|
| 1 | +import datetime |
| 2 | +import logging |
| 3 | +import argparse |
| 4 | +import sqlalchemy as sa |
| 5 | +from sqlalchemy import orm, exc, sql |
| 6 | +from sqlalchemy import Table, Column, Integer, String, Float, TIMESTAMP |
| 7 | +from ydb._sqlalchemy import register_dialect |
| 8 | + |
| 9 | +from fill_tables import fill_all_tables, to_days |
| 10 | +from models import Base, Series, Episodes |
| 11 | + |
| 12 | + |
| 13 | +def describe_table(engine, name): |
| 14 | + inspect = sa.inspect(engine) |
| 15 | + print(f"describe table {name}:") |
| 16 | + for col in inspect.get_columns(name): |
| 17 | + print(f"\t{col['name']}: {col['type']}") |
| 18 | + |
| 19 | + |
| 20 | +def simple_select(conn): |
| 21 | + stm = sa.select(Series).where(Series.series_id == 1) |
| 22 | + res = conn.execute(stm) |
| 23 | + print(res.one()) |
| 24 | + |
| 25 | + |
| 26 | +def simple_insert(conn): |
| 27 | + stm = Episodes.__table__.insert().values( |
| 28 | + series_id=3, season_id=6, episode_id=1, title="TBD" |
| 29 | + ) |
| 30 | + conn.execute(stm) |
| 31 | + |
| 32 | + |
| 33 | +def test_types(conn): |
| 34 | + types_tb = Table( |
| 35 | + "test_types", |
| 36 | + Base.metadata, |
| 37 | + Column("id", Integer, primary_key=True), |
| 38 | + Column("str", String), |
| 39 | + Column("num", Float), |
| 40 | + Column("dt", TIMESTAMP), |
| 41 | + ) |
| 42 | + types_tb.drop(bind=conn.engine, checkfirst=True) |
| 43 | + types_tb.create(bind=conn.engine, checkfirst=True) |
| 44 | + |
| 45 | + stm = types_tb.insert().values( |
| 46 | + id=1, |
| 47 | + str=b"Hello World!", |
| 48 | + num=3.1415, |
| 49 | + dt=datetime.datetime.now(), |
| 50 | + ) |
| 51 | + conn.execute(stm) |
| 52 | + |
| 53 | + # GROUP BY |
| 54 | + stm = sa.select(types_tb.c.str, sa.func.max(types_tb.c.num)).group_by( |
| 55 | + types_tb.c.str |
| 56 | + ) |
| 57 | + rs = conn.execute(stm) |
| 58 | + for x in rs: |
| 59 | + print(x) |
| 60 | + |
| 61 | + |
| 62 | +def run_example_orm(engine): |
| 63 | + Base.metadata.bind = engine |
| 64 | + Base.metadata.drop_all() |
| 65 | + Base.metadata.create_all() |
| 66 | + |
| 67 | + session = orm.sessionmaker(bind=engine)() |
| 68 | + |
| 69 | + rs = session.query(Episodes).all() |
| 70 | + for e in rs: |
| 71 | + print(f"{e.episode_id}: {e.title}") |
| 72 | + |
| 73 | + fill_all_tables(session.connection()) |
| 74 | + |
| 75 | + try: |
| 76 | + session.add_all( |
| 77 | + [ |
| 78 | + Episodes( |
| 79 | + series_id=2, |
| 80 | + season_id=1, |
| 81 | + episode_id=1, |
| 82 | + title="Minimum Viable Product", |
| 83 | + air_date=to_days("2014-04-06"), |
| 84 | + ), |
| 85 | + Episodes( |
| 86 | + series_id=2, |
| 87 | + season_id=1, |
| 88 | + episode_id=2, |
| 89 | + title="The Cap Table", |
| 90 | + air_date=to_days("2014-04-13"), |
| 91 | + ), |
| 92 | + Episodes( |
| 93 | + series_id=2, |
| 94 | + season_id=1, |
| 95 | + episode_id=3, |
| 96 | + title="Articles of Incorporation", |
| 97 | + air_date=to_days("2014-04-20"), |
| 98 | + ), |
| 99 | + Episodes( |
| 100 | + series_id=2, |
| 101 | + season_id=1, |
| 102 | + episode_id=4, |
| 103 | + title="Fiduciary Duties", |
| 104 | + air_date=to_days("2014-04-27"), |
| 105 | + ), |
| 106 | + Episodes( |
| 107 | + series_id=2, |
| 108 | + season_id=1, |
| 109 | + episode_id=5, |
| 110 | + title="Signaling Risk", |
| 111 | + air_date=to_days("2014-05-04"), |
| 112 | + ), |
| 113 | + ] |
| 114 | + ) |
| 115 | + session.commit() |
| 116 | + except exc.DatabaseError: |
| 117 | + print("Episodes already added!") |
| 118 | + session.rollback() |
| 119 | + |
| 120 | + rs = session.query(Episodes).all() |
| 121 | + for e in rs: |
| 122 | + print(f"{e.episode_id}: {e.title}") |
| 123 | + |
| 124 | + rs = session.query(Episodes).filter(Episodes.title == "abc??").all() |
| 125 | + for e in rs: |
| 126 | + print(e.title) |
| 127 | + |
| 128 | + print("Episodes count:", session.query(Episodes).count()) |
| 129 | + |
| 130 | + max_episode = session.query(sql.expression.func.max(Episodes.episode_id)).scalar() |
| 131 | + print("Maximum episodes id:", max_episode) |
| 132 | + |
| 133 | + session.add( |
| 134 | + Episodes( |
| 135 | + series_id=2, |
| 136 | + season_id=1, |
| 137 | + episode_id=max_episode + 1, |
| 138 | + title="Signaling Risk", |
| 139 | + air_date=to_days("2014-05-04"), |
| 140 | + ) |
| 141 | + ) |
| 142 | + |
| 143 | + print("Episodes count:", session.query(Episodes).count()) |
| 144 | + |
| 145 | + |
| 146 | +def run_example_core(engine): |
| 147 | + with engine.connect() as conn: |
| 148 | + # raw sql |
| 149 | + rs = conn.execute("SELECT 1 AS value") |
| 150 | + print(rs.fetchone()["value"]) |
| 151 | + |
| 152 | + fill_all_tables(conn) |
| 153 | + |
| 154 | + for t in "series seasons episodes".split(): |
| 155 | + describe_table(engine, t) |
| 156 | + |
| 157 | + tb = sa.Table("episodes", sa.MetaData(engine), autoload=True) |
| 158 | + stm = ( |
| 159 | + sa.select([tb.c.title]) |
| 160 | + .where(sa.and_(tb.c.series_id == 1, tb.c.season_id == 3)) |
| 161 | + .where(tb.c.title.like("%")) |
| 162 | + .order_by(sa.asc(tb.c.title)) |
| 163 | + # TODO: limit isn't working now |
| 164 | + # .limit(3) |
| 165 | + ) |
| 166 | + rs = conn.execute(stm) |
| 167 | + print(rs.fetchall()) |
| 168 | + |
| 169 | + simple_select(conn) |
| 170 | + |
| 171 | + simple_insert(conn) |
| 172 | + |
| 173 | + # simple join |
| 174 | + stm = sa.select( |
| 175 | + [Episodes.__table__.join(Series, Episodes.series_id == Series.series_id)] |
| 176 | + ).where(sa.and_(Series.series_id == 1, Episodes.season_id == 1)) |
| 177 | + rs = conn.execute(stm) |
| 178 | + for row in rs: |
| 179 | + print(f"{row.series_title}({row.episode_id}): {row.title}") |
| 180 | + |
| 181 | + rs = conn.execute(sa.select(Episodes).where(Episodes.series_id == 3)) |
| 182 | + print(rs.fetchall()) |
| 183 | + |
| 184 | + # count |
| 185 | + cnt = conn.execute(sa.func.count(Episodes.episode_id)).scalar() |
| 186 | + print("Episodes cnt:", cnt) |
| 187 | + |
| 188 | + # simple delete |
| 189 | + conn.execute(sa.delete(Episodes).where(Episodes.title == "TBD")) |
| 190 | + cnt = conn.execute(sa.func.count(Episodes.episode_id)).scalar() |
| 191 | + print("Episodes cnt:", cnt) |
| 192 | + |
| 193 | + test_types(conn) |
| 194 | + |
| 195 | + |
| 196 | +def main(): |
| 197 | + parser = argparse.ArgumentParser( |
| 198 | + formatter_class=argparse.RawDescriptionHelpFormatter, |
| 199 | + description="""\033[92mYandex.Database examples sqlalchemy usage.\x1b[0m\n""", |
| 200 | + ) |
| 201 | + parser.add_argument( |
| 202 | + "-d", |
| 203 | + "--database", |
| 204 | + help="Name of the database to use", |
| 205 | + default="/local", |
| 206 | + ) |
| 207 | + parser.add_argument( |
| 208 | + "-e", |
| 209 | + "--endpoint", |
| 210 | + help="Endpoint url to use", |
| 211 | + default="grpc://localhost:2136", |
| 212 | + ) |
| 213 | + |
| 214 | + args = parser.parse_args() |
| 215 | + register_dialect() |
| 216 | + engine = sa.create_engine( |
| 217 | + "yql:///ydb/", |
| 218 | + connect_args={"database": args.database, "endpoint": args.endpoint}, |
| 219 | + ) |
| 220 | + |
| 221 | + logging.basicConfig(level=logging.INFO) |
| 222 | + logging.getLogger("_sqlalchemy.engine").setLevel(logging.INFO) |
| 223 | + |
| 224 | + run_example_core(engine) |
| 225 | + # run_example_orm(engine) |
| 226 | + |
| 227 | + |
| 228 | +if __name__ == "__main__": |
| 229 | + main() |
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