Message-ID: <gh-pgjdbc-pgjdbc-3462-c2552103859@github.com>
From: "butopcu (@butopcu)" <noreply+butopcu@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Wed, 18 Dec 2024 19:25:15 +0000
Subject: Re: [pgjdbc/pgjdbc] issue #3462: Next Method of PgResultSet Throws NullPointerException Instead of SQLException
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@vlsi 
Actually, each thread uses new `ResultSet` and `Statement` objects as these are local variables.  
Our Database Team has thoroughly investigated the code and PostgreSQL logs but couldn't determine why the `ResultSet` occasionally and rarely switches to a closed state.

The same SQL queries are being executed with different parameters across multiple threads:

**Thread 1**:  
- Integers: `WHERE IN (1..500)` (Main SQL Query to TableA)  
  - The `ResultSet` remains open (`TYPE_SCROLL_INSENSITIVE`).  
- Process all data in a loop:  
  - `WHERE = ID` (Subquery to TableB for each entry returned from TableA). (New ResultSet, Connection and Statement)

**Thread 2**:  
- Integers: `WHERE IN (501..1000)` (Main SQL Query to TableA).  
- Process all data in a loop:  
  - `WHERE = ID` (Subquery to TableB for each entry returned from TableA).


The only static object is the SQL query string, such as:

`private static final String QUERY_BY_ID= "SELECT name, adress FROM TABLEB WHERE ID=?";`