diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/topics/db/sql.txt | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/docs/topics/db/sql.txt b/docs/topics/db/sql.txt index 94a724af04..47a7ea39e1 100644 --- a/docs/topics/db/sql.txt +++ b/docs/topics/db/sql.txt @@ -323,7 +323,10 @@ small performance and memory cost, you can return results as a ``dict`` by using something like this:: def dictfetchall(cursor): - "Return all rows from a cursor as a dict" + """ + Return all rows from a cursor as a dict. + Assume the column names are unique. + """ columns = [col[0] for col in cursor.description] return [dict(zip(columns, row)) for row in cursor.fetchall()] @@ -336,11 +339,17 @@ immutable and accessible by field names or indices, which might be useful:: def namedtuplefetchall(cursor): - "Return all rows from a cursor as a namedtuple" + """ + Return all rows from a cursor as a namedtuple. + Assume the column names are unique. + """ desc = cursor.description nt_result = namedtuple("Result", [col[0] for col in desc]) return [nt_result(*row) for row in cursor.fetchall()] +The ``dictfetchall()`` and ``namedtuplefetchall()`` examples assume unique +column names, since a cursor cannot distinguish columns from different tables. + Here is an example of the difference between the three: .. code-block:: pycon |