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# RECIPE CATEGORY: PostgreSQL
# RECIPE KEYWORDS: bulk ingestion to temporary table
# RECIPE STARTS HERE
#: ADBC allows creating and appending to temporary tables as well.

import os

import pyarrow

from adbc_driver_manager import dbapi

uri = os.environ["ADBC_POSTGRESQL_TEST_URI"]
conn = dbapi.connect("postgresql", uri)

#: For the purposes of testing, we'll first make sure the tables we're about
#: to use don't exist.
with conn.cursor() as cur:
    cur.execute("DROP TABLE IF EXISTS example")

#: To create a temporary table, just specify the option "temporary".
data = pyarrow.table(
    [
        [1, 2, None, 4],
    ],
    schema=pyarrow.schema(
        [
            ("ints", "int32"),
        ]
    ),
)

with conn.cursor() as cur:
    cur.adbc_ingest("example", data, mode="create", temporary=True)

conn.commit()

#: After ingestion, we can fetch the result.
with conn.cursor() as cur:
    cur.execute("SELECT * FROM example")
    assert cur.fetchone() == (1,)
    assert cur.fetchone() == (2,)

    cur.execute("SELECT COUNT(*) FROM example")
    assert cur.fetchone() == (4,)

#: Temporary tables are separate from regular tables, even if they have the
#: same name.

with conn.cursor() as cur:
    cur.adbc_ingest("example", data.slice(0, 2), mode="create", temporary=False)

conn.commit()

with conn.cursor() as cur:
    #: Because we have two tables with the same name, we have to explicitly
    #: reference the normal temporary table here.
    cur.execute("SELECT COUNT(*) FROM public.example")
    assert cur.fetchone() == (2,)

    cur.execute("SELECT COUNT(*) FROM example")
    assert cur.fetchone() == (4,)

conn.close()

#: After closing the connection, the temporary table is implicitly dropped.
#: If we reconnect, the table won't exist; we'll see only the 'normal' table.

with dbapi.connect("postgresql", uri) as conn:
    with conn.cursor() as cur:
        cur.execute("SELECT COUNT(*) FROM example")
        assert cur.fetchone() == (2,)

#: All the regular ingestion options apply to temporary tables, too.  See
#: :ref:`recipe-postgresql-create-append` for more examples.