Add Variables to Tuple

user_107922 0
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I am learning Python and creating a database connection. While trying to add to the DB, I am thinking of creating tuples out of information and then add them to the DB.

What I am Doing: I am taking information from the user and store it in variables. Can I add these variables into a tuple? Can you please help me with the syntax?

Also if there is an efficient way of doing this, please share...

EDIT Let me edit this question a bit...I only need the tuple to enter info into the DB. Once the information is added to the DB, should I delete the tuple? I mean I don't need the tuple anymore.

tuples python
8 Answers

In Python 3, you can use * to create a new tuple of elements from the original tuple along with the new element.

>>> tuple1 = ("foo", "bar")
>>> tuple2 = (*tuple1, "baz")
>>> tuple2
('foo', 'bar', 'baz')

The byte code is almost the same as tuple1 + ("baz",)

Python 3.7.5 (default, Oct 22 2019, 10:35:10) 
[Clang 10.0.1 (clang-1001.0.46.4)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> def f():
...     tuple1 = ("foo", "bar")
...     tuple2 = (*tuple1, "baz")
...     return tuple2
... 
>>> def g():
...     tuple1 = ("foo", "bar")
...     tuple2 = tuple1 + ("baz",)
...     return tuple2
... 
>>> from dis import dis
>>> dis(f)
  2           0 LOAD_CONST               1 (('foo', 'bar'))
              2 STORE_FAST               0 (tuple1)

  3           4 LOAD_FAST                0 (tuple1)
              6 LOAD_CONST               3 (('baz',))
              8 BUILD_TUPLE_UNPACK       2
             10 STORE_FAST               1 (tuple2)

  4          12 LOAD_FAST                1 (tuple2)
             14 RETURN_VALUE
>>> dis(g)
  2           0 LOAD_CONST               1 (('foo', 'bar'))
              2 STORE_FAST               0 (tuple1)

  3           4 LOAD_FAST                0 (tuple1)
              6 LOAD_CONST               2 (('baz',))
              8 BINARY_ADD
             10 STORE_FAST               1 (tuple2)

  4          12 LOAD_FAST                1 (tuple2)
             14 RETURN_VALUE

The only difference is BUILD_TUPLE_UNPACK vs BINARY_ADD. The exact performance depends on the Python interpreter implementation, but it's natural to implement BUILD_TUPLE_UNPACK faster than BINARY_ADD because BINARY_ADD is a polymorphic operator, requiring additional type calculation and implicit conversion.

user_9550910
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