MySQL Forums - Connector/J, JDBC and Java

socketTimeout uses double the value? (4 replies)

Etienne Hardy — Mon, 23 Feb 2026 12:45:09 +0000

Hello,

I would like to confirm a behaviour we have been observing with the MySQL Java JDBC driver. We run the latest version available, 9.4.0. Whatever value we specify for socketTimeout, the timeout will instead be after twice that time. To validate, we have implemented a piece of code that does a "select sleep(10)" query. If we set socketTimeout=1000, the query times out after 2 seconds. If we set socketTimeout=2000, the query times out after 4 seconds. We have observed this behaviour consistently. The driver documentation makes no mention of that behaviour.

Thanks in advance

AbandonedConnectionCleanupThread's problem (1 reply)

weigang wu — Tue, 10 Feb 2026 20:18:59 +0000

When I analyzed heap memory using MAT, I found that 75% of the memory usage came from the connectionFinalizerPhantomRefs variable of the AbandonedConnectionCleanupThread. Why is this? The version I am using is
mysql
mysql-connector-java
8.0.32

The mysql connector (JAVA) time zone is faulty (2 replies)

songlin songlin — Tue, 18 Feb 2025 06:02:57 +0000

Env
JVM: UTC
JDBC:serverTimezone=Asia/Shanghai (CST)
Mysql: UTC

When I use mysql-Connector -java version 8.0.32, I find that when I first query a LocalDateTime data, which is stored in mysql timestamp, the query will do time zone conversion. However, when I use the time zone converted data to update the mysql data directly, I do not do the time zone converted, so the data I update is 8h smaller than the original data
I didn't have this problem when I used version 8.0.22 or later

Streaming query swallowing SQLException (1 reply)

Don Mitchell — Tue, 10 Feb 2026 19:31:12 +0000

Intermittent errors from our code are being swallowed someplace during streaming and causing the streaming to hang. I'm fairly certain it's occurring under `ResultSet.next`.

Is this a known problem? Is there a known workaround? We've tried catching and rethrowing the errors as other errors. They get caught but they still get muted.

Can someone point me to the streaming implementation of `ResultSet.next`? It's probably not actually that but whatever implements `this.rowData.next()`. I am curious whether com.mysql.cj.jdbc.result.ResultSetImpl#clearWarnings may be a causal agent.

The kotlin version of the iteration with annotation
``` kotlin
database.dirtyExecuteExpression(expression) { statement ->
logger.debug { "Running query: $statement" }
if (database.dialect is MySqlDialect) statement.fetchSize = Integer.MIN_VALUE
statement.queryTimeout = 0 // no timeout
try {
statement.executeQuery().use { rs ->
logger.debug { "Query: $rs" }
while (rs.next()) {
try {
action(rs)
} catch (e: SQLException) {
// catches the error but the throw hangs rather than exits the iteration
logger.error(e) { "Error during suspendable query $statement on ${statement.connection}" }
throw e
}
}
}
} catch (e: SQLException) {
// catches the eventual socket disconnect error
logger.error(e) { "Outer error during suspendable query $statement on ${statement.connection}" }
throw e
}
}
```

Inquiry About Patch Fix for CVE-2023-22102 in MySQL Connector Dependency (3 replies)

Tanuj Monga — Wed, 22 Jan 2025 12:29:07 +0000

Hi Team,

I am reaching out to inquire about the status of a patch fix for the vulnerability CVE-2023-22102 in the MySQL Connector dependency. This vulnerability has been flagged in our environment, and I am keen to understand if there is an updated version or a workaround available to mitigate the issue.

Could you please provide an update or guidance regarding the timeline for the patch release? Alternatively, if there's any official documentation or release notes addressing this vulnerability, I would greatly appreciate it if you could share the link.

Looking forward to your response.

Thank you!

Best regards,
Tanuj Monga

Specifying server name in certificate for TLS connection (4 replies)

Maciek M — Wed, 19 Feb 2025 08:50:53 +0000

Sometimes the hostname used to connect to a server differs from the subject name in the TLS certificate presented by this server (for valid reasons). Some JDBC drivers allow for that by providing a connection parameter where the expected name in certificate is specified (oracle.net.ssl_server_cert_dn for Oracle, hostNameInCertificate for MS SQL Server). I can't find a way to specify it for MySQL Connector/J. Is there any way to provide this server name, so that verification with sslMode=VERIFY_IDENTITY passes?

MySQL Connector/J 8.4.0 (5 replies)

Stack Philips — Tue, 21 Jan 2025 17:13:47 +0000

Hello everyone,
I am using mysql-connector-j 8.3.0 without any problems but when I tried to update the version to 8.4.0 or to 9.x I got a problem when start the application and trying to connect to the database.

Caused by: java.sql.SQLTransientConnectionException: HikariPool-default - Connection is not available, request timed out after 30004ms.

There are times when the connection does not cause any problems but it takes a long time to start. Do you know what could be the cause of this? With version 8.3.0 the connection starts very quickly.

MySQL Connector/J Observability with OpenTelemetry (no replies)

Edwin Desouza — Mon, 28 Oct 2024 22:19:03 +0000

https://blogs.oracle.com/mysql/post/mysql-connectorj-observability-with-opentelemetry

CVE-2024-7254 (1 reply)

Michael Bauschert — Mon, 28 Oct 2024 14:36:59 +0000

Hi

since 09-18 we have the CVE-2024-7254 which is part of the protobuf-java lib (a dependency of mysql-connector-j)

Is this CVE relevant for mysql-connector-j users?

Kind Rergards
Michael

Connector/J 9 supported databases (2 replies)

Volodymyr Magamedov — Mon, 23 Sep 2024 10:01:09 +0000

We are in the middle of migration from MySQL 5 to 8 and at the same time we're in the middle of Java virtual threads adoption. Connector/J 9 contain improvements for virtual threads and I wanted to ask if it's safe to upgrade Connector/J and continue using MySQL 5.7 for some of our databases which are not migrated yet?

I see that MySQL 5.7 support was dropped in 8.3.0 release, right after MySQL 5.7 EOL, so it looks like that MySQL 5.7 is not supported but this might not mean that it will not work.

So is it supposed to work or you already removed support for MySQL 5.7 from the code somewhere?

Spring JDBC template batchUpdate: multiple update statements (5 replies)

Hugo Ribeiro — Wed, 24 Jul 2024 09:32:19 +0000

Hey, hope you are doing great.

I have the following question/doubt: I am using spring jdbctemplate batchUpdate method passing in a prepared statement and a batch of params. What it then does is to grab that update statement, iterate every entry on the batch and create multiple update statemens separated by ";".

e.g.
update abc set col1 = ? where id = ?
batch -> [[val1, id1], [val2, id2], [val3, id3], [val4, id4]]

the following statement is created and executed:
update abc set col1=val1 where id=id1;update abc set col1=val2 where id=id2;update abc set col1=val3 where id=id3;update abc set col1=val4 where id=id4;

I am facing the following exception:
Caused by: java.sql.SQLException: syntax error at position 6 near 'pdate'
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:130) ~[mysql-connector-j-8.1.0.jar:8.1.0]

but if I grab the statement and try to run it e.g. on dbeaver it works.

Can you tell me what am I doing wrong here?

Thanks in advance.

Connector/J not found (1 reply)

Jorge Dalzotto — Mon, 08 Jul 2024 14:59:07 +0000

Hello,
Where are the download link for the Connector/J for MS Windows?
Because In the download page (https://dev.mysql.com/downloads/connector/j/)... They're not there.

Client-server compatibility 8.0-8.4 (2 replies)

Umur Poyraz — Tue, 21 May 2024 06:56:45 +0000

Hi all,
Can we use mysql connector 8.0 with mysql server 8.4(LTS)?
We want to upgrade to the latest LTS version but there are some clients which are still using Connector/J 8.0.
Not sure if they may face any issues.

Per field encoding (10 replies)

Tom Eugelink — Tue, 14 May 2024 05:56:56 +0000

Does the JDBC driver take table level encoding into account?

We have a decades old database which uses latin1 as its default character set, but individual tables have a deviating charset, utf8. Updating columns via setString works fine, using setCharachterStream does not. It fails on a

Caused by: java.sql.SQLException: Incorrect string value: '\xF2f een...' for column 'message' at row 1
at com.mysql@8.2.0//com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:130)
at com.mysql@8.2.0//com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
at com.mysql@8.2.0//com.mysql.cj.jdbc.ServerPreparedStatement.serverExecute(ServerPreparedStatement.java:555)
at com.mysql@8.2.0//com.mysql.cj.jdbc.ServerPreparedStatement.executeInternal(ServerPreparedStatement.java:339)
at com.mysql@8.2.0//com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdateInternal(ClientPreparedStatement.java:1054)
at com.mysql@8.2.0//com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdateInternal(ClientPreparedStatement.java:1003)
at com.mysql@8.2.0//com.mysql.cj.jdbc.ClientPreparedStatement.executeLargeUpdate(ClientPreparedStatement.java:1312)
at com.mysql@8.2.0//com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdate(ClientPreparedStatement.java:988)
at org.jboss.ironjacamar.jdbcadapters@1.5.3.Final//org.jboss.jca.adapters.jdbc.WrappedPreparedStatement.executeUpdate(WrappedPreparedStatement.java:537)
at deployment.ioserver.ear//io.ebeaninternal.server.bind.DataBind.executeUpdate(DataBind.java:102) [ebean-core-14.0.2-javax.jar:14.0.2-javax]
at deployment.ioserver.ear//io.ebeaninternal.server.persist.dml.InsertHandler.execute(InsertHandler.java:105) [ebean-core-14.0.2-javax.jar:14.0.2-javax]
at deployment.ioserver.ear//io.ebeaninternal.server.persist.dml.DmlHandler.executeNoBatch(DmlHandler.java:88) [ebean-core-14.0.2-javax.jar:14.0.2-javax]
at deployment.ioserver.ear//io.ebeaninternal.server.persist.dml.DmlBeanPersister.execute(DmlBeanPersister.java:69) [ebean-core-14.0.2-javax.jar:14.0.2-javax]
... 132 more

According to the JDBC documentation setCharacterStream is responsible for using the correct encoding, so I cannot fault the ORM library for not doing a conversion.

From what I gather examining the sources of mysql-connector-j, it only looks at the session for encoding information, not at table level. If that is correct, then that would mean the JDBC driver does not support a 'feature' of the database that it allows for per-table charset. Or is there a way to get it to take those charsets into account?

Unable to create initial connections of pool. com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. (3 replies)

Suresh Barkur — Tue, 19 Mar 2024 22:55:17 +0000

Hi Team

I am stuck with below error , Although the connection is successful to localhost but still getting below mentioned error

SEVERE [main] org.apache.tomcat.jdbc.pool.ConnectionPool.init Unable to create initial connections of pool. com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.

Any Insight to the issue will be helpful

Regards

Aletrnative to ParseURL in Connector/J version (8 replies)

Mustajib Khan — Fri, 08 Dec 2023 20:40:23 +0000

Hi,
with the removal of parseURL from com.mysql.jdbc.NonRegisteringDriver is there an alternative we have for this in version 8?

Performance degradation after upgrading to MySQL 8 (4 replies)

Reddy Venkata Hanuma Kishore — Tue, 14 Nov 2023 03:55:40 +0000

We have upgraded MySQL in our application from version 5.7.43 to version 8.0.35.
We are getting below exception while trying the fetch the records from the database.

231104 04:04:03 : com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Application was streaming results when the connection failed. Consider raising value of 'net_write_timeout' on the server.
231104 04:04:03 : at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
231104 04:04:03 : at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
231104 04:04:03 : at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
231104 04:04:03 : at java.lang.reflect.Constructor.newInstance(Constructor.java:423)

We tried increasing the net_write_timout value but it didnt help.
Could anyone please provide your suggesstions?

MySQL Connector/J 2FA and FIDO (WebAuthn) (no replies)

Edwin Desouza — Mon, 30 Oct 2023 22:59:27 +0000

MySQL Connector/J 2FA and FIDO (WebAuthn)
- https://blogs.oracle.com/mysql/post/mysql-connectorj-fido-webauthn

mysql-connector 8.0.32 exception : java.lang.IllegalArgumentException: HOUR_OF_DAY: 2 -> 3 (3 replies)

TEST TEST — Sat, 23 Sep 2023 00:10:52 +0000

mysql-server version: 8.0.32
mysql-connector version: 8.0.32

details :
1. we deploy two database nodes (for example, A and B).
2. one is CST,and the other is PDT.
3. data sync from A to B;

when A has a record with dateTime : 2023-03-12 02:45:00， this field data will be sync to B。

and query from B has "java.lang.IllegalArgumentException: HOUR_OF_DAY: 2 -> 3" happend.

#com.mysql.cj.result.SqlTimestampValueFactory#localCreateFromDate
- can delete "c.setLenient(false);"

Unable to retrieve the timestamp field after upgrading to Mysql connector for java 8.0.30 (1 reply)

Saravanan Balarishnan — Wed, 09 Aug 2023 02:02:51 +0000

Hi All,

Recently we upgraded our MySQL connector from 5.1.x to 8.0.30 to accommodate the DB server upgrade. After the connector upgrade, application is unable to retrieve the timestamp value from the backend facing IllegalArgumentException from Java Gregorian Calendar API.

Our application and DB server runs on Singapore (GMT+8) Timezone. This exception is happening only for the timestamps when there was offset change happened in Singapore (https://en.wikipedia.org/wiki/Singapore_Standard_Time#Timeline).

Example:

Timestamp in DB - 1982-01-01 00:00:00

Exception when trying to retrieve the timestamp from application - Caused by: java.lang.IllegalArgumentException: MINUTE: 0 -> 30
at java.util.GregorianCalendar.computeTime(GregorianCalendar.java:2829)

Tried using serverTimeZone, connectionTimeZone in the connection url but still the issue persists.

Any help is highly appreciated.

Thanks

Procedure runs fine in DB but throwing errors while running within integration tests (2 replies)

Ishan Jain — Mon, 05 Jun 2023 11:37:12 +0000

I have the below procedure which I wanted to run before each test in my application integration tests to quickly truncate all tables in my schema:
But this does not work in integration test run while it runs fine in a DB

DELIMITER //
CREATE PROCEDURE truncate_tables()
BEGIN
DECLARE tblName CHAR(200);
DECLARE done INT DEFAULT FALSE;
DECLARE dbTables CURSOR FOR
SELECT table_name
FROM information_schema.tables
WHERE table_schema = (SELECT DATABASE());
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

OPEN dbTables;
SET FOREIGN_KEY_CHECKS = 0;

read_loop: LOOP
FETCH dbTables INTO tblName;
IF done THEN
LEAVE read_loop;
END IF;
SET @s = CONCAT('TRUNCATE TABLE ', tblName);
PREPARE stmt FROM @s;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
END LOOP read_loop;

CLOSE dbTables;
SET FOREIGN_KEY_CHECKS = 1;
END
//

CALL truncate_tables();
DROP PROCEDURE IF EXISTS truncate_tables;

Longtext Column Values getting hex encoded by jdbc driver (1 reply)

Zac Burke — Tue, 18 Apr 2023 11:22:37 +0000

Hello,

I was developing a simple Java application to save some data to a mysql database using the latest version of the jdbc connector mysql-connector-j-8.0.32 , and jdk 17.

I have enabled query logging on the database as follows:

SET global general_log_file='/tmp/mysql.log';
SET global log_output = 'file';
SET global general_log = on;

While my java application (JDK17) was running and inserting data to the relevant table, I noticed that the jdbc driver is hex encoding all values for columns of type longtext.

I could see this via the inserts in the query log, which I was tailing as the program was running.

As I was using many frameworks (hibernate / spring) I wrote a simple main line program just with the jdbc driver jar as a dependency to see if it was any of the other
frameworks causing the problem.

However, I still see this behaviour of the longtext values getting hex encoded by the jdbc driver, with just the jdbc dependency

I have a simple main line program which is using the mysql jdbc driver on its own and a simple table called book.
create table book
(
id bigint auto_increment primary key,
author varchar(255) null,
extract_a longtext null,
extract_b longtext null,
extract_c longtext null,
num_pages int not null,
title varchar(200) null
);

Using a standard prepared statement and normal jdbc code I insert a simple row into the database. The values I send down via java code are:

'Stephen King','Extract A.','Extract B.','Extract C.',200,'The Shining'

The query log shows me the following:

Query INSERT INTO book (author, extract_a, extract_b, extract_c, num_pages,title)
VALUES ('Stephen King', x'4578747261637420412e', x'4578747261637420422e', x'4578747261637420432e', 200, 'The Shining')

It can be clearly seen that it is sending down the values as hex encoded strings x followed by 4578747261637420412e, which is the value 'Extract A' as a hex encoded string. The same goes for the other longtext columns,

It's worth noting that this appears only to have been introduced from version 8.0.29 of the jdbc driver. Versions before this were not hex-encoding values of longtext.

My question is:

Is this a deliberate change (i.e) That all longtext columns are now hex encoded by the jdbc driver? and is there no way of turning this off ?
It's just that with hex encoding the amount of data sent down to the server will be in most cases twice as much.

The values I have chosen in my example are quite small just to show my point, but my real-world values will be quite large, and I'd like to understand if this overhead of hex encoding the data will always be there.

I had a look to see if this was called out anywhere in the release notes , but was unable to find any such information.

Thanks for taking the time to read this far !

-Zac.

My Version of MySQL Server is
Server version: 8.0.32 MySQL Community Server - GPL Running on Mac OS

MySQL [(none)]> show variables like '%char%';
+--------------------------+-------------
| Variable_name | Value |
+--------------------------+-------------
| character_set_client | utf8mb3 |
| character_set_connection | utf8mb3 |
| character_set_database | utf8mb4 |
| character_set_filesystem | binary |
| character_set_results | utf8mb3 |
| character_set_server | utf8mb4 |
| character_set_system | utf8mb3

The my.cnf has nothing out of the ordinary in it , I'm just setting the basedir, datadir and tmp dir values.

cannot be cast to class com.mysql.cj.jdbc.ClientPreparedStatement (6 replies)

Tomonori Iida — Tue, 18 Apr 2023 11:01:29 +0000

Hi
We are developing a multi-threaded batch application on Spring Boot 2.7.8 + Aurora MySQL 2.11.1 (primary-db/replica-db).
I am having trouble with ClassCastException when updating/inserting data into a table.
If I update only one item, ClassCastException is not raised.
Only when updating a large number of n updates, the ClassCastException is always thrown.
Also, when I connect with MariaDB Connector/J 2.5.4 instead of MySQL Connector/J 8.0.32, no ClassCastException occurs even for mass updates.
I would say that using MariaDB Connector/J would solve the problem, but..,

# HikariCP
## MySQL Connector/J
- name: "default"
dataSource:
driverClassName: "com.mysql.cj.jdbc.Driver"
jdbcUrl: "jdbc:mysql:replication://\
primary-db:3306\
,replica-db:3306\
?rewriteBatchedStatements=true&sessionVariables=character_set_connection=utf8mb4,collation_connection=utf8mb4_general_ci&socketTimeout=300000"
username: "root"
password: ""
autoCommit: true
readOnly: false
connectionTimeout: 300000
idleTimeout: 600000
minimumIdle: 2
maximumPoolSize: 10
connectionTestQuery: "SELECT 1"

## MariaDB Connector/J
hikari:
- name: "default"
dataSource:
driverClassName: "org.mariadb.jdbc.Driver"
jdbcUrl: "jdbc:mysql:aurora://\
primary-db:3306\
,replica-db:3306\
?rewriteBatchedStatements=true&sessionVariables=character_set_connection=utf8mb4,collation_connection=utf8mb4_general_ci&socketTimeout=300000"
username: "root"
password: ""
autoCommit: true
readOnly: false
connectionTimeout: 300000
idleTimeout: 600000
minimumIdle: 2
maximumPoolSize: 10
connectionTestQuery: "SELECT 1"

# ClassCastException
2023-xx-xx xx:yy:zz [ForkJoinPool-4-worker-23] ERROR o.h.e.j.b.i.BatchingBatch -> HHH000315: Exception executing batch [java.lang.ClassCastException: class com.sun.proxy.$Proxy186 cannot be cast to class com.mysql.cj.jdbc.ClientPreparedStatement (com.sun.proxy.$Proxy186 and com.mysql.cj.jdbc.ClientPreparedStatement are in unnamed module of loader org.springframework.boot.loader.LaunchedURLClassLoader @7823a2f9)], SQL: update test.table1 set updated_at=?, account_id=?, hoge_formats=?, hoge_type=?, body=?, action_type=?, cr_type=?, story_id=?, hash=?, name=?, story_spec=?, object_type=?, status=?, title=?, video_id=? where id=?

# DDL
CREATE TABLE `test`.`table1` (
`id` bigint(20) NOT NULL,
`account_id` varchar(128) NOT NULL,
`hash` varchar(128) DEFAULT NULL,
`video_id` varchar(128) DEFAULT NULL,
`action_type` varchar(128) DEFAULT NULL,
`title` varchar(512) DEFAULT NULL,
`body` mediumtext,
`name` varchar(256) DEFAULT NULL,
`story_id` varchar(192) DEFAULT NULL,
`object_type` varchar(32) DEFAULT NULL,
`cr_type` varchar(32) NOT NULL,
`status` varchar(64) NOT NULL,
`story_spec` json DEFAULT NULL,
`hoge_type` varchar(128) DEFAULT NULL,
`hoge_formats` varchar(255) DEFAULT NULL,
`created_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
`updated_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`id`),
KEY `idx_accid` (`account_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

# Entity
@EqualsAndHashCode(callSuper = false)
@Builder
@NoArgsConstructor
@AllArgsConstructor(staticName = "of")
@Data
@Entity
@Table(catalog = "test", name = "table1")
public class Table1 extends BaseEntity {
private static final long serialVersionUID = 1L;
@Id
private BigInteger id;
private String accountId;
private String hash;
private String videoId;
@Enumerated(EnumType.STRING)
private ActionType actionType;
private String title;
private String body;
private String name;
private String storyId;
@Enumerated(EnumType.STRING)
private ObjectType objectType;
@Convert(converter = CrTypeToStringConverter.class)
private CrType crType;
@Enumerated(EnumType.STRING)
private Status status;
@Convert(converter = StorySpecToStringConverter.class)
private StorySpec storySpec;
@Enumerated(EnumType.STRING)
private HogeType hogeType;
@Convert(converter = StringsToStringConverter.class)
private List hogeFormats;
}

Please advise if you have any suggestions.

MySQL Connector/J 5.1: NPE when executing SQL with QueryTimeout>0 on fabric connection (3 replies)

Chengdong He — Mon, 24 Jul 2023 10:13:46 +0000

When executing sql with QueryTimeout settings, getProperties() in class FabricMySQLConnectionProxy gets NULL when constructing CancelTask resulting in NPE.
And sql with QueryTimeout settings is a common connection availability detection method in connection pool (e.g. tomcat built-in connection pool, druid connection pool). So this may cause the connection availability detection to fail, resulting in unpredictable behavior such as connection pools abandoning available connections.

Bug regarding rewritableAsMultiValues introduced in 8.0.29 (8 replies)

Gustaf Sörensen — Tue, 31 Jan 2023 17:56:24 +0000

After bumping to 8.0.29 and later versions we noticed that batch inserts made by prepared statements took much longer time to execute. After a bit of investigation we found that this only happens on some of our inserts. Namely inserts where we have column names that have the word "value" in them and where the query takes placeholders "?".

We could find no way to work around this so please provide a fix since we can't go above 8.0.28 until this is resolved.

Including is a test verifying the bug:

import static org.junit.jupiter.api.Assertions.assertTrue;

import com.mysql.cj.jdbc.ClientPreparedStatement;
import com.mysql.cj.jdbc.MysqlDataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import org.junit.jupiter.api.Test;

class TransferDatabaseTest {
@Test
void rewritableAsMultiValuesBug() throws SQLException {
MysqlDataSource dataSource = new MysqlDataSource();
String url = "YOUR CONNECTION STRING GOES HERE :)";
dataSource.setURL(url);
dataSource.setRewriteBatchedStatements(true);
Connection connection = dataSource.getConnection();

//WORKING QUERY
PreparedStatement preparedStatement = connection.prepareStatement(
"INSERT INTO test (a, b) VALUES (?, ?)"
);
ClientPreparedStatement clientPreparedStatement = (ClientPreparedStatement) preparedStatement;
boolean isRewritable = clientPreparedStatement.getQueryInfo()
.isRewritableWithMultiValuesClause();
assertTrue(isRewritable);
connection.close();

//FAILING QUERY
connection = dataSource.getConnection();
PreparedStatement preparedStatementBug = connection.prepareStatement(
"INSERT INTO test (a_value, bvalue) VALUES (?, ?)"
);
ClientPreparedStatement clientPreparedStatementBug = (ClientPreparedStatement) preparedStatementBug;
boolean isRewritableBug = clientPreparedStatementBug.getQueryInfo()
.isRewritableWithMultiValuesClause();
assertTrue(isRewritableBug);

}

}

why mysql jdbc driver of com.mysql.cj.Messages always reference String not release memory (1 reply)

star zhang — Mon, 09 Jan 2023 12:09:24 +0000

In our project, have call mysql driver
But I don't know why have a String object, Not release memory
an when have a SQL query, the String Object will be have again, and at the last will be out of memory.

the String is like this, and have so many the same String in dump heap profile.

value of java.lang.String ["By default, network connections are SSL encrypted; this property permits secure connections to be turned off, or a different levels of security to be chosen. The following values are allowed: "DISABLED" - Establish unencrypted connections; "PREFERRED" - (default) Establish encrypted connections if the server enabled them, otherwise fall back to unencrypted connections; "REQUIRED" - Establish secure connections if the server enabled them, fail otherwise; "VERIFY_CA" - Like "REQUIRED" but additionally verify the server TLS certificate against the configured Certificate Authority (CA) certificates; "VERIFY_IDENTITY" - Like "VERIFY_CA", but additionally verify that the server certificate matches the host to which the connection is attempted.[CR] This property replaced the deprecated legacy properties "useSSL", "requireSSL", and "verifyServerCertificate", which are still accepted but translated into a value for "sslMode" if "sslMode" is not explicitly set: "useSSL=false" is translated to "sslMode=DISABLED"; '{'"useSSL=true", "requireSSL=false", "verifyServerCertificate=false"'}' is translated to "sslMode=PREFERRED"; '{'"useSSL=true", "requireSSL=true", "verifyServerCertificate=false"'}' is translated to "sslMode=REQUIRED"; '{'"useSSL=true" AND "verifyServerCertificate=true"'}' is translated to "sslMode=VERIFY_CA". There is no equivalent legacy settings for "sslMode=VERIFY_IDENTITY". Note that, for ALL server versions, the default setting of "sslMode" is "PREFERRED", and it is equivalent to the legacy settings of "useSSL=true", "requireSSL=false", and "verifyServerCertificate=false", which are different from their default settings for Connector/J 8.0.12 and earlier in some situations. Applications that continue to use the legacy properties and rely on their old default settings should be reviewed.[CR] The legacy properties are ignored if "sslMode" is set explicitly. If none of "sslMode" or "useSSL" is set explicitly, the default setting of "sslMode=PREFERRED" applies. "]

Help I don't know why my Timestamp statement in JAVA for certain fields is only giving me null on the Server (2 replies)

Juan Pablo Mendoza Ayala — Wed, 21 Dec 2022 20:06:01 +0000

Help I need a solution idk why but when making the backend for a project when assigning a Timestamp variable to creation date and modification date if I run a JSON using Postman it just gives me Null like I've tried everything but can't figure it out

asSql() method is removed from ClientPreparedStatement (2 replies)

Ken Van Camp — Sat, 24 Dec 2022 16:17:05 +0000

In the mysql-connector-java library, ClientPreparedStatement had a public method called asSql(). The function was there in the 8.0.28 jar (Jan 17, 2022) but removed in 8.0.29 (Apr 25, 2022). I recognize that this is not part of the published JDBC interface, so I cannot legitimately call it a “bug”, but it was a public method and was not deprecated, and it was a very useful function for me. I used it in a QueryInterceptor which allowed me to give a meaningful name to AWS X-ray subsegments. I tried using toString() which I see invokes asSql(), but it prepends the class name which I then have to strip off.

The method was removed on Jan 17, 2022 by soklakov in commit 4c98c11eb93dd56c01b9f5945f0e16137c585a39.

Is there some recommended way for me to get the query from the ClientPreparedStatement, or its underlying this.query object since that has the asSql() function?

JDBC connection error (1 reply)

Erica Maselli — Fri, 16 Dec 2022 22:10:20 +0000

Hello everyone,

I state that I am a neophyte; I have a problem when I try to connect with jdbc both of the tomcat docker container and of a local host to the postgresql container I get this error:

"" org.postgresql.util.PSQLException: The connection attempt failed.
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:315) ~[postgresql-42.2.23.jar:42.2.23] "" etc.... etc....

The postgres accepts all incoming connections I've already checked

Who can help me?

Using Azure JDBC authentication plugin with MysqlConnectionPoolDataSource throw exception. (1 reply)

guo zhihao — Thu, 05 Jan 2023 11:27:48 +0000

Hi all:
I am using mysql-connector-java(mysql-connector-j) and extended AuthenticationPlugin in com.azure:azure-identity-providers-jdbc-mysql:1.0.0-beta.1 to connect Azure hosted MySQL server.
In this way, instead of authenticating with username/password, I can use the AuthenticationPlugin to perform authentication with username/accessToken.

But the accessToken is very long(about 1767 characters), and when I was using MysqlConnectionPoolDataSource, I encounted an issue: https://github.com/Azure/azure-sdk-for-java/issues/31599.

Question:
I have a workaround to fix this as the doc says, but still I have a question: why there is a 256 limitation here:https://github.com/mysql/mysql-connector-j/blob/27603148f10a5f47467bec7ad26a5ca28da63c72/src/main/protocol-impl/java/com/mysql/cj/protocol/a/NativeAuthenticationProvider.java#L679-L685.

I would appreciate it if any one could help me with this question.

Thanks.