django: duration arithmetic fails with dates

[timgraham]

In #209, I made the assumption that DatabaseOperations.combine_duration_expression() operates on TIMESTAMP (TIMESTAMP_ADD and TIMESTAMP_SUB). However, it can also receive a DATE in which case, Spanner crashes as it requires using DATE_ADD / DATE_SUB instead:

======================================================================
ERROR: test_date_minus_duration (expressions.tests.FTimeDeltaTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/api_core/grpc_helpers.py", line 79, in next
    return six.next(self._wrapped)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/grpc/_channel.py", line 392, in __next__
    return self._next()
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/grpc/_channel.py", line 561, in _next
    raise self
grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with:
	status = StatusCode.INVALID_ARGUMENT
	details = "No matching signature for function TIMESTAMP_SUB for argument types: DATE, INTERVAL INT64 DATE_TIME_PART. Supported signature: TIMESTAMP_SUB(TIMESTAMP, INTERVAL INT64 DATE_TIME_PART) [at 1:299]\n...WHERE expressions_ExPeRiMeNt.assigned < ((TIMESTAMP_SUB(expressions_ExPeRi...\n                                             ^"
	debug_error_string = "{"created":"@1576629822.749570417","description":"Error received from peer ipv4:172.217.12.138:443","file":"src/core/lib/surface/call.cc","file_line":1055,"grpc_message":"No matching signature for function TIMESTAMP_SUB for argument types: DATE, INTERVAL INT64 DATE_TIME_PART. Supported signature: TIMESTAMP_SUB(TIMESTAMP, INTERVAL INT64 DATE_TIME_PART) [at 1:299]\n...WHERE expressions_ExPeRiMeNt.assigned < ((TIMESTAMP_SUB(expressions_ExPeRi...\n                                             ^","grpc_status":3}"
>

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/tim/code/django/tests/expressions/tests.py", line 1369, in test_date_minus_duration
    self.assertQuerysetEqual(more_than_4_days, ['e3', 'e4', 'e5'], lambda e: e.name)
  File "/home/tim/code/django/django/test/testcases.py", line 1047, in assertQuerysetEqual
    items = map(transform, qs)
  File "/home/tim/code/django/django/db/models/query.py", line 274, in __iter__
    self._fetch_all()
  File "/home/tim/code/django/django/db/models/query.py", line 1242, in _fetch_all
    self._result_cache = list(self._iterable_class(self))
  File "/home/tim/code/django/django/db/models/query.py", line 55, in __iter__
    results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size)
  File "/home/tim/code/django/django/db/models/sql/compiler.py", line 1166, in execute_sql
    return list(result)
  File "/home/tim/code/django/django/db/models/sql/compiler.py", line 1545, in cursor_iter
    for rows in iter((lambda: cursor.fetchmany(itersize)), sentinel):
  File "/home/tim/code/django/django/db/models/sql/compiler.py", line 1545, in <lambda>
    for rows in iter((lambda: cursor.fetchmany(itersize)), sentinel):
  File "/home/tim/code/django/django/db/utils.py", line 96, in inner
    return func(*args, **kwargs)
  File "/home/tim/code/spanner-orm/spanner/dbapi/cursor.py", line 250, in fetchmany
    items.append(tuple(self.__next__()))
  File "/home/tim/code/spanner-orm/spanner/dbapi/cursor.py", line 213, in __next__
    return next(self.__itr)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/streamed.py", line 143, in __iter__
    self._consume_next()
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/streamed.py", line 116, in _consume_next
    response = six.next(self._response_iterator)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/snapshot.py", line 45, in _restart_on_unavailable
    for item in iterator:
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/api_core/grpc_helpers.py", line 81, in next
    six.raise_from(exceptions.from_grpc_error(exc), exc)
  File "<string>", line 3, in raise_from
google.api_core.exceptions.InvalidArgument: 400 No matching signature for function TIMESTAMP_SUB for argument types: DATE, INTERVAL INT64 DATE_TIME_PART. Supported signature: TIMESTAMP_SUB(TIMESTAMP, INTERVAL INT64 DATE_TIME_PART) [at 1:299]\n...WHERE expressions_ExPeRiMeNt.assigned < ((TIMESTAMP_SUB(expressions_ExPeRi...\n                                             ^

[odeke-em]

Remedy

Just like @timgraham stated in his issue statement:
We should check the type of arguments passed into combine_duration_expression and if it is a models.DateField, we should instead use DATE_ADD or DATE_SUB

Test case

Give an existing database, run this program

#!/usr/bin/env python3

from spanner.dbapi import connect

def tables_map(cursor):
    return {key[0]: True for key in cursor.list_tables()}

def main():
    with connect(project='appdev-soda-spanner-staging', instance='django-tests', database='issues-17') as conn:
        with conn.cursor() as cursor:
            tables = tables_map(cursor)
            table_name = 'Experiment'
            exists = tables.get(table_name, None)
            if False:
                cursor.execute('''DROP TABLE Experiment''')
                exists = False
                conn.commit()

            if not exists:
                cursor.execute('''CREATE TABLE Experiment (
                                    name STRING(24),
                                    id INT64 NOT NULL,
                                    assigned DATE,
                                    completed DATE,
                                    estimated_time INT64,
                                    start TIMESTAMP,
                                    terminate TIMESTAMP
                                ) PRIMARY KEY(id)''')
                conn.commit()

            print(tables)
            # Clear the table firstly.
            cursor.execute('''DELETE FROM Experiment WHERE 1=1''')

            # Now insert some data into it.
            cursor.execute(
                    '''INSERT INTO Experiment (id, name, assigned, completed, estimated_time, start, terminate) VALUES (%s, %s, %s, %s, %s, %s, %s)''',
                    [
                        2660792221924433694, 'e0', '2010-06-25', '2010-06-25', 0, '2010-06-25T12:15:30.747000Z', '2010-06-25T12:15:30.747000Z',
                        673743920250785767, 'e1', '2010-06-25', '2010-06-26', 253000, '2010-06-26T12:15:30.747000Z', '2010-06-26T12:15:31.000000Z',
                    ])

            cursor.execute('''SELECT
                                *
                              FROM
                                Experiment 
                              WHERE
                                assigned <
                                ((TIMESTAMP_SUB(completed, INTERVAL %s MICROSECOND)))
                              ORDER BY
                                name
                              ASC''', (345600000000,))
            listing = cursor.fetchall()
            for item in listing:
                print(item)

if __name__ == '__main__':
    main()

Results

...
  File "/Users/emmanuelodeke/Library/Python/3.7/lib/python/site-packages/spanner/dbapi/cursor.py", line 112, in execute
    raise ProgrammingError(e.details if hasattr(e, 'details') else e)
spanner.dbapi.exceptions.ProgrammingError: 400 No matching signature for function TIMESTAMP_SUB for argument types: DATE, INTERVAL INT64 DATE_TIME_PART. Supported signature: TIMESTAMP_SUB(TIMESTAMP, INTERVAL INT64 DATE_TIME_PART) [at 7:35]\n                                ((TIMESTAMP_SUB(completed, INTERVAL @a0 MICRO...\n 

Full investigation:

This is what the full statement looks like

SELECT
    expressions_ExPeRiMeNt.id, expressions_ExPeRiMeNt.name,
    expressions_ExPeRiMeNt.assigned, expressions_ExPeRiMeNt.completed, 
    expressions_ExPeRiMeNt.estimated_time, expressions_ExPeRiMeNt.start, 
    expressions_ExPeRiMeNt.`end`
FROM
    expressions_ExPeRiMeNt
WHERE
    expressions_ExPeRiMeNt.assigned < 
    ((TIMESTAMP_SUB(expressions_ExPeRiMeNt.completed, INTERVAL %s MICROSECOND)))
ORDER BY
    expressions_ExPeRiMeNt.name
ASC
Args: (345600000000,)

and failure now:

django.db.utils.ProgrammingError: 400 No matching signature for function
TIMESTAMP_SUB for argument types: DATE, INTERVAL INT64 DATE_TIME_PART. Supported 
signature: TIMESTAMP_SUB(TIMESTAMP, INTERVAL INT64 DATE_TIME_PART) [at 1:299]\n
...WHERE expressions_ExPeRiMeNt.assigned < ((TIMESTAMP_SUB(expressions_ExPeRi...\n  

with relevant Django code at
https://github.com/django/django/blob/828e3b1335e2614d338a630fd5b5f88d38a6b5d2/tests/expressions/tests.py#L1561-L1565
aka

    def test_date_minus_duration(self):
        more_than_4_days = Experiment.objects.filter(
            assigned__lt=F('completed') - Value(datetime.timedelta(days=4), output_field=DurationField())
        )
        self.assertQuerysetEqual(more_than_4_days, ['e3', 'e4', 'e5'], lambda e: e.name)

and the respective model is

class Experiment(models.Model):
    name = models.CharField(max_length=24)
    assigned = models.DateField()
    completed = models.DateField()
    estimated_time = models.DurationField()
    start = models.DateTimeField()
    end = models.DateTimeField()

which translates into the following DDL

CREATE TABLE Experiment (
    name STRING(24)
    id STRING(32) NOT NULL,
    assigned DATE,
    completed DATE,
    estimated_time INT64,
    start TIMESTAMP,
    end TIMESTAMP
) PRIMARY KEY(id)

and for some population SQL

SQL:  INSERT INTO expressions_ExPeRiMeNt (id, name, assigned, completed, estimated_time, start, `end`) VALUES (%s, %s, %s, %s, %s, %s, %s)
Args: (2660792221924433694, 'e0', '2010-06-25', '2010-06-25', 0, '2010-06-25T12:15:30.747000Z', '2010-06-25T12:15:30.747000Z')

SQL:  INSERT INTO expressions_ExPeRiMeNt (id, name, assigned, completed, estimated_time, start, `end`) VALUES (%s, %s, %s, %s, %s, %s, %s)
Args: (673743920250785767, 'e1', '2010-06-25', '2010-06-26', 253000, '2010-06-26T12:15:30.747000Z', '2010-06-26T12:15:31.000000Z')

SQL:  INSERT INTO expressions_ExPeRiMeNt (id, name, assigned, completed, estimated_time, start, `end`) VALUES (%s, %s, %s, %s, %s, %s, %s)
Args: (4474564260460410667, 'e2', '2010-06-22', '2010-06-25', 3600000000, '2010-06-25T12:15:30.747000Z', '2010-06-25T12:16:14.747000Z')

SQL:  INSERT INTO expressions_ExPeRiMeNt (id, name, assigned, completed, estimated_time, start, `end`) VALUES (%s, %s, %s, %s, %s, %s, %s)
Args: (2820814987796123967, 'e3', '2010-06-25', '2010-06-30', 76080000000, '2010-06-29T12:15:30.747000Z', '2010-06-30T09:23:30.747000Z')

SQL:  INSERT INTO expressions_ExPeRiMeNt (id, name, assigned, completed, estimated_time, start, `end`) VALUES (%s, %s, %s, %s, %s, %s, %s)
Args: (3527083678376937815, 'e4', '2010-06-15', '2010-07-05', 777600000000, '2010-06-25T12:15:30.747000Z', '2010-07-05T12:15:30.747000Z')

SQL:  INSERT INTO expressions_ExPeRiMeNt (id, name, assigned, completed, estimated_time, start, `end`) VALUES (%s, %s, %s, %s, %s, %s, %s)
Args: (2875353117097818790, 'e5', '2010-06-25', '2010-10-23', 7776000000000, '2010-07-25T12:15:30.747000Z', '2010-10-23T12:15:30.747000Z')

[odeke-em]

Seems like only strings are passed into spanner.django.operations.DatabaseOperations.combine_duration_expression
https://github.com/orijtech/django-spanner/blob/c6cfd6ff4ad43f28a69dea2c6b7bf8ed6e0608f7/spanner/django/operations.py#L207-L213

so I can't switch or predict the types of operations thus I shall refer this to you @timgraham, otherwise I'd have sent a PR now that the functions to be used are straightforward.

[timgraham]

When I filed this issue, I didn't have a solution in mind. I'm not sure it's solvable but perhaps Spanner engineers can comment if the limitation has come up before.

[timgraham]

This VERSION (adding CAST ... AS TIMESTAMP) doesn't really make things better:

def combine_duration_expression(self, connector, sub_expressions):
        if connector == '+':
            return 'TIMESTAMP_ADD(CAST(%s AS TIMESTAMP), %s)' % tuple(sub_expressions)
        elif connector == '-':
            return 'TIMESTAMP_SUB(CAST(%s AS TIMESTAMP), %s)' % tuple(sub_expressions)
        else:
            raise DatabaseError('Invalid connector for timedelta: %s.' % connector)

Usually if the first argument is a date, then a date is expected to be returned, not a timestamp. Example test failure:

======================================================================
ERROR: test_date_comparison (expressions.tests.FTimeDeltaTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/api_core/grpc_helpers.py", line 79, in next
    return six.next(self._wrapped)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/grpc/_channel.py", line 392, in __next__
    return self._next()
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/grpc/_channel.py", line 561, in _next
    raise self
grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with:
	status = StatusCode.INVALID_ARGUMENT
	details = "No matching signature for operator < for argument types: DATE, TIMESTAMP. Supported signature: ANY < ANY [at 1:263]\n...end` FROM expressions_ExPeRiMeNt WHERE expressions_ExPeRiMeNt.completed < ...\n                                          ^"
	debug_error_string = "{"created":"@1585093360.431840248","description":"Error received from peer ipv4:172.217.11.42:443","file":"src/core/lib/surface/call.cc","file_line":1055,"grpc_message":"No matching signature for operator < for argument types: DATE, TIMESTAMP. Supported signature: ANY < ANY [at 1:263]\n...end` FROM expressions_ExPeRiMeNt WHERE expressions_ExPeRiMeNt.completed < ...\n                                          ^","grpc_status":3}"
>

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/tim/code/spanner-django/spanner/dbapi/autocommit_on_cursor.py", line 55, in execute
    self.__handle_DQL(sql, args or None)
  File "/home/tim/code/spanner-django/spanner/dbapi/autocommit_on_cursor.py", line 153, in __handle_DQL
    self._itr = PeekIterator(self._res)
  File "/home/tim/code/spanner-django/spanner/dbapi/utils.py", line 30, in __init__
    head = next(itr_src)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/streamed.py", line 143, in __iter__
    self._consume_next()
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/streamed.py", line 116, in _consume_next
    response = six.next(self._response_iterator)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/snapshot.py", line 45, in _restart_on_unavailable
    for item in iterator:
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/api_core/grpc_helpers.py", line 81, in next
    six.raise_from(exceptions.from_grpc_error(exc), exc)
  File "<string>", line 3, in raise_from
google.api_core.exceptions.InvalidArgument: 400 No matching signature for operator < for argument types: DATE, TIMESTAMP. Supported signature: ANY < ANY [at 1:263]\n...end` FROM expressions_ExPeRiMeNt WHERE expressions_ExPeRiMeNt.completed < ...\n                                          ^

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/tim/code/django/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/home/tim/code/spanner-django/spanner/dbapi/autocommit_on_cursor.py", line 63, in execute
    raise ProgrammingError(e.details if hasattr(e, 'details') else e)
spanner.dbapi.exceptions.ProgrammingError: 400 No matching signature for operator < for argument types: DATE, TIMESTAMP. Supported signature: ANY < ANY [at 1:263]\n...end` FROM expressions_ExPeRiMeNt WHERE expressions_ExPeRiMeNt.completed < ...\n                                          ^

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/tim/code/django/tests/expressions/tests.py", line 1193, in test_date_comparison
    test_set = [e.name for e in Experiment.objects.filter(completed__lt=F('assigned') + days)]
  File "/home/tim/code/django/django/db/models/query.py", line 274, in __iter__
    self._fetch_all()
  File "/home/tim/code/django/django/db/models/query.py", line 1242, in _fetch_all
    self._result_cache = list(self._iterable_class(self))
  File "/home/tim/code/django/django/db/models/query.py", line 55, in __iter__
    results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size)
  File "/home/tim/code/django/django/db/models/sql/compiler.py", line 1140, in execute_sql
    cursor.execute(sql, params)
  File "/home/tim/code/django/django/db/backends/utils.py", line 67, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/home/tim/code/django/django/db/backends/utils.py", line 76, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/home/tim/code/django/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/home/tim/code/django/django/db/utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/home/tim/code/django/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/home/tim/code/spanner-django/spanner/dbapi/autocommit_on_cursor.py", line 63, in execute
    raise ProgrammingError(e.details if hasattr(e, 'details') else e)
django.db.utils.ProgrammingError: 400 No matching signature for operator < for argument types: DATE, TIMESTAMP. Supported signature: ANY < ANY [at 1:263]\n...end` FROM expressions_ExPeRiMeNt WHERE expressions_ExPeRiMeNt.completed < ...\n                     

There's also the possibility that the first argument is an interval like this:

======================================================================
ERROR: test_delta_add (expressions.tests.FTimeDeltaTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/api_core/grpc_helpers.py", line 79, in next
    return six.next(self._wrapped)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/grpc/_channel.py", line 392, in __next__
    return self._next()
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/grpc/_channel.py", line 561, in _next
    raise self
grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with:
	status = StatusCode.INVALID_ARGUMENT
	details = "Syntax error: Unexpected keyword INTERVAL [at 1:315]\n...expressions_ExPeRiMeNt.`end` < ((TIMESTAMP_ADD(CAST(INTERVAL 0 MICROSECOND...\n                                                       ^"
	debug_error_string = "{"created":"@1585093426.459524364","description":"Error received from peer ipv4:172.217.10.234:443","file":"src/core/lib/surface/call.cc","file_line":1055,"grpc_message":"Syntax error: Unexpected keyword INTERVAL [at 1:315]\n...expressions_ExPeRiMeNt.`end` < ((TIMESTAMP_ADD(CAST(INTERVAL 0 MICROSECOND...\n                                                       ^","grpc_status":3}"
>

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/tim/code/spanner-django/spanner/dbapi/autocommit_on_cursor.py", line 55, in execute
    self.__handle_DQL(sql, args or None)
  File "/home/tim/code/spanner-django/spanner/dbapi/autocommit_on_cursor.py", line 153, in __handle_DQL
    self._itr = PeekIterator(self._res)
  File "/home/tim/code/spanner-django/spanner/dbapi/utils.py", line 30, in __init__
    head = next(itr_src)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/streamed.py", line 143, in __iter__
    self._consume_next()
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/streamed.py", line 116, in _consume_next
    response = six.next(self._response_iterator)
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/cloud/spanner_v1/snapshot.py", line 45, in _restart_on_unavailable
    for item in iterator:
  File "/home/tim/.virtualenvs/django37/lib/python3.7/site-packages/google/api_core/grpc_helpers.py", line 81, in next
    six.raise_from(exceptions.from_grpc_error(exc), exc)
  File "<string>", line 3, in raise_from
google.api_core.exceptions.InvalidArgument: 400 Syntax error: Unexpected keyword INTERVAL [at 1:315]\n...expressions_ExPeRiMeNt.`end` < ((TIMESTAMP_ADD(CAST(INTERVAL 0 MICROSECOND...\n                                                       ^

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/tim/code/django/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/home/tim/code/spanner-django/spanner/dbapi/autocommit_on_cursor.py", line 63, in execute
    raise ProgrammingError(e.details if hasattr(e, 'details') else e)
spanner.dbapi.exceptions.ProgrammingError: 400 Syntax error: Unexpected keyword INTERVAL [at 1:315]\n...expressions_ExPeRiMeNt.`end` < ((TIMESTAMP_ADD(CAST(INTERVAL 0 MICROSECOND...\n                                                       ^

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/tim/code/django/tests/expressions/tests.py", line 1169, in test_delta_add
    test_set = [e.name for e in Experiment.objects.filter(end__lt=delta + F('start'))]
  File "/home/tim/code/django/django/db/models/query.py", line 274, in __iter__
    self._fetch_all()
  File "/home/tim/code/django/django/db/models/query.py", line 1242, in _fetch_all
    self._result_cache = list(self._iterable_class(self))
  File "/home/tim/code/django/django/db/models/query.py", line 55, in __iter__
    results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size)
  File "/home/tim/code/django/django/db/models/sql/compiler.py", line 1140, in execute_sql
    cursor.execute(sql, params)
  File "/home/tim/code/django/django/db/backends/utils.py", line 67, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/home/tim/code/django/django/db/backends/utils.py", line 76, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/home/tim/code/django/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/home/tim/code/django/django/db/utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/home/tim/code/django/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/home/tim/code/spanner-django/spanner/dbapi/autocommit_on_cursor.py", line 63, in execute
    raise ProgrammingError(e.details if hasattr(e, 'details') else e)
django.db.utils.ProgrammingError: 400 Syntax error: Unexpected keyword INTERVAL [at 1:315]\n...expressions_ExPeRiMeNt.`end` < ((TIMESTAMP_ADD(CAST(INTERVAL 0 MICROSECOND...\n 

[timgraham]

Until (if feasible) Spanner provides a way of adding date or datetime with interval that doesn't require choosing between TIMESTAMP_ADD and DATE_ADD, I've proposed to document this limitation in #446.

[asthamohta]

Currently this is a documented know issue as per this: #446 that we don't plan on working, hence closing this issue