Update query for cassandra using variable in python -


i trying run update query variables. using casandra-driver guided in datastax website.i using following script connect cluster , update values in table ct_table. 

from cassandra.cluster import cluster cluster = cluster() session = cluster.connect('ct_keyspace') a=90 session.execute("update ct_table set value=%d attribute='ct'",(int(a))) result = session.execute("select * ct_table attribute='ct'")[0] print result.attribute, result.value

i getting following error

traceback (most recent call last):   file "connection.py", line 7, in <module>     session.execute("update ct_table set value=%d attribute='ct'",(a))   file "/usr/local/lib/python2.7/dist-packages/cassandra/cluster.py", line 1998, in execute     return self.execute_async(query, parameters, trace, custom_payload, timeout, execution_profile, paging_state).result()   file "/usr/local/lib/python2.7/dist-packages/cassandra/cluster.py", line 2035, in execute_async     future = self._create_response_future(query, parameters, trace, custom_payload, timeout, execution_profile, paging_state)   file "/usr/local/lib/python2.7/dist-packages/cassandra/cluster.py", line 2095, in _create_response_future     query_string = bind_params(query_string, parameters, self.encoder)   file "/usr/local/lib/python2.7/dist-packages/cassandra/query.py", line 823, in bind_params     return query % tuple(encoder.cql_encode_all_types(v) v in params) typeerror: 'int' object not iterable

my table looks this:

cqlsh:ct_keyspace> describe ct_table  create table ct_keyspace.ct_table (     attribute text primary key,     value int ) bloom_filter_fp_chance = 0.01     , caching = '{"keys":"all", "rows_per_partition":"none"}'     , comment = ''     , compaction = {'class': 'org.apache.cassandra.db.compaction.sizetieredcompactionstrategy'}     , compression = {'sstable_compression': 'org.apache.cassandra.io.compress.lz4compressor'}     , dclocal_read_repair_chance = 0.1     , default_time_to_live = 0     , gc_grace_seconds = 864000     , max_index_interval = 2048     , memtable_flush_period_in_ms = 0     , min_index_interval = 128     , read_repair_chance = 0.0     , speculative_retry = '99.0percentile';

value defined in table int . suspect formatting string update query incorrectly.

session.execute("update ct_table set value=%d attribute='ct'",(int(a)))

should be

session.execute("update ct_table set value=%s attribute='ct'", (a,))

we're specifying bind marker %s , passing tuple parameter list. without trailing comma, it's value.

see also: https://datastax.github.io/python-driver/getting_started.html#passing-parameters-to-cql-queries

note should use %s types of arguments, not strings


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