Serhiy Storchaka added the comment:

Yes, above microbenchmarks measure the time of execute() + the time of fetching 
one row. Here is more precise microbenchmarks.
$ ./python -m timeit -s "import sqlite3; con = sqlite3.connect(':memory:'); 
con.execute('create table t (a, b)')" -s "for i in range(100): 
con.execute('insert into t values (1, 2)')" -- "con.execute('select * from 
t').fetchall()"
1000 loops, best of 3: 624 usec per loop

$ ./python -m timeit -s "import sqlite3; con = sqlite3.connect(':memory:'); 
con.row_factory = sqlite3.Row; con.execute('create table t (a, b)')" -s "for i 
in range(100): con.execute('insert into t values (1, 2)')" -- 
"con.execute('select * from t').fetchall()"
1000 loops, best of 3: 915 usec per loop

$ ./python -m timeit -s "import sqlite3; con = sqlite3.connect(':memory:'); 
con.row_factory = sqlite3.NamedTupleRow; con.execute('create table t (a, b)')" 
-s "for i in range(100): con.execute('insert into t values (1, 2)')" -- 
"con.execute('select * from t').fetchall()"
100 loops, best of 3: 6.21 msec per loop

Here sqlite3.Row is about 1.5 times slower than tuple, but 
sqlite3.NamedTupleRow is about 7 times slower than sqlite3.Row.

With C implementation of lru_cache() (issue14373) the result is much better:

100 loops, best of 3: 3.16 msec per loop

And it will be even more faster (up to 1.7x) when add to the Cursor class a 
method which returns a tuple of field names.

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<http://bugs.python.org/issue13299>
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