I keep getting error messages while querying with ODBC connector to Impala (using pyodbc package for python):
pyodbc.OperationalError: ('08S01', '[08S01] [Cloudera][ImpalaODBC] (120) Error while retrieving data from in Impala: [08S01] : ImpalaThriftAPICallFailed (120) (SQLFetch)')
I have a smaller table (table1) and a bigger table (table2).
With the smaller table I tried with one and 10 processses and everything worked fine.
When I started 50 parallel python process, each having separate connection to Impala with pyodbc, after a few seconds I got the error message above (when calling cursor.fetchmany(1000) function).
With the bigger table, I got the error even with 1 process.
Windows 10 + official Impala ODBC driver
The python program creates a process, connects with pyodbc to Impala and executes queries for 3 minutes. Then closes the cursor and the connection.
1 master + 4 tablet server
Impala 3.1.0, Kudu 1.8.0 (CDH 6.1 with default parameters)
Data stored in Kudu table1: ~0.7 10^9 row (with 7 columns)
Data stored in Kudu table2: ~18 10^9 row (with 7 columns)
I also got this error while using CentOS 7 + official Impala ODBC driver
While using LIMIT 100 on the queries, still got this error, but previously it happened earlier.
While using JDBC connector, everything worked fine for 1, 10 and 50 processes.