[NIFI-3425] Cache prepared statements in PutCassandraQL

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.8.0
• Assignee: Matt Burgess
• Reporter: Matt Burgess
• Created: 01/Feb/17 13:47
• Updated: 14/Sep/18 15:38
• Resolved: 14/Sep/18 15:38

Description

Currently PutCassandraQL supports prepared statements (using ? parameters much like JDBC SQL statements) via flow file attributes specifying the type and value of the parameters.

However, the prepared statement is created (and thus possibly re-created) for each flow file, which neuters its effectiveness over literal CQL statements. The driver warns of this:

2017-01-31 14:30:54,287 WARN [cluster1-worker-1] com.datastax.driver.core.Cluster Re-preparing already prepared query insert into test_table (id, timestamp, id1, timestamp1, id
2, timestamp2, id3, timestamp3, id4, timestamp4, id5, timestamp5, id6, timestamp6) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);. Please note that preparing the same query
more than once is generally an anti-pattern and will likely affect performance. Consider preparing the statement only once.

Prepared statements should be cached and reused where possible.

Issue Links

• links to: GitHub Pull Request #2986