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?










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    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?










    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?










      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






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      edited Nov 8 at 12:38

























      asked Nov 8 at 11:02









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