Describe the bug

报错信息：
Suppressed: java.lang.ClassCastException: java.util.LinkedHashMap$Entry cannot be cast to java.util.HashMap$TreeNode at java.util.HashMap$TreeNode.moveRootToFront(HashMap.java:1835) ~[?:1.8.0_242] at java.util.HashMap$TreeNode.treeify(HashMap.java:1951) ~[?:1.8.0_242] at java.util.HashMap.treeifyBin(HashMap.java:772) ~[?:1.8.0_242] at java.util.HashMap.putVal(HashMap.java:644) ~[?:1.8.0_242] at java.util.HashMap.put(HashMap.java:612) ~[?:1.8.0_242] at com.oceanbase.jdbc.OceanBaseConnection.getCachedSql(OceanBaseConnection.java:612) ~[oceanbase-client-2.4.1.jar!/:?] at com.oceanbase.jdbc.OceanBaseConnection.internalPrepareStatement(OceanBaseConnection.java:643) ~[oceanbase-client-2.4.1.jar!/:?] at com.oceanbase.jdbc.OceanBaseConnection.prepareStatement(OceanBaseConnection.java:438) ~[oceanbase-client-2.4.1.jar!/:?] at com.p6spy.engine.wrapper.ConnectionWrapper.prepareStatement(ConnectionWrapper.java:118) ~[p6spy-3.7.0.jar!/:?] at com.zaxxer.hikari.pool.ProxyConnection.prepareStatement(ProxyConnection.java:337) ~[HikariCP-4.0.3.jar!/:?] at com.zaxxer.hikari.pool.HikariProxyConnection.prepareStatement(HikariProxyConnection.java) ~[HikariCP-4.0.3.jar!/:?] at org.springframework.jdbc.core.JdbcTemplate$SimplePreparedStatementCreator.createPreparedStatement(JdbcTemplate.java:1556) ~[spring-jdbc-5.2.24.RELEASE.jar!/:5.2.24.RELEASE] at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:615) ~[spring-jdbc-5.2.24.RELEASE.jar!/:5.2.24.RELEASE] at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:669) ~[spring-jdbc-5.2.24.RELEASE.jar!/:5.2.24.RELEASE] at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:700) ~[spring-jdbc-5.2.24.RELEASE.jar!/:5.2.24.RELEASE] at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:753) ~[spring-jdbc-5.2.24.RELEASE.jar!/:5.2.24.RELEASE]

Environment

版本：oceanbase-client-2.4.1.jar

Fast reproduce steps

频繁查询即可触发

Expected behavior

No response

Actual behavior

No response

Additional context

No response

针对IDEA连接oceanbase数据库获取不到注释的建议，我的做法是join user_col_comments 表 关联查询出字段对应的comments

Describe the bug

When using the driver without the useInformationSchema option the getTables REMARK column returns
the result of new byte[0].toString(); which results in values like [B@78aab498

Environment

For any version of the obconnector-j, I used 2.4.10
For any JDBC SQL client, I used sqlline

Fast reproduce steps

JDBC Connection string without the useInformationSchema option.

Expected behavior

sqlline> !connect jdbc:oceanbase://172.16.4.198:2881/db1

0: jdbc:oceanbase://172.16.4.198:2881/db1> !tables
+-----------+-------------+------------+------------+-------------+----------+------------+-----------+---------------------------+----------------+
| TABLE_CAT | TABLE_SCHEM | TABLE_NAME | TABLE_TYPE |   REMARKS   | TYPE_CAT | TYPE_SCHEM | TYPE_NAME | SELF_REFERENCING_COL_NAME | REF_GENERATION |
+-----------+-------------+------------+------------+-------------+----------+------------+-----------+---------------------------+----------------+
| db1       |             | results    | TABLE      |             |          |            |           |                           |                |
| db1       |             | stuff      | TABLE      |             |          |            |           |                           |                |
| db1       |             | zot        | TABLE      |             |          |            |           |                           |                |
+-----------+-------------+------------+------------+-------------+----------+------------+-----------+---------------------------+----------------+

Actual behavior

sqlline> !connect jdbc:oceanbase://172.16.4.198:2881/db1

0: jdbc:oceanbase://172.16.4.198:2881/db1> !tables
+-----------+-------------+------------+------------+-------------+----------+------------+-----------+---------------------------+----------------+
| TABLE_CAT | TABLE_SCHEM | TABLE_NAME | TABLE_TYPE |   REMARKS   | TYPE_CAT | TYPE_SCHEM | TYPE_NAME | SELF_REFERENCING_COL_NAME | REF_GENERATION |
+-----------+-------------+------------+------------+-------------+----------+------------+-----------+---------------------------+----------------+
| db1       |             | results    | TABLE      | [B@33afa13b |          |            |           |                           |                |
| db1       |             | stuff      | TABLE      | [B@56a6d5a6 |          |            |           |                           |                |
| db1       |             | zot        | TABLE      | [B@18ce0030 |          |            |           |                           |                |
+-----------+-------------+------------+------------+-------------+----------+------------+-----------+---------------------------+----------------+

Additional context

The line that produces the invalid column values in version 2.4.10 is
JDBC4DatabaseMetaData.java:1014
data[4] = new byte[0].toString();

Describe your use case

OceanBase Client for Go

Describe the solution you'd like

Just curious if OB has any plan to develop a client in Go.
As more and more developers are using Golang to develop applicaations, Java and C/C++ drivers are far from enough.

And Oracle, for example, has go-ora driver, which can be added to the Go application:

• Connect to Oracle Database Using go-ora Library
• Working in Go applications with Oracle Database

Describe alternatives you've considered

No response

Additional context

No response

Describe the bug

通过jdbc oracle企业版在查询海量数据的时候，如1亿以上，报OOM。同样代码在ORACLE下无问题，部分代码如下：
stmt = conn.prepareStatement(sql,
ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY, ResultSet.HOLD_CURSORS_OVER_COMMIT);
stmt.setFetchDirection(ResultSet.FETCH_FORWARD);
stmt.setFetchSize(1000);
rs = stmt.executeQuery(); // 内存溢出

Environment

驱动版本2.4.3

Fast reproduce steps

/

Expected behavior

No response

Actual behavior

No response

Additional context

No response

Describe the bug

When I run a java code to connect to Oceanbase and I set the default time zone to UTC or GMT+00:00, an exception will be throwed:

Failed to establish a connection: Could not connect to *****:2881 : (conn=3221584558) The server time_zone 'GMT+08:00' defined in the 'serverTimezone' parameter cannot be parsed by java TimeZone implementation. See java.util.TimeZone#getAvailableIDs() for available TimeZone, depending on your JRE implementation.
java.sql.SQLTransientConnectionException: Could not connect to ******:2881 : (conn=3221584558) The server time_zone 'GMT+08:00' defined in the 'serverTimezone' parameter cannot be parsed by java TimeZone implementation. See java.util.TimeZone#getAvailableIDs() for available TimeZone, depending on your JRE implementation.
        at com.oceanbase.jdbc.internal.util.exceptions.ExceptionFactory.createException(ExceptionFactory.java:128)
        at com.oceanbase.jdbc.internal.util.exceptions.ExceptionFactory.create(ExceptionFactory.java:235)
        at com.oceanbase.jdbc.internal.protocol.AbstractConnectProtocol.connectWithoutProxy(AbstractConnectProtocol.java:1644)
        at com.oceanbase.jdbc.internal.util.Utils.retrieveProxy(Utils.java:1427)
        at com.oceanbase.jdbc.OceanBaseConnection.newConnection(OceanBaseConnection.java:306)
        at com.oceanbase.jdbc.Driver.connect(Driver.java:89)
        at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:681)
        at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:229)
        at com.example.apecloud.DatabaseManager.getConnection(DatabaseManager.java:67)
        at com.example.apecloud.DatabaseManager.testConnection(DatabaseManager.java:39)
        at com.example.Main.getConn(Main.java:159)
        at com.example.Main.main(Main.java:42)

Environment

Mac and Java.

Fast reproduce steps

String tz = "GMT" + "+00:00";
TimeZone timeZone = Utils.getTimeZone(tz);
TimeZone.setDefault(timeZone);
String host=1.2.3.4
String jdbcUrl = "jdbc:oceanbase://" + host + ":2881/TEST?serverTimezone=Asia/Shanghai";
String username = "TEST@test";
String password = "123455";
return DriverManager.getConnection(jdbcUrl, username, password);

Expected behavior

Connect to the Oceanbase successfully.

Actual behavior

Throw exception.

Additional context

I analyzed the source code, and I believe the issue lies within the sendAlterSessionTimezone function.

    private void sendAlterSessionTimezone() throws IOException, SQLException {
        this.importedTimeZoneTables = getServerTZTablesImported();
        String zoneId = this.importedTimeZoneTables ? TimeZone.getDefault().getID()
            : TimeZone.getDefault().toZoneId().getRules().getStandardOffset(Instant.now()).getId();
        // when importedTimeZoneTables is
        //   false: the TIME_ZONE cannot be set to any values that start with "GMT"
        //   true: only GMT, GMT+0, GMT-0, GMT0 can be accepted
        if (zoneId.startsWith("GMT") && (!this.importedTimeZoneTables
                || !zoneId.equalsIgnoreCase("GMT")|| !zoneId.equalsIgnoreCase("GMT+0")
                || !zoneId.equalsIgnoreCase("GMT-0") || !zoneId.equalsIgnoreCase("GMT0"))) {
            zoneId = zoneId.substring("GMT".length());
        }

        writer.startPacket(0);
        writer.write(Packet.COM_QUERY);
        writer.write(ALTER_SESSION_TIMEZONE_QUERY);
        writer.write(zoneId.getBytes());
        writer.write('\'');
        writer.flush();
    }

When the default timezone is UTC, the TimeZone.getDefault().toZoneId().getRules().getStandardOffset(Instant.now()).getId() will return Z, and Z is not a valid timezone for alter session set TIME_ZONE that will throw an exception, unfortunately, this exception message is not been printed, so it is difficult to clearly see where the problem lies.

IMO, this function should check if the zoneId is Z, if yes, convert it to a valid timezone format.

Describe the bug

create table T4(ID BINARY_FLOAT);
insert into T4 values(1.2);

然后通过jdbc 使用select 查询这个表,当调用resultSet.getObject()方法时驱动会报错,驱动用的oceanbase-client:2.4.3
错误的位置在下面截图这里:

这里直接new String(bytes) 没看懂..

下面用Float.intBitsToFloat转换能正常显示出插入值 1.2