MySQL Bugs: #3883: Mysql Connector/J (3.1.1-alpha) Compression doesn't work

Bug #3883	Mysql Connector/J (3.1.1-alpha) Compression doesn't work - connection resets
Submitted:	25 May 2004 22:26	Modified:	25 May 2004 22:52
Reporter:	Mudit Wahal	Email Updates:
Status:	Duplicate	Impact on me:	None
Category:	Connector / J	Severity:	S1 (Critical)
Version:	3.1-nightly-20040524	OS:	Windows (Windows XP)
Assigned to:		CPU Architecture:	Any

Description:

The compression feature of the 3.1.1-alpha and also the latest nightly build (May 24th tried) doesn't work when you to select from a non existing table and
then issue second select command. The second command hangs the system for a while and then gives Unknown command exception. The log from the server side shows that the second select request was incomplete .. only "se^N" was
send.

How to repeat:

With useCompression=true, try to select from a non existing table and
then try to issue another select command. Its very easily reproducible.
Will attach the program which has details about how to reproduce it.

Test Case to create compression hang bug

Attachment: TestQuery.java (text/x-java), 5.13 KiB.

Output of the program, without and with compression enabled/disabled.

Thanks

Mudit

--------- run with compression set to false --------------
C:\Temp>mk
URL = jdbc:mysql://xx.xx.xx.xx:3306/?autoReconnect=true&useCompression
=false
Trying to connect ... connected!
statement = SELECT * FROM test_sql_compress.absent
SQLException: Base table or view not found message from server: "Table 'test_sql
_compress.absent' doesn't exist"
statement = SELECT * FROM test_sql_compress.present
=======  Result query = SELECT * FROM test_sql_compress.present =====
MySQL Connector
Testing UseCompress
======End of query =======

----------- run with compression set to true -------------
C:\Temp>mk true
URL = jdbc:mysql://xx.xx.xx.xx:3306/?autoReconnect=true&useCompression
=true
Trying to connect ... connected!
statement = SELECT * FROM test_sql_compress.absent
SQLException: Base table or view not found message from server: "Table 'test_sql
_compress.absent' doesn't exist"
statement = SELECT * FROM test_sql_compress.present
SQLException: Server connection failure during transaction. Due to underlying ex
ception: 'java.sql.SQLException: Communication link failure message from server:
 "Unknown command"'.

** BEGIN NESTED EXCEPTION **

java.sql.SQLException
MESSAGE: Communication link failure message from server: "Unknown command"

STACKTRACE:

java.sql.SQLException: Communication link failure message from server: "Unknown
command"
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2441)
        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1396)
        at com.mysql.jdbc.Connection.ping(Connection.java:3207)
        at com.mysql.jdbc.Connection.createNewIO(Connection.java:1799)
        at com.mysql.jdbc.Connection.execSQL(Connection.java:2248)
        at com.mysql.jdbc.Connection.execSQL(Connection.java:2199)
        at com.mysql.jdbc.Statement.executeQuery(Statement.java:1182)
        at TestQuery.do_select(TestQuery.java:87)
        at TestQuery.send_queries(TestQuery.java:153)
        at TestQuery.<init>(TestQuery.java:131)
        at TestQuery.main(TestQuery.java:103)

** END NESTED EXCEPTION **

Attempted reconnect 3 times. Giving up.
C:\Temp>

----------- mk.bat file ----------
@echo off
javac -classpath c:\mystocks\mysql-connector-java-3.1-nightly-20040524-bin.jar TestQuery.java
java -classpath c:\mystocks\mysql-connector-java-3.1-nightly-20040524-bin.jar;. TestQuery %1

-----------------------------------

Changed version to correct nightly build used in the test case.

This is a duplicate of 3826