

2Process Process-1:
Traceback (most recent call last):
  File "/sybopt/software/python/python/lib/python2.7/multiprocessing/process.py", line 258, in _bootstrap
    self.run()
  File "/sybopt/software/python/python/lib/python2.7/multiprocessing/process.py", line 114, in run
    self._target(*self._args, **self._kwargs)
  File "conn3.py", line 86, in extract_single
Process Process-2:
Traceback (most recent call last):
    connvar = pyodbc.connect(cursorconn, timeout=0)
  File "/sybopt/software/python/python/lib/python2.7/multiprocessing/process.py", line 258, in _bootstrap
Error: ('IM005', "[IM005] [unixODBC][Driver Manager]Driver's SQLAllocHandle on SQL_HANDLE_DBC failed (0) (SQLDriverConnect)")
    self.run()
  File "/sybopt/software/python/python/lib/python2.7/multiprocessing/process.py", line 114, in run
    self._target(*self._args, **self._kwargs)
  File "conn3.py", line 86, in extract_single
    connvar = pyodbc.connect(cursorconn, timeout=0)
Error: ('IM005', "[IM005] [unixODBC][Driver Manager]Driver's SQLAllocHandle on SQL_HANDLE_DBC failed (0) (SQLDriverConnect)")
Process Process-3:
Traceback (most recent call last):
  File "/sybopt/software/python/python/lib/python2.7/multiprocessing/process.py", line 258, in _bootstrap
    self.run()
  File "/sybopt/software/python/python/lib/python2.7/multiprocessing/process.py", line 114, in run
    self._target(*self._args, **self._kwargs)
  File "conn3.py", line 86, in extract_single
    connvar = pyodbc.connect(cursorconn, timeout=0)

对于所有连接。请让我知道如何解决此错误。

Answer 1

除了您遇到的问题之外，基于您先前的问题，我还假设cursorconn是一个已经打开的连接，可以在每个查询中重用。由于它现在似乎只是一个连接字符串，因此您应该在conn = pyodbc.connect(cursorconn, timeout=0)语句中进行调用while True: before，以便同一连接可以重用于多个查询，然后应在关闭连接之前您从函数返回。

我认为问题是语句cursor = connvar.cursor()，应为：cursor = conn.cursor()。因此，请尝试以下操作：

conn = pyodbc.connect(cursorconn, timeout=0)
while True:
    try:
        tableName = q.get_nowait()
        time.sleep(3) # why is this here?
        cursor = conn.cursor()
        qry2 = "Select * FROM %s"% (tableName)
        cursor.execute(qry2).fetchall()
        print " extraction done of table:%s done by cursor:%s"%(tableName,cursorconn)
        cursor.close() # should probably add this
    except Queue.Empty:
        return
    finally:
        conn.close()