Limitations

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

Web

Client

Supported data source types

Limitations

Session limitations

• ODC provides two transaction commit modes: manual and automatic. In manual commit mode, if the data source is OceanBase Database, to avoid the session being disconnected due to the execution interval between two SQL statements in a transaction exceeding the value of the ob_trx_idle_timeout parameter, you must set the ob_trx_idle_timeout parameter to a reasonable value. Generally, the value of the ob_trx_idle_timeout parameter must be greater than the SQL query timeout. However, if the value is set too large, the memory occupied by the session cannot be released in time. Therefore, you must set the parameter with caution.

SQL development limitations

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

• Full-link tracing is supported only for OceanBase Database V4.0.0 and later.

• Real-time SQL analysis is supported only for OceanBase Database V4.2.4 and later, and V4.3.3.1 and later.

Import and export limitations

• General limitations:

  • The files involved in import and export tasks are retained for 14 days by default.
  • The total number of records of the exported objects in the details of an export task is not accurate but depends on the views of OceanBase Database.
  • In ODC V4.1.0 and later, you can configure a sys tenant account for OceanBase Database to improve the import and export speed. When you export objects other than tables and views, you do not need to configure a sys tenant account.

• Export limitations:

  • Web ODC has no hard limit on the number of rows in the result set to be exported, but the maximum size of the exported data (before compression) is 2 GB.
  • Web ODC has a limit on the size of the exported data. The maximum size of the exported data (before compression) is 2 GB. If the size exceeds this limit, the data cannot be exported. To export large amounts of data, we recommend that you use the OBDUMPER tool.
  • If a foreign key contains multiple columns, the order of the columns in the foreign key cannot be guaranteed during export. For example, if the foreign key is FOREIGN KEY(c1,c2) REFERENCE ..., the order of c1 and c2 cannot be guaranteed.

• Import limitations:

  • Web ODC has a limit on the size of the uploaded file. The maximum size of the file (after compression) is 2 GB. If the file size exceeds this limit, the file cannot be uploaded. To import large amounts of data, we recommend that you use the OBLOADER tool.
  • If a table with a foreign key is imported, the import may fail because the import order of the related tables cannot be guaranteed.
  • The name of the data file to be imported must be in the same case as the name of the target table.
  • If you import a single table and the data file contains data of other tables, the data of the other tables will also be imported.
  • If you import data by using an SQL file and the SQL file contains a CREATE TABLE statement, the structure will be skipped if it already exists. Only an error message will be recorded in the log.

• Database version limitations:

  • OceanBase Database 1.x and earlier versions.

Change rollback limitations

• Only the UPDATE and DELETE statements can generate rollback statements automatically.

• The maximum number of rows affected by a change statement that can be automatically rolled back is 1,000,000. If the number of rows exceeds this limit, the rollback statement cannot be automatically generated.

• If a table contains large object (LOB) fields, no rollback statement can be automatically generated.

• If a table in an OceanBase Database MySQL data source does not contain a primary key or unique key, no rollback statement can be automatically generated.

• If the modified fields (SET) and the condition fields (WHERE) of an UPDATE statement are the same, no rollback statement can be automatically generated.

• The maximum size of the automatically generated rollback statement script is 256 MB.

Partitioning plan limitations

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

• Only RANGE-partitioned tables are supported.

• If the upper bound of the last partition in a RANGE-partitioned table is MAXVALUE, you cannot add new partitions to the table. Therefore, you cannot create a partitioning strategy by using an ODC partitioning plan task.

• If the involved tables do not exist after a partitioning plan task is issued, the task cannot be executed.

Data mocking limitations

• The maximum number of rows of a single data mock result is 100 million.

• Tables with check constraints cannot be used for data mocking.

• RANGE-partitioned tables and LIST-partitioned tables cannot be used for data mocking.

Schema comparison limitations

• Supported data sources:

  • OceanBase Database MySQL to OceanBase Database MySQL

  • OceanBase Database Oracle to OceanBase Database Oracle

• Only table objects can be compared. The comparison scope includes columns, primary keys, constraints, indexes, partitions, and table attributes.

  • For columns, only the type, character set, collation, comment, and default value can be compared.

  • For partitions, only the primary partitions can be compared. The subpartitions cannot be compared.

  • For table attributes, only the character set, collation, and comment can be compared.

• Check constraints cannot be compared in OceanBase Database MySQL.

• If you use OceanBase Database MySQL V1.4.79 or earlier and do not have the query permissions of the sys tenant, you cannot compare the partition attributes.

Data desensitization limitations

• Data desensitization is not supported for PL execution scenarios.

• When you configure the script of a recognition rule, you can use only the Objects and String classes in Java.

• When you configure the script of a recognition rule, you cannot use Groovy closures or built-in closure functions.

Multi-database change

• Only homogeneous data sources are supported for multi-database change.