|
| 1 | +import re |
| 2 | + |
| 3 | +from .database_types import * |
| 4 | +from .base import Database, import_helper |
| 5 | +from .base import ( |
| 6 | + MD5_HEXDIGITS, |
| 7 | + CHECKSUM_HEXDIGITS, |
| 8 | + TIMESTAMP_PRECISION_POS, |
| 9 | + DEFAULT_DATETIME_PRECISION, |
| 10 | +) |
| 11 | + |
| 12 | + |
| 13 | +@import_helper("trino") |
| 14 | +def import_trino(): |
| 15 | + import trino |
| 16 | + |
| 17 | + return trino |
| 18 | + |
| 19 | + |
| 20 | +class Trino(Database): |
| 21 | + default_schema = "public" |
| 22 | + TYPE_CLASSES = { |
| 23 | + # Timestamps |
| 24 | + "timestamp with time zone": TimestampTZ, |
| 25 | + "timestamp without time zone": Timestamp, |
| 26 | + "timestamp": Timestamp, |
| 27 | + # Numbers |
| 28 | + "integer": Integer, |
| 29 | + "bigint": Integer, |
| 30 | + "real": Float, |
| 31 | + "double": Float, |
| 32 | + # Text |
| 33 | + "varchar": Text, |
| 34 | + } |
| 35 | + ROUNDS_ON_PREC_LOSS = True |
| 36 | + |
| 37 | + def __init__(self, **kw): |
| 38 | + trino = import_trino() |
| 39 | + |
| 40 | + self._conn = trino.dbapi.connect(**kw) |
| 41 | + |
| 42 | + def quote(self, s: str): |
| 43 | + return f'"{s}"' |
| 44 | + |
| 45 | + def md5_to_int(self, s: str) -> str: |
| 46 | + return f"cast(from_base(substr(to_hex(md5(to_utf8({s}))), {1 + MD5_HEXDIGITS - CHECKSUM_HEXDIGITS}), 16) as decimal(38, 0))" |
| 47 | + |
| 48 | + def to_string(self, s: str): |
| 49 | + return f"cast({s} as varchar)" |
| 50 | + |
| 51 | + def _query(self, sql_code: str) -> list: |
| 52 | + """Uses the standard SQL cursor interface""" |
| 53 | + c = self._conn.cursor() |
| 54 | + c.execute(sql_code) |
| 55 | + if sql_code.lower().startswith("select"): |
| 56 | + return c.fetchall() |
| 57 | + |
| 58 | + def close(self): |
| 59 | + self._conn.close() |
| 60 | + |
| 61 | + def normalize_timestamp(self, value: str, coltype: TemporalType) -> str: |
| 62 | + if coltype.rounds: |
| 63 | + s = f"date_format(cast({coltype.precision} as timestamp(6)), '%Y-%m-%d %H:%i:%S.%f')" |
| 64 | + else: |
| 65 | + s = f"date_format(cast({value} as timestamp(6)), '%Y-%m-%d %H:%i:%S.%f')" |
| 66 | + |
| 67 | + return f"RPAD(RPAD({s}, {TIMESTAMP_PRECISION_POS + coltype.precision}, '.'), {TIMESTAMP_PRECISION_POS + 6}, '0')" |
| 68 | + |
| 69 | + def normalize_number(self, value: str, coltype: FractionalType) -> str: |
| 70 | + return self.to_string(f"cast({value} as decimal(38,{coltype.precision}))") |
| 71 | + |
| 72 | + def select_table_schema(self, path: DbPath) -> str: |
| 73 | + schema, table = self._normalize_table_path(path) |
| 74 | + |
| 75 | + return ( |
| 76 | + f"SELECT column_name, data_type, 3 as datetime_precision, 3 as numeric_precision FROM INFORMATION_SCHEMA.COLUMNS " |
| 77 | + f"WHERE table_name = '{table}' AND table_schema = '{schema}'" |
| 78 | + ) |
| 79 | + |
| 80 | + def _parse_type( |
| 81 | + self, |
| 82 | + table_path: DbPath, |
| 83 | + col_name: str, |
| 84 | + type_repr: str, |
| 85 | + datetime_precision: int = None, |
| 86 | + numeric_precision: int = None, |
| 87 | + ) -> ColType: |
| 88 | + timestamp_regexps = { |
| 89 | + r"timestamp\((\d)\)": Timestamp, |
| 90 | + r"timestamp\((\d)\) with time zone": TimestampTZ, |
| 91 | + } |
| 92 | + for regexp, t_cls in timestamp_regexps.items(): |
| 93 | + m = re.match(regexp + "$", type_repr) |
| 94 | + if m: |
| 95 | + datetime_precision = int(m.group(1)) |
| 96 | + return t_cls( |
| 97 | + precision=datetime_precision |
| 98 | + if datetime_precision is not None |
| 99 | + else DEFAULT_DATETIME_PRECISION, |
| 100 | + rounds=self.ROUNDS_ON_PREC_LOSS, |
| 101 | + ) |
| 102 | + |
| 103 | + number_regexps = {r"decimal\((\d+),(\d+)\)": Decimal} |
| 104 | + for regexp, n_cls in number_regexps.items(): |
| 105 | + m = re.match(regexp + "$", type_repr) |
| 106 | + if m: |
| 107 | + prec, scale = map(int, m.groups()) |
| 108 | + return n_cls(scale) |
| 109 | + |
| 110 | + string_regexps = {r"varchar\((\d+)\)": Text, r"char\((\d+)\)": Text} |
| 111 | + for regexp, n_cls in string_regexps.items(): |
| 112 | + m = re.match(regexp + "$", type_repr) |
| 113 | + if m: |
| 114 | + return n_cls() |
| 115 | + |
| 116 | + return super()._parse_type( |
| 117 | + table_path, col_name, type_repr, datetime_precision, numeric_precision |
| 118 | + ) |
| 119 | + |
| 120 | + def normalize_uuid(self, value: str, coltype: ColType_UUID) -> str: |
| 121 | + return f"TRIM({value})" |
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