If query is a string storing an SQL statement. Write statements so that the data is fetched based on query from SQL database Mydata.

Predict the output of following code fragments one by one. For every next code fragment, consider that the changes by previous code fragment are in place. That is, for code fragment (b), changes made by code fragment (a) are persisting ; for (c), changes by (a) and (b) are persisting and so on.

(a)

import pandas as pd
columns=['2015', '2016', '2017', '2018']
index=['Messi', 'Ronaldo', 'Neymar', 'Hazard']
df = pd.DataFrame(columns = columns, index = index)
print(df)
df.to_csv("c:\one.csv")

(b)

df['2015']['Messi'] = 12 
df['2016']['Ronaldo'] = 11 
df['2017']['Neymar'] = 8 
df['2018']['Hazard'] = 16 
print(df)
df.to_csv("c:\\two.csv", sep = '@')

(c)

new_df = pd.read_csv('c:\one.csv', index_col = 0) 
print(new_df)

(d)

new_df = pd.read_csv('c:\one.csv') 
print(new_df)

(e)

new_df = pd.read_csv('c:\\two.csv') 
print(new_df)

(f)

new_df = pd.read_csv('c:\\two.csv', sep = '@')
print(new_df)

How are following two codes similar or different ? What output will they produce ?

(i)

df = pd.read_csv("data.csv", nrows = 5) 
print(df)

(ii)

df = pd.read_csv("data.csv")
print(df)

Write Python statement to export the DataFrame to a CSV file named data.csv stored at D: drive.