What Is an Active Statement?

An active statement is a SQL command that has already been executed by the database server but:

• Its result set is still open, and
• It has not been fully processed, canceled, or closed.

This typically occurs with queries (SELECT statements) rather than INSERT, UPDATE, or DELETE, which usually don’t leave open result sets.

 Lifecycle of a SQL Statement

1. Prepare/Parse (optional) – SQL is parsed and compiled.
2. Execute – The database runs the statement and starts returning results.
3. Fetch/Process – The client retrieves rows from the result set.
4. Close/Cancel – The result set is either fully read or explicitly closed.

 Why Are Active Statements Important?

1. Resource Usage
   • Open cursors consume memory on the database server and sometimes on the client.
2. Concurrency Limits
   • Many databases limit the number of active statements per session/connection (e.g., one active statement per connection in some embedded DBs like SQLite or old JDBC drivers).
3. Blocking and Locking
   • Active statements may hold locks (e.g., SELECT...FOR UPDATE) that block other queries.
4. Performance
   • Forgetting to close a result set or cursor can lead to resource leaks and degrade performance.