Limitations

This topic describes the environment requirements for deploying OceanBase Developer Center (ODC) and the limitations on each feature module.

Web ODC

Client ODC

Feature support of different data source types

Limitations on data source versions

Limitations on using features

Permission limitations

• To perform debugging in OceanBase Database V4.0.0 and later, make sure that you have the debugging permissions. You can execute the GRANT DEBUG CONNECT SESSION TO <user> or GRANT DEBUG ANY PROCEDURE TO <user> statement to grant the debugging permissions.

• In ODC of a version earlier than V4.1.3-bp4, a user configured in an OceanBase MySQL data source must have permissions on mysql.proc. Otherwise, an error occurs when the user views functions or stored procedures in the data source.

• In ODC of a version earlier than V4.1.0, if you want to export objects other than tables and views from an OceanBase data source or if you want to ensure the export speed for the OceanBase data source, you must configure a sys tenant account that has query permissions on the sys tenant.

• In ODC V4.1.0 and later, if you want to ensure the export speed for an OceanBase data source, you must configure a sys tenant account that has query permissions on the sys tenant.

Session limitations

• ODC of a version earlier than V4.2.0 supports the shared session mode. In shared session mode, all windows in a connection share a session. If you trigger a commit or rollback operation in any window, including implicit commit scenarios, for example, if you create, modify, or drop a database object schema or execute a DDL statement, the commit or rollback operation affects all windows. For more information about the shared session and independent session modes, see How do I change the session mode in the SQL window?

• In ODC of a version later than V2.3.2, by default, transactions need to be manually committed in Oracle mode of OceanBase Database. For information about how to change the transaction commit mode, see How do I change the transaction commit mode?

• ODC supports the manual commit and auto-commit modes. In manual commit mode, you must set the ob_trx_idle_timeout parameter to an appropriate value for an OceanBase data source. This is to prevent a connection from being terminated because the execution interval between two consecutive SQL statements in a transaction exceeds the value of ob_trx_idle_timeout. Generally, the value of the ob_trx_idle_timeout parameter must be greater than the timeout value of SQL queries. If you specify an excessively large value for this parameter, the memory resources occupied by this session cannot be released in a timely manner. Proceed with caution.

PL limitations

The following table lists the PL support information of ODC.

Limitations on SQL development

• You cannot edit a result set that contains fields of the SET or ENUM data type.

• End-to-end tracing is supported only in OceanBase Database V4.0.0 and later.

Limitations on import and export

• The maximum size of data that can be exported in one batch in Web ODC is 2 GB before compression. To export data of a larger size, use the data export tool OBDUMPER.

• The maximum size of files that can be imported in one batch in Web ODC is 2 GB after compression. To import data of a larger size, use the data import tool OBLOADER.

• At most five concurrent import/export tasks are supported. Subsequent tasks need to wait in the queue.

• By default, files related to import/export tasks are retained for 14 days.

• In ODC V4.1.0 and later, you can configure a sys tenant account for an OceanBase data source to increase the import/export speed. When you export objects other than tables and views, a sys tenant account is no longer a must.

Limitations on change rollback

• A rollback statement can be automatically generated only for the UPDATE and DELETE statements.

• A change task is allowed to affect a maximum of 1 million rows. If the number of affected rows exceeds 1 million, a rollback statement cannot be automatically generated for this change task.

• If the table contains LOB fields, a rollback statement cannot be automatically generated.

• If the table does not have a primary or unique key when the data source is an OceanBase MySQL or a MySQL data source, a rollback statement cannot be automatically generated.

• If the SET and WHERE clauses in an UPDATE statement are the same, a rollback statement cannot be automatically generated.

• The maximum size of a rollback script that is automatically generated is 256 MB.

Limitations on partitioning plans

• Only OceanBase MySQL and OceanBase Oracle data sources are supported.

• Only RANGE-partitioned tables are supported.

• When the upper bound of the last partition in a RANGE-partitioned table reaches the value specified by MAXVALUE, no partition can be created. In this case, you cannot configure partitioning strategies in the Create Partitioning Plan panel.

Limitations on data mocking

• At most 100 million rows can be mocked at a time.

• Data mocking is not supported for a table with CHECK constraints.

• Data mocking is not supported for RANGE- or LIST-partitioned tables.

Limitations on schema comparison

• The following links are supported for schema comparison:

  • Links between MySQL tenants of OceanBase Database

  • Links between Oracle tenants of OceanBase Database

  • Links between MySQL databases

• Only table objects can be compared in terms of columns, primary keys, constraints, indexes, partitions, and attributes.

  • In terms of column attributes, only the data types, character sets, collations, comments, and default values can be compared.

  • Only partitions but not subpartitions can be compared.

  • In terms of table attributes, only the character sets, collations, and comments can be compared.

• CHECK constraints cannot be compared for MySQL tenants of OceanBase Database.

• For a MySQL tenant of OceanBase Database of a version earlier than V1.4.79, you cannot compare partition attributes if you do not have the query permissions on the sys tenant.

Limitations on command-line windows

• Client ODC that runs on macOS does not provide a command-line window.

• You can open at most three command-line windows.

• Operations performed in a command-line window are not recorded.

Limitations on data archiving

• Pay attention to the following rules:

  • Make sure that the fields in the source table are compatible with those at the destination. The data archiving service does not handle field compatibility issues.

  • CPU and memory exhaustion prevention is not supported for a MySQL data source.

  • Schema synchronization is not supported for subpartitions of homogeneous databases. Schema synchronization and automatic table creation are not supported for heterogeneous databases.

• The following archiving links are supported:

  • Links between MySQL tenants of OceanBase Database

  • Links between Oracle tenants of OceanBase Database

  • Links between MySQL databases

  • Links from a MySQL database to a MySQL tenant of OceanBase Database

  • Links from a MySQL tenant of OceanBase Database to a MySQL database

  • Links between Oracle databases

  • Links from an Oracle database to an Oracle tenant of OceanBase Database

  • Links from an Oracle tenant of OceanBase Database to an Oracle database

  • Links from a PostgreSQL database to a MySQL tenant of OceanBase Database

• Data archiving is not supported in the following cases:

  • The source table in the MySQL or OceanBase MySQL data source does not have a primary key or non-null unique index.

  • The source table in the Oracle, OceanBase Oracle, or PostgreSQL data source does not have a primary key.

  • The source table in the OceanBase Oracle data source contains fields of the JSON or XMLType data type.

  • The source table in the PostgreSQL data source contains data of the following types: array, composite, enumeration, geometry, XML, HSTORE, and full-text retrieval.

  • The archiving condition contains a LIMIT clause.

  • The source table contains a foreign key.

• The following archiving links do not support schema synchronization and automatic table creation:

  • Links from an Oracle database to an Oracle tenant of OceanBase Database
  • Links from an Oracle tenant of OceanBase Database to an Oracle database
  • Links from a MySQL database to a MySQL tenant of OceanBase Database
  • Links from a MySQL tenant of OceanBase Database to a MySQL database
  • Links from a PostgreSQL database to a MySQL tenant of OceanBase Database

Limitations on data cleanup

• Pay attention to the following rules:

  • CPU and memory exhaustion prevention is not supported for a MySQL data source.

• Data sources supported for data cleanup are as follows:

  • OceanBase MySQL data sources

  • OceanBase Oracle data sources

  • MySQL data sources

  • Oracle data sources

  • PostgreSQL data sources

• Data cleanup is not supported in the following cases:

  • The source table in the MySQL or OceanBase MySQL data source does not have a primary key or non-null unique index.

  • The source table in the Oracle, OceanBase Oracle, or PostgreSQL data source does not have a primary key.

  • The source table in the OceanBase Oracle data source contains fields of the JSON or XMLType data type.

  • The archiving condition contains a LIMIT clause.

  • The table contains a foreign key.

Limitations on data desensitization

• Data desensitization is not supported in command-line windows.

• Data desensitization is not supported during PL execution.

• When you configure an identification rule script, Groovy supports only the Objects and String classes in Java.

• When you configure an identification rule script, Groovy closures and inherent closure functions are not supported.

• If sensitive data is involved when you export data from a MySQL data source, the mask all algorithm is used for desensitization.

• If sensitive data is involved when you export data from an Oracle data source, the mask all algorithm is used for desensitization.

• If sensitive data is involved when you export data from a Doris data source, the mask all algorithm is used for desensitization.

Limitations on lock-free schema changes

• The table contains a primary key or a non-null unique key, and does not contain a foreign key.

• The table name does not exceed 54 characters in length in MySQL mode of OceanBase Database, and does not exceed 118 characters in Oracle mode.

• When ODC connects to an instance of OceanBase Database Community Edition, the data source configuration information must contain the cluster name and a sys tenant account.

• In Oracle mode of OceanBase Database of a version earlier than V4.0.0 or MySQL mode of OceanBase Database of a version earlier than V4.3.0, ODC locks the user and closes the session to prevent data writes during table name switching.

• If you execute other DDL operations on a table on which a lock-free schema change task is being performed, the task will fail.

• You need to check whether an idle OMS instance exists before using ODC in ApsaraDB for OceanBase to create a lock-free schema change task.

The following table describes the support for lock-free schema changes.

Limitations on batch database changes

• The databases to be changed at a time must belong to the same project.

• The number of databases that can be changed at a time ranges from 2 to 100.

• The databases to be changed at a time cannot be duplicate.

• A batch database change task cannot be aborted when any of its change processes are running. In other words, such a task cannot be aborted if it is automatically executed. If manually executed, however, it can be aborted only when waiting for the next batch of change processes to start.

Limitations on logon integration

• Only the authorization-code mode is supported in OAuth and OIDC.

• When you log off in OAuth or OIDC, only the logon state in ODC is cleared, and the logon state in the SSO system is not cleared.

Limitations on logical databases

• Only MySQL and OceanBase MySQL data sources are supported.

• Only DDL changes are supported.

• Only SQL check specifications and SQL window specifications included in the ODC security specifications are supported.