Python：从sqlite3中提取文本作为字符串

Question

First week programming in any language and need some help: Im trying to extract a TEXT value as a string from sqlite3 in Python. Im getting a value as a list not a str:

system_id = raw_input ("What is your System ID: ")

For example the user enters 'Elmer'

conn = sqlite3.connect("API.db")
c = conn.cursor()
c.execute('''CREATE TABLE IF NOT EXISTS SYSTEMID (systemid TEXT)''')
conn.commit()
conn.close()

conn = sqlite3.connect("API.db")
c = conn.cursor()
system_id = c.execute('select systemid from SYSTEMID').fetchall()
conn.close()

So how to make the variable system_id as a string? If I print from this I get something like [(u, Elmer)], I want system_id = Elmer

Answer 1

As pointed out by Ev. Kounis , fetchall() by default will return a list of tuple s with length equal to the variables specified.

In your case you are getting a tuple of length 1, because you asked for a single variable.

The u in front of the string 'Elmer' is also returned by default when getting strings (this just means it is a Unicode String).

There are two things you should do:

1. Get rid of u by changing text_factor of the connection to str like this:

    con.text_factory = str 

2. Accessing first element of the tuple to only get the string 'Elmer' :

   fetch = c.execute('select systemid from SYSTEMID').fetchall()
system_id = fetch[0][0] # First element in first tuple in list