OBLOADER & OBDUMPER V4.2.8.2

OBLOADER & OBDUMPER V4.2.8.2 released in March 2024 has fixed some known issues.

Version information

• Current version: V4.2.8.2

• Previous version: V4.2.8.1

• Release date: March 11, 2024

Considerations

• OBLOADER & OBDUMPER V4.2.8 and later allow you to specify the value of -u/--user in the three-segment format of <user\>@<tenant\>#<cluster\>. For backward compatibility, you can still use the -t/--tenant and -c/--cluster options.

• When you use the --storage-uri option in a data import/export scenario involving Alibaba Cloud Object Storage Service (OSS) or Hadoop Distributed File System (HDFS), the -f/--file-path option is no longer a must. OBLOADER & OBDUMPER will automatically create a temporary directory /tmp in its root directory for storing logs and checkpoint files.

  Notice

  This modification applies only in a debugging environment. In a production environment, we recommend that you use the -f or --log-path option to specify the log storage directory.

• The behavior for parsing POS files is changed. In this version, the parser processes a whole line. In other words, in addition to the byte length defined in the control file, the parser will further read a line break for each line. You may need to modify the control file to adapt to this change. You can run the following command to calculate the number of bytes in the first line of the example.dat file: expr $(head -n 1 example.dat | wc -c) - 1.

• Schema export performance optimization is supported for Oracle tenants of OceanBase Database only in the following scenarios:

  • The --no-sys option is used in the export for an Oracle tenant of OceanBase Database of a version earlier than V4.0.0.

  • The --compact-schema option is used in the export for an Oracle tenant of OceanBase Database V4.0.0 or later.

Bug fixes

• Fixed the issue where the table schema is exported when you specify to export the schema of a non-table object.

• Fixed the issue where the data of all partitions of the table may be exported when you use the --partition option to export the data of a specific partition.

• Fixed the syntax defects in the batch processing script for Windows.

• Fixed the issue where a NullPointerException (NPE) error occurs if the -t/--tenant option is not specified when you export data from ApsaraDB for OceanBase.

Known issues

• The exported database object definitions may contain the name of the database to which the object belongs.

• OBDUMPER cannot export PL object definitions from OceanBase Database of a version earlier than V2.2.30 in MySQL mode.

• If you do not specify the password of the sys tenant on the command line, OBDUMPER cannot export table group definitions from OceanBase Database of a version earlier than V2.2.70.

• If you do not specify the password of the sys tenant on the command line, OBDUMPER cannot export index definitions from OceanBase Database of a version earlier than V2.2.50 in Oracle mode.

• If you do not specify the password of the sys tenant on the command line, OBDUMPER cannot export partition information of unique indexes from OceanBase Database of a version earlier than V2.2.70 in Oracle mode.

• If you do not specify the password of the sys tenant on the command line, OBDUMPER cannot export definitions of unique indexes on partitioned tables from OceanBase Database V2.2.70 or later in Oracle mode.

• When you use OBLOADER to import data, an error occurs if the specified file format, such as --sql or --csv, does not match the actual file format.

• After you enable case sensitivity for object names, such as table names and view names, in OceanBase Database in MySQL mode, objects are imported or exported in a case-insensitive manner.

• The high-availability mode “sequential” of OceanBase Connector/J is unavailable for now. You can use the “loadbalance” mode instead.

• If you specify the --remove-newline option to remove line breaks, unexpected escape characters will be generated. Therefore, we recommend that you do not use this option.

• If you use bypass import in a multi-table restore scenario, the performance may be undesirable.

Considerations

• In a CUT file, each data record is stored in an entire line. When you specify the --cut option on the OBDUMPER command line, if the exported data contains a single-character field separator, OBDUMPER escapes special characters in the data, such as separators, carriage returns, and line breaks. For example, if the data is abc|def and the separator is |, the exported data is abc\|def.

• When you specify the --cut option on the OBLOADER command line, do not use the --trail-delimiter option if no field separator or separator string exists at the end of each data line in the file. Otherwise, the data cannot be correctly imported to the database.

• If you specify the --logical-database option on the command line, the definition of a random physical database shard is exported and the shard cannot be directly imported into the database. You need to manually convert the exported physical shard to a logical one before you import it to the database for business use.

• When you specify the --partition option on the command line to export data in a partition, you need to specify the name of the subpartition for a composite partitioned table. OBDUMPER cannot export data in a partition of a composite partitioned table. If the specified partition name does not exist, OBDUMPER returns an error.

• If you specify the --add-extra-message option on the command line to export table definitions, OBDUMPER exports the name of the table group to which each table belongs. This option depends on privileges of the sys tenant. If OBDUMPER does not have privileges of the sys tenant, do not specify this option.

• When you use OBLOADER & OBDUMPER to import data to or export data from OceanBase Database V3.2.4 or later, set the open_cursors system parameter to a large value. Otherwise, an error may occur during the import or export. After the data is imported or exported, reset the system parameter to the initial value, such as ALTER SYSTEM SET open_cursors = 65535;.

• In OceanBase Database V4.0.0 or later, if the schema of a table has been changed, you cannot use OBDUMPER to export the baseline data, namely the consistent snapshot data, obtained after the last major compaction. You can manually initiate a major compaction and then export the most recent baseline data.

• When you use OBDUMPER of a version earlier than V4.2.0 to export data from a MySQL tenant of OceanBase Database, OceanBase Connector/J converts the zero values of date and time type fields in the database to NULL. If a column has a NOT NULL constraint, an error will be reported during the export. OBDUMPER V4.2.0 can export zero values of date and time type fields, but cannot identify whether the original data is NULL or zero values during export and forcibly converts the data to zero values by default. In addition, exported zero values of the DATETIME and TIMESTAMP data types may be distorted into non-zero approximate values. If the sql_mode variable in the database is specified with the NO_ZERO_DATE or NO_ZERO_IN_DATE constraint, an error will be reported when zero-value data is exported. Take note of this consideration on zero values when you export data of the DATE, DATETIME, TIME, YEAR, or TIMESTAMP type from a MySQL tenant of OceanBase Database.

• Feature differences in schema export in Oracle and MySQL tenants