def test_rename_table():
db = ItemDB(":memory:")
db.ensure_table("persons", "!name")
with db:
db.put_one("persons", name="Jan", age=30)
db.put_one("persons", name="Henk", age=42)
db.put_one("persons", name="Takkie", age=30)
db.put_one("persons", name="Siepe", age=42)
assert db.count_all("persons") == 4
with raises(KeyError):
db.count_all("clients")
# Fails
with raises(IOError): # Need a transaction context
db.rename_table("persons", "clients")
with raises(TypeError): # not a str
with db:
db.rename_table("persons", 3)
with raises(TypeError): # not an identifier
with db:
db.rename_table("persons", "foo bar")
with db:
db.rename_table("persons", "clients")
assert db.count_all("clients") == 4
with raises(KeyError):
db.count_all("persons")
def test_change_unique_key():
db = ItemDB(":memory:")
db.ensure_table("persons", "!name")
with db:
db.put_one("persons", name="Jan", age=30)
db.put_one("persons", name="Henk", age=42)
assert db.count_all("persons") == 2
# Add a new person, who also happens to be named "Jan"
with db:
db.put_one("persons", name="Jan", age=72)
# Sorry, Jan
assert db.count_all("persons") == 2
# Let's fix this, we need a separate id, so we need to re-index.
# We cannot simply do this on an existing table. So we need some steps.
try:
with db:
db.ensure_table("persons2")
for i, person in enumerate(db.select_all("persons")):
person["id"] = i
db.put("persons2", person)
db.delete_table("persons")
raise RuntimeError("Oop! Something goes wrong in the process")
db.rename_table("persons2", "persons")
except RuntimeError:
pass
# Our little operation failed, but we did it in a transaction, so its fine!
assert db.count_all("persons") == 2
# Try again
with db:
db.ensure_table("persons2")
for i, person in enumerate(db.select_all("persons")):
person["id"] = i
db.put("persons2", person)
db.delete_table("persons")
db.rename_table("persons2", "persons")
# Now we're good
assert db.count_all("persons") == 2
with db:
db.put_one("persons", name="Jan", age=72, id=3)
assert db.count_all("persons") == 3