[CALCITE-1052] Phoenix queryserver sends result set in response to the wrong request when there are concurrent requests

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Cannot Reproduce
• Fix Version/s: 1.7.0
• Component/s: avatica
• Labels: phoenix queryserver
• Assignee: Josh Elser
• Reporter: Kevin Liew
• Created: 08/Jan/16 20:50
• Updated: 22/Mar/16 01:19
• Resolved: 17/Feb/16 23:38

Description

Create two tables

DROP TABLE IF EXISTS SEN.VARCHAR_TABLE;
CREATE TABLE IF NOT EXISTS SEN.VARCHAR_TABLE(
	KeyColumn VARCHAR(255) PRIMARY KEY,
	Column1 VARCHAR(510));

UPSERT INTO SEN.VARCHAR_TABLE VALUES ('One','1');

DROP TABLE IF EXISTS SEN.INTEGER_TABLE;
CREATE TABLE IF NOT EXISTS SEN.INTEGER_TABLE(
	KeyColumn VARCHAR(255) PRIMARY KEY,
	Column1 INTEGER);

UPSERT INTO SEN.INTEGER_TABLE VALUES ('Two',2);

Running these two programs results in several crashes.

1. select a varchar by parameterized statement resulting in
SELECT Column1 FROM SEN.VARCHAR_TABLE WHERE KeyColumn = 'One'

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.PreparedStatement;
import java.sql.Statement;

public class Hello_World {
	public static void main(String[] args) throws SQLException {
		try {
            Class.forName("org.apache.phoenix.queryserver.client.Driver");
        } catch (ClassNotFoundException e) {
            System.out.println("Where is your PhoenixDriver");
            e.printStackTrace();
            return;
        }

		Connection conn = DriverManager.getConnection("jdbc:phoenix:thin:url=http://192.168.222.52:8765");
		conn.setAutoCommit(true);

		String sqlStmt = "SELECT Column1 FROM SEN.VARCHAR_TABLE WHERE KeyColumn = ?";
		System.out.println("SQL Statement:\n\t" + sqlStmt);
		
		while(true)
		{
			ResultSet rset = null;
	
			//Statement stmt = conn.createStatement();
			PreparedStatement stmt = conn.prepareStatement(sqlStmt);
			stmt.setString(1, "One");
			ResultSet rs = stmt.executeQuery();
      
			while (rs.next()) {
		    	String column1 = rs.getString("column1");
		    	if (!column1.equals("1"))
		    	{
		    		System.out.println(column1);
		    	}
			}
		}
		
        //conn.close();
	}
	
}

2. select an integer by parameterized statement resulting in
SELECT Column1 FROM SEN.INTEGER_TABLE WHERE KeyColumn = 'Two'

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.PreparedStatement;
import java.sql.Statement;



public class Hello_World {
	public static void main(String[] args) throws SQLException {
		try {
            Class.forName("org.apache.phoenix.queryserver.client.Driver");
        } catch (ClassNotFoundException e) {
            System.out.println("Where is your PhoenixDriver");
            e.printStackTrace();
            return;
        }

		Connection conn = DriverManager.getConnection("jdbc:phoenix:thin:url=http://192.168.222.52:8765");
		conn.setAutoCommit(true);
		
		String sqlStmt = "SELECT Column1 FROM SEN.INTEGER_TABLE WHERE KeyColumn = ?";
		System.out.println("SQL Statement:\n\t" + sqlStmt);
		
		while(true)
		{
			ResultSet rset = null;
	
			//Statement stmt = conn.createStatement();
			PreparedStatement stmt = conn.prepareStatement(sqlStmt);
			stmt.setString(1, "Two");
			ResultSet rs = stmt.executeQuery();
      
			while (rs.next()) {
		    	int column1 = rs.getInt("column1");
		    	if (column1 != 2)
		    	{
		    		System.out.println(column1);
		    	}
			}
		}
		
        //conn.close();
	}
	
}

There are several crashes (might be preventable by adding a pause in the loops?), but the one relevant to this bug is:

SQL Statement:
	SELECT Column1 FROM SEN.INTEGER_TABLE WHERE KeyColumn = ?
Exception in thread "main" java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Number
	at org.apache.calcite.avatica.util.AbstractCursor$NumberAccessor.getNumber(AbstractCursor.java:661)
	at org.apache.calcite.avatica.util.AbstractCursor$BigNumberAccessor.getInt(AbstractCursor.java:602)
	at org.apache.calcite.avatica.AvaticaResultSet.getInt(AvaticaResultSet.java:314)
	at Hello_World.main(Hello_World.java:36)

where we get a string from SEN.VARCHAR_TABLE while we are querying from the SEN.INTEGER_TABLE.

The queryserver is sending the result set in response to a request made from another connection id. The statement id was not checked but there may have been a statement id collision