python - How to open and convert sqlite database to pandas dataframe

Question

I have downloaded some datas as a sqlite database (data.db) and I want to open this database in python and then convert it into pandas dataframe.

This is so far I have done

import sqlite3
import pandas    
dat = sqlite3.connect('data.db') #connected to database with out error
pandas.DataFrame.from_records(dat, index=None, exclude=None, columns=None, coerce_float=False, nrows=None)

But its throwing this error

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/dist-packages/pandas/core/frame.py", line 980, in from_records
    coerce_float=coerce_float)
  File "/usr/local/lib/python2.7/dist-packages/pandas/core/frame.py", line 5353, in _to_arrays
    if not len(data):
TypeError: object of type 'sqlite3.Connection' has no len()

How to convert sqlite database to pandas dataframe

Answer 1

Despite sqlite being part of the Python Standard Library and is a nice and easy interface to SQLite databases, the Pandas tutorial states:

Note In order to use read_sql_table(), you must have the SQLAlchemy optional dependency installed.

But Pandas still supports sqlite3 access if you want to avoid installing SQLAlchemy:

import sqlite3
import pandas as pd
# Create your connection.
cnx = sqlite3.connect('file.db')

df = pd.read_sql_query("SELECT * FROM table_name", cnx)

As stated here, but you need to know the name of the used table in advance.