| Bug #38747 | java.sql.SQLException: Connection is read-only. Queries leading to data modifica | ||
|---|---|---|---|
| Submitted: | 12 Aug 2008 11:01 | Modified: | 10 Oct 2008 8:42 |
| Reporter: | Pavel Sher | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | Connector / J | Severity: | S2 (Serious) |
| Version: | 5.1.6 | OS: | Any |
| Assigned to: | CPU Architecture: | Any | |
[12 Aug 2008 11:06]
Tonci Grgin
Hi Pavel and thanks for your report. I do not share your enthusiasm about usability of stack trace so please attach small but complete test case proving your point.
[12 Aug 2008 13:53]
Pavel Sher
The following code reproduces bug in my case:
connection.setReadOnly(true);
PreparedStatement st = connection.prepareStatement("SELECT 1", ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
st.setFetchSize(Integer.MIN_VALUE);
ResultSet rs = st.executeQuery();
rs.close();
According to MySQL documentation combination of options ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY and Integer.MIN_VALUE turns on dynamic result set which I use in my code.
[13 Aug 2008 9:03]
Tonci Grgin
Test case, using SVN repository sources and our test fw
Attachment: TestBug38747.java (text/x-java), 1.97 KiB.
[13 Aug 2008 9:06]
Tonci Grgin
Hi Pavel. Verified as described with test case attached. Besides what's visible in test case, my connection string contains: &autoReconnect=false&connectTimeout=5000&socketTimeout=30000
[21 Aug 2008 18:39]
Kevin Fries
We have the same problem with the 5.1.6 driver. 5.0.7 doesn't have the problem. Appears that setting netTimeoutForStreamingResults=0 is a usable workaround The issue (looking at the source) seems to be that the driver doesn't let itself execute stmt.executeUpdate("SET net_write_timeout=" + oldValue);
Other calls in the driver which issue "SET " statements seem to use the call : executeSimpleNonQuery which does not restrict readonly connections from issuing SET commands.
[29 Sep 2008 16:14]
Mark Matthews
Fixed for 5.1.7.
[10 Oct 2008 8:42]
Tony Bedford
An entry was added to the 5.1.7 changelog:
Connector/J threw the following exception when using a read-only connection:
java.sql.SQLException: Connection is read-only. Queries leading to data
modification are not allowed.
Description: I am using MySQL Connector/J 5.1.6, and I've got the following exception in my application: java.sql.SQLException: Connection is read-only. Queries leading to data modification are not allowed. at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1516) at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1485) at com.mysql.jdbc.RowDataDynamic.close(RowDataDynamic.java:195) at com.mysql.jdbc.ResultSetImpl.realClose(ResultSetImpl.java:7473) at com.mysql.jdbc.ResultSetImpl.close(ResultSetImpl.java:881) After looking at code in MySQL driver I see that driver tries to execute statement: stmt.executeUpdate("SET net_write_timeout=" + oldValue); But if transaction is read only (as in my case), this code will throw an exception. I consider this is a bug in the MySQL driver since I do not expect any update statements when I am closing result set. How to repeat: I think stacktrace contains enough information to reproduce this bug.