How to close connection with returned value in PyMySQL lib?











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0
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I have the following code:



import pymysql.cursors
class MylocalSQL:

def __init__(self):
pass

def get_max_report_date(self):
connection = pymysql.connect(host=...,
charset='utf8mb4',
cursorclass=pymysql.cursors.DictCursor)
try:
with connection.cursor() as cursor:
# Read a single record
sql = "SELECT value from tab limit 1 "
cursor.execute(sql)
result = cursor.fetchone()
print(result)
finally:
connection.close()


if __name__ == '__main__':
mysql = MylocalSQL()
mysql.get_max_report_date()


I want to change the print(result) into return so i can do:



value = mysql.get_max_report_date()


However if I change the print(result) into return result then the finally block won't be executed.



Is there a better way to manage the connection & handling errors while being able to return the value from the query?










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    up vote
    0
    down vote

    favorite












    I have the following code:



    import pymysql.cursors
    class MylocalSQL:

    def __init__(self):
    pass

    def get_max_report_date(self):
    connection = pymysql.connect(host=...,
    charset='utf8mb4',
    cursorclass=pymysql.cursors.DictCursor)
    try:
    with connection.cursor() as cursor:
    # Read a single record
    sql = "SELECT value from tab limit 1 "
    cursor.execute(sql)
    result = cursor.fetchone()
    print(result)
    finally:
    connection.close()


    if __name__ == '__main__':
    mysql = MylocalSQL()
    mysql.get_max_report_date()


    I want to change the print(result) into return so i can do:



    value = mysql.get_max_report_date()


    However if I change the print(result) into return result then the finally block won't be executed.



    Is there a better way to manage the connection & handling errors while being able to return the value from the query?










    share|improve this question
























      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      I have the following code:



      import pymysql.cursors
      class MylocalSQL:

      def __init__(self):
      pass

      def get_max_report_date(self):
      connection = pymysql.connect(host=...,
      charset='utf8mb4',
      cursorclass=pymysql.cursors.DictCursor)
      try:
      with connection.cursor() as cursor:
      # Read a single record
      sql = "SELECT value from tab limit 1 "
      cursor.execute(sql)
      result = cursor.fetchone()
      print(result)
      finally:
      connection.close()


      if __name__ == '__main__':
      mysql = MylocalSQL()
      mysql.get_max_report_date()


      I want to change the print(result) into return so i can do:



      value = mysql.get_max_report_date()


      However if I change the print(result) into return result then the finally block won't be executed.



      Is there a better way to manage the connection & handling errors while being able to return the value from the query?










      share|improve this question













      I have the following code:



      import pymysql.cursors
      class MylocalSQL:

      def __init__(self):
      pass

      def get_max_report_date(self):
      connection = pymysql.connect(host=...,
      charset='utf8mb4',
      cursorclass=pymysql.cursors.DictCursor)
      try:
      with connection.cursor() as cursor:
      # Read a single record
      sql = "SELECT value from tab limit 1 "
      cursor.execute(sql)
      result = cursor.fetchone()
      print(result)
      finally:
      connection.close()


      if __name__ == '__main__':
      mysql = MylocalSQL()
      mysql.get_max_report_date()


      I want to change the print(result) into return so i can do:



      value = mysql.get_max_report_date()


      However if I change the print(result) into return result then the finally block won't be executed.



      Is there a better way to manage the connection & handling errors while being able to return the value from the query?







      python pymysql






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 11 at 10:04









      Luis

      267




      267
























          2 Answers
          2






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          up vote
          0
          down vote



          accepted










          You are mistaken about the behavior of finally. The finally block is executed, even if you have the return statement.



          class MylocalSQL:

          def __init__(self):
          pass

          def get_max_report_date(self):
          try:
          return "some value"
          finally:
          print('i was executed')


          MylocalSQL().get_max_report_date()


          prints "I was executed"



          https://ideone.com/KhvVKy






          share|improve this answer




























            up vote
            0
            down vote













            Create a variable before. Assign the result to your variable. Close the connection. Return the variable.






            share|improve this answer





















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              2 Answers
              2






              active

              oldest

              votes








              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes








              up vote
              0
              down vote



              accepted










              You are mistaken about the behavior of finally. The finally block is executed, even if you have the return statement.



              class MylocalSQL:

              def __init__(self):
              pass

              def get_max_report_date(self):
              try:
              return "some value"
              finally:
              print('i was executed')


              MylocalSQL().get_max_report_date()


              prints "I was executed"



              https://ideone.com/KhvVKy






              share|improve this answer

























                up vote
                0
                down vote



                accepted










                You are mistaken about the behavior of finally. The finally block is executed, even if you have the return statement.



                class MylocalSQL:

                def __init__(self):
                pass

                def get_max_report_date(self):
                try:
                return "some value"
                finally:
                print('i was executed')


                MylocalSQL().get_max_report_date()


                prints "I was executed"



                https://ideone.com/KhvVKy






                share|improve this answer























                  up vote
                  0
                  down vote



                  accepted







                  up vote
                  0
                  down vote



                  accepted






                  You are mistaken about the behavior of finally. The finally block is executed, even if you have the return statement.



                  class MylocalSQL:

                  def __init__(self):
                  pass

                  def get_max_report_date(self):
                  try:
                  return "some value"
                  finally:
                  print('i was executed')


                  MylocalSQL().get_max_report_date()


                  prints "I was executed"



                  https://ideone.com/KhvVKy






                  share|improve this answer












                  You are mistaken about the behavior of finally. The finally block is executed, even if you have the return statement.



                  class MylocalSQL:

                  def __init__(self):
                  pass

                  def get_max_report_date(self):
                  try:
                  return "some value"
                  finally:
                  print('i was executed')


                  MylocalSQL().get_max_report_date()


                  prints "I was executed"



                  https://ideone.com/KhvVKy







                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered Nov 11 at 10:09









                  Uku Loskit

                  29.8k86779




                  29.8k86779
























                      up vote
                      0
                      down vote













                      Create a variable before. Assign the result to your variable. Close the connection. Return the variable.






                      share|improve this answer

























                        up vote
                        0
                        down vote













                        Create a variable before. Assign the result to your variable. Close the connection. Return the variable.






                        share|improve this answer























                          up vote
                          0
                          down vote










                          up vote
                          0
                          down vote









                          Create a variable before. Assign the result to your variable. Close the connection. Return the variable.






                          share|improve this answer












                          Create a variable before. Assign the result to your variable. Close the connection. Return the variable.







                          share|improve this answer












                          share|improve this answer



                          share|improve this answer










                          answered Nov 11 at 10:05









                          NielsNet

                          38818




                          38818






























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