Concatenate a list of pandas dataframes together

I have a list of Pandas dataframes that I would like to combine into one Pandas dataframe. I am using Python 2.7.10 and Pandas 0.16.2

I created the list of dataframes from:

    import pandas as pd
    dfs = []
    sqlall = "select * from mytable"

    for chunk in pd.read_sql_query(sqlall , cnxn, chunksize=10000):
        dfs.append(chunk)

This returns a list of dataframes

    type(dfs[0])
    Out[6]: pandas.core.frame.DataFrame

    type(dfs)
    Out[7]: list

    len(dfs)
    Out[8]: 408

Here is some sample data

    # sample dataframes
    d1 = pd.DataFrame({'one' : [1., 2., 3., 4.], 'two' : [4., 3., 2., 1.]})
    d2 = pd.DataFrame({'one' : [5., 6., 7., 8.], 'two' : [9., 10., 11., 12.]})
    d3 = pd.DataFrame({'one' : [15., 16., 17., 18.], 'two' : [19., 10., 11., 12.]})

    # list of dataframes
    mydfs = [d1, d2, d3]

I would like to combine d1, d2, and d3 into one pandas dataframe. Alternatively, a method of reading a large-ish table directly into a dataframe when using the chunksize option would be very helpful.

Given that all the dataframes have the same columns, you can simply concat them:

    import pandas as pd
    df = pd.concat(list_of_dataframes)

From: stackoverflow.com/q/32444138