在使用pyodbc 從 python 連到 MSSQL 時，當有一個 thread 固定在 polling database 裡的值，但每次連database 不是重新建立 connection 而是沿用 global 的 connection，在重啟 sql server 時可以遇到這個 Error.
('08S01', '[08S01] [Microsoft][ODBC Driver 13 for SQL Server]Communication link failure (0) (SQLExecDirectW)')
如果是去取得 table 物件，會遇到這一個 Error:
('08S01', '[08S01] [Microsoft][ODBC Driver 13 for SQL Server]Communication link failure (0) (SQLTables)'
python 2.7 – How to re-establish connection after communication link failure with pyodbc?
Per my experience, I think may be you can try to use the code below to implement the retry logic.
import time
retry_flag = True
retry_count = 0
while retry_flag and retry_count < 5:
try:
cursor.execute(query, [args['type'], args['id']])
retry_flag = False
except:
print "Retry after 1 sec"
retry_count = retry_count + 1
time.sleep(1)
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