Command-line options

OBDUMPER specifies the information to be exported through command-line options. For more information about the options and their usage, see Options and Usage examples.

Overview of options

Option styles

OBDUMPER supports two styles for parameter design: Unix and GNU.

• In the Unix style, a single hyphen (-) is added before the parameter, and the option is a single character. For example: ps -e. In this style, a space is not required between the option and the parameter. For example: -p******.

• In the GNU style, two hyphens (--) are added before the long parameter, and the option can be a single character or a string. For example: ps --version. In this style, a space is required between the option and the parameter. For example: --table 'test'.

Option categories

OBDUMPER command-line options are divided into basic options and advanced options.

• Basic options: These are the commonly used options of OBDUMPER, including connection options (database mode), feature options (file format, database object type, storage path), and other options.

• Advanced options: These include feature options (timestamp format, table/column blocklist and allowlist filtering, error handling) and performance options.

Required options

When you use OBDUMPER to export data, you must specify at least the connection options, format options, database object type options, and storage path options.

Sample statement:

$./obdumper -h xx.x.x.x -P 2883 -u test@mysql#cluster_a -p ****** -D USERA --csv --table '*' -f /output

In this statement, -h, -P, -u, -p, and -D are connection options; --csv is a file format option; --table is a database object type option; and -f is a storage path option.

Basic options

Connection options

The OBDUMPER command needs to be connected to OceanBase Database to read and write data. You can specify the following options to connect to OceanBase Database.

Export types

Feature options

File formats

Compress and export

In DataArts Studio V4.3.0 and later, you can compress and export readable file formats such as CSV, CUT, POS, and SQL. You can configure the following command-line options.

• --compress

  A boolean value that specifies whether to compress the exported data.

• --compression-algo

  A string that specifies the compression algorithm. Valid values: zstd, zlib, gzip, and snappy. Default value: zstd.

• --compression-level

  An integer that specifies the compression level of the specified compression algorithm. The supported compression levels vary with the compression algorithm:

  • For zstd, the supported values range from 1 to 22. Default value: 3.

  • For zlib, the supported values range from -1 to 9. Default value: -1.

  • For gzip and snappy, you cannot specify the compression level.

Database object types

• --all

  Specifies to export the definitions of all database objects and the data of all tables. It is a collection of database object types such as --trigger and --view. The usage restrictions vary with the specific database object type.

  • When used with the --ddl option, it specifies to export the definitions of all database objects. For database object types such as --trigger that apply only to the Oracle compatible mode of OceanBase Database, if --all --ddl is specified in the MySQL compatible mode of OceanBase Database, triggers cannot be exported.

  • When used with any data format option such as --csv, --sql, or --cut, it specifies to export the data of all tables in the corresponding format. If you want to export the definitions of all database objects and the data of all tables, you can specify the --all or --ddl option in combination with any data format option.

  Notice

  The --all option is mutually exclusive with any database object option. You cannot specify both the --all option and any database object option at the same time. If you specify both the --all option and any database object option, the --all option takes precedence.

• --table-group 'table_group_name [,table_group_name...]' | --table-group '*'

  Specifies to export the definitions of table groups. Except for not supporting data export, the description is the same as that of the --table option.

• --table 'table_name [,table_name...]' | --table '*'

  Specifies to export the definitions or data of tables. When used with the --ddl option, it specifies to export only the definitions of tables. When used with any data format option such as --csv, --sql, or --cut, it specifies to export only the data of tables in the corresponding format. If multiple tables are to be exported, the table names are separated with commas (,). By default, the names of tables in an Oracle-compatible tenant of OceanBase Database are exported in uppercase, and the names of tables in a MySQL-compatible tenant of OceanBase Database are exported in lowercase. For example, in the Oracle compatible mode of OceanBase Database, both --table 'test' and --table 'TEST' specify the TEST table; in the MySQL compatible mode of OceanBase Database, both --table 'test' and --table 'TEST' specify the test table. If you want to distinguish the cases, enclose the table name in square brackets ([ ]). For example, --table '[test]' specifies the test table, and --table '[TEST]' specifies the TEST table. If the table name is specified as an asterisk (*), all table definitions or data are exported.

  Note

  • OBDUMPER does not support the export of internal tables or internal views of OceanBase Database.
  • OBDUMPER V4.1.0 and later support the export of temporary table definitions in the Oracle compatible mode of OceanBase Database.

• --view 'view_name [, view_name...]' | --view '* '

  Specifies to export the definitions of views. Except for not supporting data export, the description is the same as that of the --table option.

• --trigger 'trigger_name [, trigger_name...]' | --trigger '*'

  Specifies to export the definitions of triggers. Except for not supporting data export, the description is the same as that of the --table option. It applies only to the Oracle compatible mode of OceanBase Database.

• --obj-user 'user_name [, user_name...]' | --obj-user '*'

  Specifies to export the definitions of users. Except for not supporting data export, the description is the same as that of the --table option.

  Notice

  • In --public-cloud mode, the --obj-user option is not supported.

  • The privileges of a user in the Oracle compatible mode of OceanBase Database do not include BECOME USER, which is skipped by default.

  • User requirements: The login user must be an administrator or a user with the dba_users privilege in the Oracle compatible mode of OceanBase Database; or the login user must be an administrator or a user with the mysql.user table privilege in the MySQL compatible mode of OceanBase Database.

  • By default, the following users are ignored:

    • In the MySQL compatible mode of OceanBase Database: root, proxyro, standbyro, ORAAUDITOR, and __oceanbase_inner_drc_user.

    • In the Oracle compatible mode of OceanBase Database: SYS, proxyro, standbyro, PUBLIC, ORAAUDITOR, LBACSYS, and __OCEANBASE_INNER_DRC_USER.

• --role 'role_name [, role_name...]' | --role '*'

  Specifies to export the definitions of roles. Except for not supporting data export, the description is the same as that of the --table option.

  Notice

  In --public-cloud mode, the --role option is not supported.

  • User requirements: It applies only to the Oracle compatible mode of OceanBase Database. The login user must be an administrator or a user with the dba_users privilege.

  • By default, the following roles are ignored: CONNECT, RESOURCE, DBA, PUBLIC, and STANDBY_REPLICATION.

• --sequence 'sequence_name [, sequence_name...]' | --sequence '*'

  Specifies to export the definitions of sequences. Except for not supporting data export, the description is the same as that of the --table option.

  Notice

  OBDUMPER V4.0.0 and earlier versions apply only to the Oracle compatible mode of OceanBase Database. OBDUMPER V4.1.0 and later apply to both the MySQL compatible mode and the Oracle compatible mode of OceanBase Database.

  The optional --sequence-policy option can have the values restart and preserve, with preserve as the default.

  • By default or when preserve is specified, the start value is set to the current value of the sequence during export.

  • When restart is specified, the start value is set to the original definition of the sequence, and the sequence is exported as is.

• --synonym 'synonym_name [, synonym_name...]' | --synonym '*'

  Specifies to export the definitions of synonyms. Except for not supporting data export, the description is the same as that of the --table option. It applies only to the Oracle compatible mode of OceanBase Database.

• --type 'type_name [, type_name...]' | --type '*'

  Specifies to export the definitions of types. Except for not supporting data export, the description is the same as that of the --table option. It applies only to the Oracle compatible mode of OceanBase Database.

  Note

  Only OceanBase Database V2.2.77 and later in the Oracle compatible mode support the export of type definitions.

• --type-body 'typebody_name [, typebody_name...]' | --type-body '* '

  Specifies to export the definitions of type bodies. Except for not supporting data export, the description is the same as that of the --table option. It applies only to the Oracle compatible mode of OceanBase Database.

  Note

  This option must be used in combination with --type. The type body file is saved in the type file.

• --package 'package_name [, package_name...]' | --package '*'

  Specifies to export the definitions of packages. Except for not supporting data export, the description is the same as that of the --table option. It applies only to the Oracle compatible mode of OceanBase Database.

• --package-body 'packagebody_name [, packagebody_name...]' | --package-body '*'

  Specifies to export the definitions of package bodies. Except for not supporting data export, the description is the same as that of the --table option. It applies only to the Oracle compatible mode of OceanBase Database.

• --function 'function_name [, function_name...]' | --function '*'

  Specifies to export the definitions of functions. Except for not supporting data export, the description is the same as that of the --table option.

  Note

  Function definitions can be exported in all versions of OceanBase Database in the Oracle compatible mode. Function definitions can be exported in OceanBase Database V2.2.30 and later in the MySQL compatible mode.

• --procedure 'procedure_name [, procedure_name...]' | --procedure '*'

  Specifies to export the definitions of stored procedures. Except for not supporting data export, the description is the same as that of the --table option.

  Note

  Stored procedure definitions can be exported in all versions of OceanBase Database in the Oracle compatible mode. Stored procedure definitions can be exported in OceanBase Database V2.2.30 and later in the MySQL compatible mode.

Storage path

• -f 'file_path', --file-path= 'file_path'

  Specifies the absolute path on the local disk where the data file is stored.

  Note

  When you use OBDUMPER V4.2.7 or later, you can specify a specific file name for -f when you export a single file.

  • If you specify --query-sql, the default file name CUSTOM_SQL will be replaced.
  • The log directory will be generated in the parent directory of the path specified by -f.

  OBDUMPER allows you to export database object definitions and table data to a local disk, Alibaba Cloud OSS, Amazon S3, Tencent Cloud Object Storage (COS), and Huawei Cloud Object Storage Service (OBS). The syntax is as follows:

  [scheme://host]path[?parameters]
  
  parameters: key[=value]&...
  

  Component	Description
  scheme	The supported storage type. Valid values: OSS, S3, COS, and OBS. If the specified scheme is not OSS, S3, COS, or OBS, an error will be returned.
  host	The name of the storage space. When you export data to OSS, S3, COS, or OBS, host represents the bucket name. For more information, see OSS bucket.
  path	The resource path of the storage space. The path must start with /.
  parameters	The parameters required for the request. parameters can be a single key or a key-value pair.

  The supported parameters are as follows:

  Parameter	Whether a value is required	Description	Supported storage types	The version of the data export tool that first supports this parameter
  endpoint	Yes	The endpoint of the region where the host is located. The domain name endpoint for accessing OSS/S3/COS/OBS. Example: oss://ssmp-xxxx-xxxx/test?endpoint=oss-cn-shenzhen-internal.aliyuncs.com.	OSS/S3/COS/OBS	OSS: V4.2.0 S3: V4.2.5 COS/OBS: V4.3.0
  region	Yes	The region where the endpoint is located.	OSS/S3/COS/OBS	OSS/S3: V4.2.0 COS/OBS: V4.3.0
  storage-class	Yes	The Amazon S3 storage class.	S3	4.2.0
  access-key	Yes	The access account for the storage.	OSS/S3/COS/OBS	OSS/S3: V4.2.0 COS/OBS: V4.3.0
  secret-key	Yes	The access key for the storage.	OSS/S3/COS/OBS	OSS/S3: V4.2.0 COS/OBS: V4.3.0

  Here are some examples:

  • Export data to a local disk

    -f '/home/admin/foo/bar' 
    

  • Export data to S3

    -f 's3://bucket/path?region={region}&access-key={accessKey}&secret-key={secretKey}'
    

  • Export data to OSS

    -f 'oss://mybucket/foo/bar?endpoint=myendpoint&access-key=myak&secret-key=mysk' 
    

  • Export data to COS

    -f 'cos://mybucket/foo?region=ap-shanghai&access-key=myak&secret-key=mysk'
    -f 'cos://mybucket/foo?endpoint=yourendpoint&access-key=myak&secret-key=mysk'
    

  • Export data to OBS

    -f 'obs://mybucket/foo?region=cn-north-1&access-key=myak&secret-key=mysk'
    -f 'obs://mybucket/foo?endpoint=yourendpoint&access-key=myak&secret-key=mysk'
    

• --ctl-path 'control_path'

  Specifies the absolute path on the local disk where the control file is stored. You can configure built-in processing functions in the control file. Before data is exported, the system preprocesses the data based on the configured functions. For example, the system can convert the case of characters and check for empty values. For more information about control files, see Data processing. When you specify this option on the command line, enclose the parameter value in single quotation marks. For example: --ctl-path '/home/controls/'.

• --log-path 'log_path'

  Specifies the output directory for OBDUMPER running logs. If you do not specify this option on the command line, OBDUMPER running logs are output to the directory specified by the -f option. In most cases, you do not need to use redirection to output logs.

• --no-nested-dir

  Specifies to export a flat directory structure. All files are exported to the directory specified by -f without generating any subdirectories.

• By default, OBDUMPER uses the multipart upload method to export data to an object storage system and uses the local file system as the temporary directory (which can be changed by using the --tmp-path option) to store file fragments. You can modify the following parameters in the OBDUMPER startup script to adapt to the actual data export environment.

  • upload.buffer.type

    Specifies the buffer type. Valid values: disk and bytebuffer. disk is the default value. It uses disks to store file fragments and is limited by the maximum available disk space. bytebuffer uses memory to store file fragments, which offers better performance but consumes a large amount of JVM heap memory.

  • upload.buffer.size

    Specifies the size of each file fragment in bytes. The default value is 64 MB.

  • upload.active.blocks

    Specifies the maximum number of file fragments that can exist simultaneously for each write thread (which may be in the process of uploading or waiting in the queue for upload). The default value is 2. When the number of file fragments exceeds this value, the program will block until one of the file fragments is uploaded and removed from the waiting queue.

    The --thread option limits the maximum number of write threads. You can use the formula thread * active.blocks * buffer.size to estimate the space that the buffer may occupy during program operation.

Other options

• -H, --help

  Displays the help information for the command-line tool.

• -V, --version

  Displays the version number of the current release.

Advanced options

Feature options

Timestamp formats

• --flashback-timestamp 'timestamp_string'

  Specifies the flashback point after which data is exported. This option can be used only with any one of the data format options and cannot be used with the --query-sql option. This option applies only to the Oracle compatible mode of OceanBase Database.

• --nls-date-format 'date-format-string'

  Specifies the nls_date_format session variable in the Oracle compatible mode of OceanBase Database. This option does not indicate that data of the DATE type is exported in the specified format. Default value: YYYY-MM-DD HH24:MI:SS.

• --nls-timestamp-format 'timestamp-format-string'

  Specifies the nls_timestamp_format session variable in the Oracle compatible mode of OceanBase Database. This option does not indicate that data of the TIMESTAMP type is exported in the specified format. Default value: YYYY-MM-DD HH24:MI:SS:FF9.

• --nls-timestamp-tz-format 'timestamp-tz-format-string'

  Specifies the nls_timestamp_tz_format session variable in the Oracle compatible mode of OceanBase Database. This option does not indicate that data of the TIMESTAMP WITH TIME ZONE type is exported in the specified format. Default value: YYYY-MM-DD HH24:MI:SS:FF9 TZR.

• --date-value-format

  Specifies the export format for the DATE type. In the MySQL compatible mode of OceanBase Database, the default format for the DATE type is yyyy-MM-dd. In the Oracle compatible mode of OceanBase Database, the default format for the DATE type is yyyy-MM-dd HH:mm:ss.

  Note

  • This option can be used only with the --csv or --cut option.
  • In the MySQL compatible mode of OceanBase Database, if the DATE value is zero, this option does not support setting the format for the DATE type.

• --time-value-format

  Specifies the export format for the TIME type. In the MySQL compatible mode of OceanBase Database, the default format for the TIME type is HH:mm:ss, and the precision is the same as that in the table definition.

  Note

  • This option can be used only with the --csv or --cut option.
  • In the MySQL compatible mode of OceanBase Database, if the TIME value is zero, this option does not support setting the format for the TIME type.

• --datetime-value-format

  Specifies the export format for the DATETIME type. In the MySQL compatible mode of OceanBase Database, the default format for the DATETIME type is yyyy-MM-dd HH:mm:ss, and the precision is the same as that in the table definition.

  Note

  • This option can be used only with the --csv or --cut option.
  • In the MySQL compatible mode of OceanBase Database, if the DATETIME value is zero, this option does not support setting the format for the DATETIME type.

• --timestamp-value-format

  Specifies the export format for the TIMESTAMP type. In the MySQL compatible mode of OceanBase Database, the default format for the TIMESTAMP type is yyyy-MM-dd HH:mm:ss.SSSSSS, and the precision is the same as that in the table definition.

  Note

  • This option can be used only with the --csv or --cut option.
  • In the MySQL compatible mode of OceanBase Database, if the TIMESTAMP value is zero, this option does not support setting the format for the TIMESTAMP type.

• --timestamp-tz-value-format

  Specifies the export format for the TIMESTAMP WITH TIME ZONE type. In the Oracle compatible mode of OceanBase Database, the default format for the TIMESTAMP WITH TIME ZONE type is yyyy-MM-dd HH:mm:ss.SSSSSS, and the precision is the same as that in the table definition.

  Note

  This option can be used only with the --csv or --cut option.

• --timestamp-ltz-value-format

  Specifies the export format for the TIMESTAMP WITH LOCAL TIME ZONE type. In the Oracle compatible mode of OceanBase Database, the default format for the TIMESTAMP WITH LOCAL TIME ZONE type is yyyy-MM-dd HH:mm:ss, and the precision is the same as that in the table definition.

  Note

  This option can be used only with the --csv or --cut option.

• --preserve-zero-datetime

  Specifies to retain the original format of zero values of date and time types during export. If this option is specified, the NULL values of non-nullable date and time columns are exported as 0, and the NULL values of nullable columns are still exported as NULL. This option applies to the DATE, DATETIME, and TIMESTAMP types in the MySQL compatible mode.

Blocklist and allowlist filtering

• Table-level filtering

  • --exclude-table 'table_name [, table_name...]'

    Specifies the tables to be excluded when exporting table definitions or data. The table name supports fuzzy matching.

    Example: --exclude-table 'test1,test*,*test,te*st'

    The preceding option specifies the following tables to be excluded:

    • test1

    • All tables whose names start with test

    • All tables whose names end with test

    • All tables whose names start with te and end with st

  • --exclude-data-types 'datatype [, datatype...]'

    Specifies the data types to be excluded when exporting data.

  • --add-extra-message

    Specifies whether to include additional information in the exported table definition. For example, if you specify the --add-extra-message option to export a table definition, the program will export the name of the table group to which each table belongs. By default, OBDUMPER does not export additional information in the table definition.

    Notice

    If you specify the --add-extra-message option to export a table definition, the program will export the name of the table group to which each table belongs. This option depends on the privileges in the sys tenant. If OBDUMPER does not have the privileges in the sys tenant, do not specify this option.

  • --retain-empty-files

    Specifies whether to generate empty files when exporting data in specific scenarios. If you specify the --partition option to export data in a specific partition or the --where option to export data based on a query condition, and you also specify the --retain-empty-file option, an empty file will be generated if the partition is empty or the query result set is empty.

• Column-level filtering

  • --include-column-names 'column_name [, column_name...]'

    Specifies the columns to export based on the specified column names.

  • --exclude-column-names 'column_name [, column_name...]'

    Specifies the columns to be excluded when exporting data. The column name does not support fuzzy matching.

    Notice

    • The specified column names must be in the same case as the column names in the table definition.
    • The control file cannot be used together with the --exclude-column-names option. The control file includes the functionality of the --exclude-column-names option.

  • --where 'where_condition_string'

    Specifies the data to be exported based on the specified condition. This option can be used only with any one of the data format options and cannot be used with the --query-sql option.

    If you specify the --where option to export data based on a query condition and you also specify the --retain-empty-file option, an empty file will be generated if the query result set is empty.

  • --partition 'partition_name [, partition_name...]'

    Specifies the partition to export data from. The parameter value is the partition name, and multiple partition names are separated with commas. This option can be used only with any one of the data format options and cannot be used with the --query-sql option.

    Notice

    • When you specify a partition to export data from, for a subpartitioned table, you must specify the subpartition name, and you cannot export data based on the partition name. For a template subpartition, the partition name is the partition name plus s plus the subpartition name.
    • If you specify the --partition option to export data from a partition, you must specify the subpartition name for a composite partitioned table. OBDUMPER cannot export data from a partition. If the specified partition name does not exist, OBDUMPER will return an error.
    • If you specify the --partition option to export data from a partition and you also specify the --retain-empty-file option, an empty file will be generated if the partition is empty.

  • --query-sql

    • Directly specify the query statement --query-sql '<select_statement>'. For example, --query-sql 'select c1,c2 from test where c1 is not null'.

      Specifies whether to export the result data of a custom query statement. This option cannot be used with the --partition or --where option. You must ensure the correctness and query performance of the custom query statement. If you export the result set of a large query statement, the waiting time for a response from the database may be long. If you need to preprocess the data using a control file, you must use the --table and --ctl-path options. The table name specified by the --table option must be in the same case as the file name specified by the --ctl-path option. If no preprocessing is required, you can specify any table name for the --table option.

    • Specify the file that stores the query statement --query-sql 'file://xxxx'. For example, --query-sql 'file:///home/admin/t1.sql'.

      OBDUMPER identifies the file:// protocol header and reads the SQL statements from the file. This option supports only one very long SQL statement and does not support multiple SQL statements in one file.

  • --exclude-virtual-columns

    Specifies whether to exclude data of generated columns (by default, data of generated columns is exported).

  • --enable-hidden-pk

    Specifies to use the hidden primary key __pk_increment for tables without a primary key to improve the export speed. In OceanBase Database of a version earlier than V4.0.0, you must use a special user to export data when you specify this option. Example:

    # In MySQL compatible mode of OceanBase Database, create a special user and grant privileges to the user.
    create user '__oceanbase_inner_drc_user'@'%' IDENTIFIED BY 'u*******';
    grant ALL on *.* to '__oceanbase_inner_drc_user' WITH GRANT OPTION;
    
    # In Oracle compatible mode of OceanBase Database, create a special user and grant privileges to the user.
    create user '__OCEANBASE_INNER_DRC_USER'@'%' IDENTIFIED BY u*******;
    grant ALL to '__OCEANBASE_INNER_DRC_USER';
    

    Notice

    If you use OceanBase Database V3.x's partitioned tables, we recommend that you set LOCAL indexes. The syntax is: create index "your index" on `your table` ("__pk_increment") local;

  • --fetch-size 'int_num'

    Specifies the number of rows to read from the database cursor in Oracle compatible mode of OceanBase Database. Default value: 1000. For more information, see OceanBase FetchSize.

    Note

    You must install the OceanBase JDBC driver.

Error handling

• --retry

  Specifies to resume the export task from the last failed position.

  Notice

  The dump.ckpt file is a save point file generated during the operation of the tool and is stored in the directory specified by -f. If the dump.ckpt file does not exist, this option cannot be used.

• --weak-read

  Specifies to export data from the standby replica. For more information about weak-consistency reads, see Weak-consistency read.

• --max-file-size int_num

  Specifies the maximum amount of data that a process can export. The export stops when the amount of data to be exported exceeds the value specified by this option.

• --skip-check-dir

  Specifies to skip checking whether the directory for the exported data is empty. If the directory is not empty, the program stops exporting data.

  Note

  • If this option is not specified, OBDUMPER checks whether the directory is empty. If the directory is not empty, OBDUMPER reports an error and exits.
  • If this option is specified, OBDUMPER skips checking whether the directory is empty. However, the exported files may overwrite the data of the files with the same name in the directory.

• --remove-newline

  Specifies to forcibly delete carriage returns or line breaks from the data during the export. For example, ***\r***, ***\n***, and ***\r\n***. This option only applies to data read into the memory and does not directly modify the data in the source table. This option can be used only with the --cut option.

  Notice

  If the data in the source table contains carriage returns or line breaks, the data exported by specifying this option is inconsistent with the data in the source table. Before using this option, confirm that deleting \r, \n, and \r\n characters will not affect your business. If you do not need to delete carriage returns or line breaks from the data, do not specify this option on the command line to avoid business data inconsistency.

• --snapshot

  Specifies to export historical version data. This option can be used only with any one of the data format options. The purpose of exporting historical version data is to ensure global consistency of the exported data. If this option is not specified on the command line, the exported real-time data in the memory may not be a global consistent data snapshot.

Performance options

• --page-size int_num

  Specifies the size of a task page, that is, the number of rows to be queried at a time. The default value is 1,000,000. For example, you can specify this option as 1,000,000 to query 1 million rows at a time. This option is supported in OBDUMPER V4.0.0 and later.

• --thread int_num

  Specifies the number of concurrent threads. This option directly corresponds to the number of export threads. The default value is CPU × 2. If the number of CPU cores exceeds 16, the maximum number of threads is 32. If you export definitions of multiple database objects, we recommend that you do not set the value of this option to exceed 4. Too many concurrent threads may cause the tool to fail to access system tables in the sys tenant and cause a timeout error during export.

• --block-size

  Specifies the threshold for splitting files. It applies to the LONG and STRING data types. If the size of the exported data file exceeds the threshold, other logical subfiles are generated in sequence. If you specify this option, you do not need to explicitly specify the unit. The default unit is MB. The default value is 0, which indicates an unlimited size (only one file is generated for an object). This option does not take effect for the ORC and Parquet formats.

  OBDUMPER V4.1.0 and later support splitting files based on the number of rows. The value of --block-size is in the unit of MB or ROW. For example, --block-size 256ROW specifies that the size of each file does not exceed 256 rows. --block-size 1024 or --block-size 1024MB specifies that the size of each file does not exceed 1024 MB. The 1024M and 1 GB formats are not supported.

  Notice

  If you use --block-size, you must specify path address for -f.

• --parallel-macro int_num

  Specifies the number of macroblocks processed by one thread. The default value is 8.

• --mem

  Specifies the memory size of the JVM. This parameter is supported in OBDUMPER V4.3.2 and later. The supported units are K, M, G, and T. The default value is 4G.

Other options

• --session-config

  Specifies the connection configuration file. A default configuration file named session.config.json is provided in the configuration file directory: <tool root directory>/conf/. This configuration file takes effect without any configuration. We recommend that you specify this option only when you need to load multiple connection configurations by using the same configuration file directory.

• --retain-schema

  Specifies to retain the schema information of the exported tables and synonyms. By default, the exported DDL statements do not contain schema information but only table names. You can specify the --retain-schema option to retain the schema.table name.

Options