Python cx_Oracle.TIMESTAMP Examples

def __init__(self, param, cursor, strings_only=False):
        # With raw SQL queries, datetimes can reach this function
        # without being converted by DateTimeField.get_db_prep_value.
        if settings.USE_TZ and (isinstance(param, datetime.datetime) and
                                not isinstance(param, Oracle_datetime)):
            param = Oracle_datetime.from_datetime(param)

        string_size = 0
        # Oracle doesn't recognize True and False correctly.
        if param is True:
            param = 1
        elif param is False:
            param = 0
        if hasattr(param, 'bind_parameter'):
            self.force_bytes = param.bind_parameter(cursor)
        elif isinstance(param, (Database.Binary, datetime.timedelta)):
            self.force_bytes = param
        else:
            # To transmit to the database, we need Unicode if supported
            # To get size right, we must consider bytes.
            self.force_bytes = force_text(param, cursor.charset, strings_only)
            if isinstance(self.force_bytes, str):
                # We could optimize by only converting up to 4000 bytes here
                string_size = len(force_bytes(param, cursor.charset, strings_only))
        if hasattr(param, 'input_size'):
            # If parameter has `input_size` attribute, use that.
            self.input_size = param.input_size
        elif string_size > 4000:
            # Mark any string param greater than 4000 characters as a CLOB.
            self.input_size = Database.CLOB
        elif isinstance(param, datetime.datetime):
            self.input_size = Database.TIMESTAMP
        else:
            self.input_size = None 

def preQuery(self, cursor):
        typeMap = {"integer": cx_Oracle.NUMBER,
                   "text": cx_Oracle.NCLOB,
                   "varchar": cx_Oracle.STRING,
                   "timestamp": cx_Oracle.TIMESTAMP}
        self.var = cursor.var(typeMap[self.typeID])
        return self.var 

def mapArgs(self, args):
        realArgs = []
        for arg in args:
            if isinstance(arg, str):
                # We use NCLOB everywhere, so cx_Oracle requires a unicode-type
                # input.  But we mostly pass around utf-8 encoded bytes at the
                # application layer as they consume less memory, so do the
                # conversion here.
                arg = arg.decode('utf-8')

            if isinstance(arg, unicode) and len(arg) > 1024:
                # This *may* cause a type mismatch, but none of the non-CLOB
                # strings that we're passing would allow a value this large
                # anyway.  Smaller strings will be automatically converted by
                # the bindings; larger ones will generate an error.  I'm not
                # sure why cx_Oracle itself doesn't just do the following hack
                # automatically and internally for larger values too, but, here
                # it is:
                v = self.var(cx_Oracle.NCLOB, len(arg) + 1)
                v.setvalue(0, arg)

            elif isinstance(arg, datetime.datetime):
                # By default when cx_Oracle is passed a datetime object it maps it to a
                # cx_Oracle.DATETIME variable which does not serialize fraction seconds
                # into the query, or call, arguments. However, for high volume systems,
                # we really want sub-second resolution for things like the job queue,
                # so we want to serialize datetime as cx_Oracle.TIMESTAMP.
                v = self.var(cx_Oracle.TIMESTAMP)
                v.setvalue(0, arg)

            else:
                v = arg

            realArgs.append(v)

        return realArgs 

def convert_values(self, value, field):
        if isinstance(value, Database.LOB):
            value = value.read()
            if field and field.get_internal_type() == 'TextField':
                value = force_text(value)

        # Oracle stores empty strings as null. We need to undo this in
        # order to adhere to the Django convention of using the empty
        # string instead of null, but only if the field accepts the
        # empty string.
        if value is None and field and field.empty_strings_allowed:
            value = ''
        # Convert 1 or 0 to True or False
        elif value in (1, 0) and field and field.get_internal_type() in ('BooleanField', 'NullBooleanField'):
            value = bool(value)
        # Force floats to the correct type
        elif value is not None and field and field.get_internal_type() == 'FloatField':
            value = float(value)
        # Convert floats to decimals
        elif value is not None and field and field.get_internal_type() == 'DecimalField':
            value = util.typecast_decimal(field.format_number(value))
        # cx_Oracle always returns datetime.datetime objects for
        # DATE and TIMESTAMP columns, but Django wants to see a
        # python datetime.date, .time, or .datetime.  We use the type
        # of the Field to determine which to cast to, but it's not
        # always available.
        # As a workaround, we cast to date if all the time-related
        # values are 0, or to time if the date is 1/1/1900.
        # This could be cleaned a bit by adding a method to the Field
        # classes to normalize values from the database (the to_python
        # method is used for validation and isn't what we want here).
        elif isinstance(value, Database.Timestamp):
            if field and field.get_internal_type() == 'DateTimeField':
                pass
            elif field and field.get_internal_type() == 'DateField':
                value = value.date()
            elif field and field.get_internal_type() == 'TimeField' or (value.year == 1900 and value.month == value.day == 1):
                value = value.time()
            elif value.hour == value.minute == value.second == value.microsecond == 0:
                value = value.date()
        return value 

def _rowfactory(row, cursor):
    # Cast numeric values as the appropriate Python type based upon the
    # cursor description, and convert strings to unicode.
    casted = []
    for value, desc in zip(row, cursor.description):
        if value is not None and desc[1] is Database.NUMBER:
            precision, scale = desc[4:6]
            if scale == -127:
                if precision == 0:
                    # NUMBER column: decimal-precision floating point
                    # This will normally be an integer from a sequence,
                    # but it could be a decimal value.
                    if '.' in value:
                        value = decimal.Decimal(value)
                    else:
                        value = int(value)
                else:
                    # FLOAT column: binary-precision floating point.
                    # This comes from FloatField columns.
                    value = float(value)
            elif precision > 0:
                # NUMBER(p,s) column: decimal-precision fixed point.
                # This comes from IntField and DecimalField columns.
                if scale == 0:
                    value = int(value)
                else:
                    value = decimal.Decimal(value)
            elif '.' in value:
                # No type information. This normally comes from a
                # mathematical expression in the SELECT list. Guess int
                # or Decimal based on whether it has a decimal point.
                value = decimal.Decimal(value)
            else:
                value = int(value)
        # datetimes are returned as TIMESTAMP, except the results
        # of "dates" queries, which are returned as DATETIME.
        elif desc[1] in (Database.TIMESTAMP, Database.DATETIME):
            # Confirm that dt is naive before overwriting its tzinfo.
            if settings.USE_TZ and value is not None and timezone.is_naive(value):
                value = value.replace(tzinfo=timezone.utc)
        elif desc[1] in (Database.STRING, Database.FIXED_CHAR,
                         Database.LONG_STRING):
            value = to_unicode(value)
        casted.append(value)
    return tuple(casted) 

def _rowfactory(row, cursor):
    # Cast numeric values as the appropriate Python type based upon the
    # cursor description, and convert strings to unicode.
    casted = []
    for value, desc in zip(row, cursor.description):
        if value is not None and desc[1] is Database.NUMBER:
            precision, scale = desc[4:6]
            if scale == -127:
                if precision == 0:
                    # NUMBER column: decimal-precision floating point
                    # This will normally be an integer from a sequence,
                    # but it could be a decimal value.
                    if '.' in value:
                        value = decimal.Decimal(value)
                    else:
                        value = int(value)
                else:
                    # FLOAT column: binary-precision floating point.
                    # This comes from FloatField columns.
                    value = float(value)
            elif precision > 0:
                # NUMBER(p,s) column: decimal-precision fixed point.
                # This comes from IntField and DecimalField columns.
                if scale == 0:
                    value = int(value)
                else:
                    value = decimal.Decimal(value)
            elif '.' in value:
                # No type information. This normally comes from a
                # mathematical expression in the SELECT list. Guess int
                # or Decimal based on whether it has a decimal point.
                value = decimal.Decimal(value)
            else:
                value = int(value)
        # datetimes are returned as TIMESTAMP, except the results
        # of "dates" queries, which are returned as DATETIME.
        elif desc[1] in (Database.TIMESTAMP, Database.DATETIME):
            # Confirm that dt is naive before overwriting its tzinfo.
            if settings.USE_TZ and value is not None and timezone.is_naive(value):
                value = value.replace(tzinfo=timezone.utc)
        elif desc[1] in (Database.STRING, Database.FIXED_CHAR,
                         Database.LONG_STRING):
            value = to_unicode(value)
        casted.append(value)
    return tuple(casted) 

def __init__(self,
                 auto_convert_lobs=True,
                 threaded=True,
                 coerce_to_unicode=False,
                 coerce_to_decimal=True,
                 arraysize=50,
                 **kwargs):

        self._pop_deprecated_kwargs(kwargs)

        OracleDialect.__init__(self, **kwargs)
        self.threaded = threaded
        self.arraysize = arraysize
        self.auto_convert_lobs = auto_convert_lobs
        self.coerce_to_unicode = coerce_to_unicode
        self.coerce_to_decimal = coerce_to_decimal

        cx_Oracle = self.dbapi

        if cx_Oracle is None:
            self._include_setinputsizes = {}
            self.cx_oracle_ver = (0, 0, 0)
        else:
            self.cx_oracle_ver = self._parse_cx_oracle_ver(cx_Oracle.version)
            if self.cx_oracle_ver < (5, 2) and self.cx_oracle_ver > (0, 0, 0):
                raise exc.InvalidRequestError(
                    "cx_Oracle version 5.2 and above are supported")

            self._has_native_int = hasattr(cx_Oracle, "NATIVE_INT")

            self._include_setinputsizes = {
                cx_Oracle.NCLOB, cx_Oracle.CLOB, cx_Oracle.LOB,
                cx_Oracle.NCHAR, cx_Oracle.FIXED_NCHAR,
                cx_Oracle.BLOB, cx_Oracle.FIXED_CHAR, cx_Oracle.TIMESTAMP,
                _OracleInteger, _OracleBINARY_FLOAT, _OracleBINARY_DOUBLE
            }

            self._paramval = lambda value: value.getvalue()

            # https://github.com/oracle/python-cx_Oracle/issues/176#issuecomment-386821291
            # https://github.com/oracle/python-cx_Oracle/issues/224
            self._values_are_lists = self.cx_oracle_ver >= (6, 3)
            if self._values_are_lists:
                cx_Oracle.__future__.dml_ret_array_val = True

                def _returningval(value):
                    try:
                        return value.values[0][0]
                    except IndexError:
                        return None

                self._returningval = _returningval
            else:
                self._returningval = self._paramval

        self._is_cx_oracle_6 = self.cx_oracle_ver >= (6, )