sqlalchemy update using list of tuples - sqlalchemy

Question

Is there an efficient way to update rows based on list of tuples in sqlalchemy?
If its a single row, then I can simply do:
session.query(table).filter(table.id == 10).update({'values': 'x'})
session.commit
however, the data i'm getting is a list of tuples
[(10, 'x'),(20,'y'),(30,'z'),(40,'p')]
table has IDs 10,20,30,40 etc.
is there efficient way to update instead of multiple individual updates?

Answer 1

You can convert the list of tuples to a list of dicts and then use update() with bindparam() as illustrated in the tutorial:
from pprint import pprint
import sqlalchemy as sa
engine = sa.create_engine("sqlite://")
tbl = sa.Table(
"tbl",
sa.MetaData(),
sa.Column("id", sa.Integer, primary_key=True, autoincrement=False),
sa.Column("value", sa.String(50)),
)
tbl.create(engine)
with engine.begin() as conn:
conn.execute(
tbl.insert(),
[
{"id": 10, "value": "old_10"},
{"id": 20, "value": "old_20"},
{"id": 30, "value": "old_30"},
],
)
with engine.begin() as conn:
# initial state
print(conn.execute(sa.select(tbl)).all())
# [(10, 'old_10'), (20, 'old_20'), (30, 'old_30')]
new_data = [(10, "x"), (20, "y"), (30, "z")]
params = [dict(tbl_id=a, new_value=b) for (a, b) in new_data]
pprint(params, sort_dicts=False)
"""
[{'tbl_id': 10, 'new_value': 'x'},
{'tbl_id': 20, 'new_value': 'y'},
{'tbl_id': 30, 'new_value': 'z'}]
"""
upd = (
sa.update(tbl)
.values(value=sa.bindparam("new_value"))
.where(tbl.c.id == sa.bindparam("tbl_id"))
)
print(upd)
# UPDATE tbl SET value=:new_value WHERE tbl.id = :tbl_id
conn.execute(upd, params)
# check results
print(conn.execute(sa.select(tbl)).all())
# [(10, 'x'), (20, 'y'), (30, 'z')]