[Python] GridDB_Python - unable to get row count on griddb table

I'm trying to write and read large data on griddb using python, and I'll try it first for small data. But when I wanted to calculate the row count, I failed to get it, even though I had tried several variations. Here's my code snippet:

import griddb_python

def create_griddb_connection():
factory = griddb_python.StoreFactory.get_instance()
return factory.get_store(host='127.0.0.1', port=10001, cluster_name='myCluster', username='admin', password='admin')

def get_container(store, container_name):
desc = griddb_python.ContainerInfo(
name=container_name,
column_info_list=[
["id", griddb_python.Type.INTEGER],
["data", griddb_python.Type.STRING]
],
type=griddb_python.ContainerType.COLLECTION
)
container = store.put_container(desc)
return container

def write_data(container, num_records=1000):
for i in range(num_records):
data = [i, f"data_{i}"]
container.put(data)

print(f"Write {num_records} data completed")

def read_data(container, container_name):
sqlSelect = f"SELECT * FROM {container_name} limit 1"
query = container.query(sqlSelect)
result = query.fetch()
if result.has_next():
row = result.next()
print (f"First row data: [{row[0]}-{row[1]}]")
else:
print("No rows")

sqlSelect = f"SELECT COUNT(*) FROM {container_name}"
query = container.query(sqlSelect)
result = query.fetch()
if result.has_next():
row = result.next()
#print (f"Row count:{row[0]}")
#print (f"Row count:{row.getvalue(0)}")
#print (f"Row count:{row.get(0)}")
else:
print("No rows")

result.close()
query.close()

def main():
store = create_griddb_connection()
container_name = "test_container"

container = get_container(store, container_name)
write_data(container, num_records=1000)
read_data(container, container_name)

container.close()
store.close()

if __name__ == "__main__":
main()


When I executed it without "SELECT COUNT", it is successful with the output:

Write 1000 data completed
First row data: [0-data_0]


But when I uncommented the print command on "SELECT COUNT", it produces error with the following error message:

print (f"Row count:{row[0]}") produces error: 'AggregationResult' object is not subscriptable

print (f"Row count:{row.getvalue(0)}") produces error: 'AggregationResult' object has no attribute 'getvalue'

print (f"Row count:{row.get(0)}") produces error: griddb_python.GSException

When I detailed the error message, with this code snippet:

try:
row = result.next()
print (f"Row count:{row.get(0)}")
except Exception as e:
for i in range(e.get_error_stack_size()):
print("[", i, "]")
print(e.get_error_code(i))
print(e.get_message(i))


It produces an error message: [140037:CC_NO_SUCH_ELEMENT]

Has anyone experienced something similar?

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