Loading large mysql select statements into python











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I have two mysql databases called database A and database B. I want to use python to copy all the data from a table in database A to a table in database B. The datatable holds approximately 5M rows. I have written the following code:



connection = make_connection(source_db)

c = connection.cursor()

batch_size = 100000

while True:

    batch = c.fetchmany(batch_size)

    print('Extracted a batch.')

    if not batch:

        break

    insert_data(batch)



connection.close()


I ran this code and it takes minutes for fetchmany() to extract a single batch. I've tried to use fetchall() without the while True statement but this takes even longer.



Question: How do I successfully speed up this process/what is the best way to load large select statements into python?






mysql python-3.x







share|improve this question




























    up vote
    2
    down vote

    favorite












    I have two mysql databases called database A and database B. I want to use python to copy all the data from a table in database A to a table in database B. The datatable holds approximately 5M rows. I have written the following code:



    connection = make_connection(source_db)
    
c = connection.cursor()
    
batch_size = 100000
    
while True:
    
    batch = c.fetchmany(batch_size)
    
    print('Extracted a batch.')
    
    if not batch:
    
        break
    
    insert_data(batch)
    

    
connection.close()


    I ran this code and it takes minutes for fetchmany() to extract a single batch. I've tried to use fetchall() without the while True statement but this takes even longer.



    Question: How do I successfully speed up this process/what is the best way to load large select statements into python?






    mysql python-3.x







    share|improve this question


























      up vote
      2
      down vote

      favorite









      up vote
      2
      down vote

      favorite











      I have two mysql databases called database A and database B. I want to use python to copy all the data from a table in database A to a table in database B. The datatable holds approximately 5M rows. I have written the following code:



      connection = make_connection(source_db)
      
c = connection.cursor()
      
batch_size = 100000
      
while True:
      
    batch = c.fetchmany(batch_size)
      
    print('Extracted a batch.')
      
    if not batch:
      
        break
      
    insert_data(batch)
      

      
connection.close()


      I ran this code and it takes minutes for fetchmany() to extract a single batch. I've tried to use fetchall() without the while True statement but this takes even longer.



      Question: How do I successfully speed up this process/what is the best way to load large select statements into python?






      mysql python-3.x







      share|improve this question















      I have two mysql databases called database A and database B. I want to use python to copy all the data from a table in database A to a table in database B. The datatable holds approximately 5M rows. I have written the following code:



      connection = make_connection(source_db)
      
c = connection.cursor()
      
batch_size = 100000
      
while True:
      
    batch = c.fetchmany(batch_size)
      
    print('Extracted a batch.')
      
    if not batch:
      
        break
      
    insert_data(batch)
      

      
connection.close()


      I ran this code and it takes minutes for fetchmany() to extract a single batch. I've tried to use fetchall() without the while True statement but this takes even longer.



      Question: How do I successfully speed up this process/what is the best way to load large select statements into python?






      mysql python-3.x




      mysql python-3.x






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Nov 8 at 12:38

























      asked Nov 8 at 11:02









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