This document describes the data migration tool mxshift.
The mxshift tool currently supports the following features:
WHERE clause.Note!
All features of themxshifttool require execution under superuser privileges.
Without superuser privileges, the following limitations apply: data compression is not supported; incremental migration is not supported; fetch mode is not supported.
Additionally, during migration, you must manually add the target host into thepg_hba.conffile on all source nodes.
The complete template file is named config.toml. This template can be obtained by running mxshift --config.
Below are example templates for different use cases. Use them as references and modify the configuration using the vim config.toml command according to your environment.
[database]
[database.source]
## Name of database
db-database= "testdb"
## Hostname of database master
db-host="sdw3"
## password of database
db-password="xxxx"
## Port of database master
db-port=54322
## user name of database
db-user="gpadmin"
## Version of database(Please use the result of 'SELECT version();' as value). Required only when
## 1. Source database is un-reachable, and 'ddl.only-ddl' is enabled and 'ddl.mode' is 'input'
## 2. Target database is un-reachable, and 'ddl.mode' is 'output'
# db-version="PostgreSQL 12 (MatrixDB 5.2.0-enterprise) (Greenplum Database 7.0.0+dev.17410.gedbdb5ef84 build dev) on arm-apple-darwin21.5.0, compiled by Apple clang version 13.0.0 (clang-1300.0.27.3), 64-bit compiled on Jun 5 2023 15:45:24"
## The installation directory of database
install-dir="/usr/local/greenplum-db-6.7.1"
[[database.source.hostname-to-ip]]
## The content within <> should be replaced with actual information and <> should be removed
node-hostname="<mdw>"
node-ip="<127.0.0.1>"
[[database.source.hostname-to-ip]]
node-hostname="<sdw1>"
node-ip="<127.0.0.2>"
[[database.source.hostname-to-ip]]
node-hostname="<sdw2>"
node-ip="<127.0.0.3>"
[database.target]
## Name of database
db-database="destdb"
## Hostname of database master
db-host="172.16.100.32"
## password of database
db-password="yyyy"
## Port of database master
db-port=5432
## user name of database
db-user="mxadmin"
## Version of database(Please use the result of 'SELECT version();' as value). Required only when
## 1. Source database is un-reachable, and 'ddl.only-ddl' is enabled and 'ddl.mode' is 'input'
## 2. Target database is un-reachable, and 'ddl.mode' is 'output' */
# db-version="PostgreSQL 12 (MatrixDB 5.2.0-enterprise) (Greenplum Database 7.0.0+dev.17410.gedbdb5ef84 build dev) on arm-apple-darwin21.5.0, compiled by Apple clang version 13.0.0 (clang-1300.0.27.3), 64-bit compiled on Jun 5 2023 15:45:24"
[scope]
## Whether to disable data incremental migration, by default, it is true.
# disable-data-increment=true
disable-connector=false
## The compress method for transferring data, methods restricted to 0/gzip/lz4/zstd
compress-method="lz4"
## mode for transferring data from source to target database, and value restricted to normal/dryrun/fetch/motion.
##dryrun for only executing ddl, not transferring data
##fetch for fetching data from source and abandon
##motion for fetching data from source, redistributing and finally abandon
mode="normal"
## Sql for select segment information from source database
# select-source-segment-sql="SELECT dbid, content, port, hostname FROM gp_segment_configuration WHERE status = 'u' AND role = 'p' ORDER BY CONTENT;"
## Sql for select segment information from target database
# select-target-segment-sql="SELECT dbid, content, port, hostname FROM gp_segment_configuration WHERE status = 'u' AND role = 'p' ORDER BY CONTENT;"
[[scope.table-list]]
schema="test_schema_1"
name="table_001"
[[scope.table-list]]
schema="test_schema_2"
name="table_002"
[[scope.exclude-table-list]]
schema="test_schema_3"
name="table_003"
schema-list=["test_schema_1", "test_schema_2"]
exclude-schema-list=["test_schema_5", "test_schema_8"]
[log]
## The log level, value restricted to: debug/verbose/info.
log-level="info"
## Print log without color.
# no-color=false
[controller]
## By default, transfer work will start from the largest table. If set 'bothway' it will start from both the largest and the smallest table
both-way=true
## The number of table transferred at the same time
concurrency=3
[transfer]
## Verity the number of record of every table
verify=true
with-index=true
## Whether to disable transfer Data, by default, it is false.
# disabled-data-transfer=false
## Table with size under this threshold are categorized as "small",
## transfer between masters instead of segments to avoid creating external table.
# small-table-mb=32
[ddl]
enabled=true
# file-path="/tmp/mxshift.sql"
# mode="output"
only-ddl=false
## During the DDL transfer, whether to skip the transfer of resource queue or group, by default, it is true.
# skip-resource-queue-and-group=true
## During the DDL transfer, whether to skip the transfer of tablespace, by default, it is true.
# skip-table-space=true
[[ddl.replace]]
## Only applicable for the case of migration from Greenplum to YMatrix
category="role"
[[ddl.replace.pairs]]
old="gpadmin"
new="mxadmin"
## Whether to disable ddl incremental migration, by default, it is true.
# disable-ddl-increment=true
## DDL transfer will stop and exit when executing sql encounter errors, unless the type of DDL is set to 'ignore error'.Types of DDL are:
## "all","collation","default acl","extension","external table","function","index","language",
## "namespace","operator","resource","role","table","tablespace","type","view"
# ignore-error=[]
[verify]
## Whether to enable data verify, by default, it is false.
# enabled=false
## mode for verifying data consistency between source and target database,
## and value restricted to simple-count/column-count/length-sum/hash-bit-bloom.
## 'simple-count' for counting number of rows
## 'column-count' for counting not-null value of a certain column
## 'length-sum' for summing the length of some columns(e.g. column of type text, xml, json, varchar)
## 'hash-bit-bloom' for calculating the hash for one or more columns, and compare it's binary content
## (except for column of floating-point type, the result of witch can be affected by software/hardware)
# mode="simple-count"
## Columns used in verification, will randomly select columns if not set
# columns=[]
## Maximum number of randomly selected columns used in verification
# max-column-count=3
# [[verify.table-list]]
# schema="test_schema_1"
# name="table_001"
# [[verify.exclude-table-list]]
# schema="test_schema_3"
# name="table_003"
# verify.schema-list=["test_schema_1"]
# verify.exclude-schema-list=["test_schema_5"]
# [[verify.override]]
# mode="length-sum"
# max-column-count=3
# columns=[]
# [[verify.override.table-list]]
# schema="test_schema_3"
# name="table_003"
# verify.override.schema-list=[]
# [[verify.override]]
# mode="column-count"
# max-column-count=2
# columns=[]
# [[verify.override.table-list]]
# schema="test_schema_1"
# name="table_001"
# verify.override.schema-list=[]After preparing the TOML configuration file, run the following command to start full migration:
$ mxshift -c config_path_full.toml[database]
[database.source]
## Name of database
db-database= "testdb"
## Hostname of database master
db-host="sdw3"
## password of database
db-password="xxxx"
## Port of database master
db-port=54322
## user name of database
db-user="gpadmin"
## Version of database(Please use the result of 'SELECT version();' as value). Required only when
## 1. Source database is un-reachable, and 'ddl.only-ddl' is enabled and 'ddl.mode' is 'input'
## 2. Target database is un-reachable, and 'ddl.mode' is 'output' */
# db-version="PostgreSQL 12 (MatrixDB 5.2.0-enterprise) (Greenplum Database 7.0.0+dev.17410.gedbdb5ef84 build dev) on arm-apple-darwin21.5.0, compiled by Apple clang version 13.0.0 (clang-1300.0.27.3), 64-bit compiled on Jun 5 2023 15:45:24"
## The installation directory of database
install-dir="/usr/local/greenplum-db-6.7.1"
[[database.source.hostname-to-ip]]
## The content within <> should be replaced with actual information and <> should be removed
node-hostname="<mdw>"
node-ip="<127.0.0.1>"
[[database.source.hostname-to-ip]]
node-hostname="<sdw1>"
node-ip="<127.0.0.2>"
[[database.source.hostname-to-ip]]
node-hostname="<sdw2>"
node-ip="<127.0.0.3>"
[database.target]
## Name of database
db-database="destdb"
## Hostname of database master
db-host="172.16.100.32"
## password of database
db-password="yyyy"
## Port of database master
db-port=5432
## user name of database
db-user="mxadmin"
## Version of database(Please use the result of 'SELECT version();' as value). Required only when
## 1. Source database is un-reachable, and 'ddl.only-ddl' is enabled and 'ddl.mode' is 'input'
## 2. Target database is un-reachable, and 'ddl.mode' is 'output' */
# db-version="PostgreSQL 12 (MatrixDB 5.2.0-enterprise) (Greenplum Database 7.0.0+dev.17410.gedbdb5ef84 build dev) on arm-apple-darwin21.5.0, compiled by Apple clang version 13.0.0 (clang-1300.0.27.3), 64-bit compiled on Jun 5 2023 15:45:24"
[scope]
disable-connector=false
## The compress method for transferring data, methods restricted to 0/gzip/lz4/zstd
compress-method="lz4"
## mode for transferring data from source to target database, and value restricted to normal/dryrun/fetch/motion.
##dryrun for only executing ddl, not transferring data
##fetch for fetching data from source and abandon
##motion for fetching data from source, redistributing and finally abandon
mode="normal"
## Sql for select segment information from source database
# select-source-segment-sql="SELECT dbid, content, port, hostname FROM gp_segment_configuration WHERE status = 'u' AND role = 'p' ORDER BY CONTENT;"
## Sql for select segment information from target database
# select-target-segment-sql="SELECT dbid, content, port, hostname FROM gp_segment_configuration WHERE status = 'u' AND role = 'p' ORDER BY CONTENT;"
## Whether to disable data incremental migration, by default, it is true.
disable-data-increment=false
[[scope.table-list]]
schema="test_schema_1"
name="table_001"
[[scope.table-list]]
schema="test_schema_2"
name="table_002"
[[scope.exclude-table-list]]
schema="test_schema_3"
name="table_003"
schema-list=["test_schema_1", "test_schema_2"]
exclude-schema-list=["test_schema_5", "test_schema_8"]
[log]
## The log level, value restricted to: debug/verbose/info.
log-level="info"
## Print log without color.
# no-color=false
[controller]
## By default, transfer work will start from the largest table. If set 'bothway' it will start from both the largest and the smallest table
both-way=true
## The number of table transferred at the same time
concurrency=3
[transfer]
## Verity the number of record of every table
verify=true
with-index=true
## Whether to disable transfer Data, by default, it is false.
# disabled-data-transfer=false
## Table with size under this threshold are categorized as "small",
## transfer between masters instead of segments to avoid creating external table.
# small-table-mb=32
[ddl]
enabled=true
# file-path="/tmp/mxshift.sql"
# mode="output"
only-ddl=false
## During the DDL transfer, whether to skip the transfer of resource queue or group, by default, it is true.
# skip-resource-queue-and-group=true
## During the DDL transfer, whether to skip the transfer of tablespace, by default, it is true.
# skip-table-space=true
[[ddl.replace]]
## Only applicable for the case of migration from Greenplum to YMatrix
category="role"
[[ddl.replace.pairs]]
old="gpadmin"
new="mxadmin"
## Whether to disable ddl incremental migration, by default, it is true.
disable-ddl-increment=false
## DDL transfer will stop and exit when executing sql encounter errors, unless the type of DDL is set to 'ignore error'.Types of DDL are:
## "all","collation","default acl","extension","external table","function","index","language",
## "namespace","operator","resource","role","table","tablespace","type","view"
# ignore-error=[]
[verify]
## Whether to enable data verify, by default, it is false.
# enabled=false
## mode for verifying data consistency between source and target database,
## and value restricted to simple-count/column-count/length-sum/hash-bit-bloom.
## 'simple-count' for counting number of rows
## 'column-count' for counting not-null value of a certain column
## 'length-sum' for summing the length of some columns(e.g. column of type text, xml, json, varchar)
## 'hash-bit-bloom' for calculating the hash for one or more columns, and compare it's binary content
## (except for column of floating-point type, the result of witch can be affected by software/hardware)
# mode="simple-count"
## Columns used in verification, will randomly select columns if not set
# columns=[]
##
--- SPLIT ---
Maximum number of randomly selected columns used in verification
# max-column-count=3
# [[verify.table-list]]
# schema="test_schema_1"
# name="table_001"
# [[verify.exclude-table-list]]
# schema="test_schema_3"
# name="table_003"
# verify.schema-list=["test_schema_1"]
# verify.exclude-schema-list=["test_schema_5"]
# [[verify.override]]
# mode="length-sum"
# max-column-count=3
# columns=[]
# [[verify.override.table-list]]
# schema="test_schema_3"
# name="table_003"
# verify.override.schema-list=[]
# [[verify.override]]
# mode="column-count"
# max-column-count=2
# columns=[]
# [[verify.override.table-list]]
# schema="test_schema_1"
# name="table_001"
# verify.override.schema-list=[] After preparing the TOML file, run the following command to start mxshift for incremental migration.
$ mxshift -c config_path_incremental.toml Use the WHERE condition to migrate only data that meets specific criteria or exclude expired data from migration:
[database]
[database.source]
## Name of database
db-database= "testdb"
## Hostname of database master
db-host="sdw3"
## password of database
db-password="xxxx"
## Port of database master
db-port=54322
## user name of database
db-user="gpadmin"
## The installation directory of database
install-dir="/usr/local/greenplum-db-6.7.1"
[database.target]
## Name of database
db-database="destdb"
## Hostname of database master
db-host="172.16.100.32"
## password of database
db-password="yyyy"
## Port of database master
db-port=5432
## user name of database
db-user="mxadmin"
[scope]
## The compress method for transferring data, methods restricted to 0/gzip/lz4/zstd
compress-method="lz4"
## mode for transferring data from source to target database, and value restricted to normal/dryrun/fetch/motion.
##dryrun for only executing ddl, not transferring data
##fetch for fetching data from source and abandon
##motion for fetching data from source, redistributing and finally abandon
mode="normal"
## Sql for select segment information from source database
# select-source-segment-sql="SELECT dbid, content, port, hostname FROM gp_segment_configuration WHERE status = 'u' AND role = 'p' ORDER BY CONTENT;"
## Sql for select segment information from target database
# select-target-segment-sql="SELECT dbid, content, port, hostname FROM gp_segment_configuration WHERE status = 'u' AND role = 'p' ORDER BY CONTENT;"
[[scope.table-list]]
schema=......
name=......
[[scope.table-list]]
......
[[scope.exclude-table-list]]
......
schema-list=["test_schema_1", "test_schema_2"]
exclude-schema-list=["test_schema_5", "test_schema_8"]
disable-connector=false
[log]
## The log level, value restricted to: debug/verbose/info.
log-level="info"
## Print log without color.
# no-color=false
[controller]
## By default, transfer work will start from the largest table. If set 'bothway' it will start from both the largest and the smallest table
both-way=true
## The number of table transferred at the same time
concurrency=3
[transfer]
## Verity the number of record of every table
verify=true
## Table with size under this threshold are categorized as "small",
## transfer between masters instead of segments to avoid creating external table.
# small-table-mb=32
[transfer.table-data-where-sql]
enabled=true
global="txdate >= '2022-10-01' AND batchnum >= 100000000"
[[transfer.table-data-where-sql.override]]
where="abc > 10"
[transfer.table-data-where-sql.override.table]
schema="test_schema_1"
name="table_001"
[[transfer.table-data-where-sql.override]]
where="tag != 'aabbcc' AND ts > '2022-01-01'"
[transfer.table-data-where-sql.override.table]
schema="test_schema_2"
name="another_table"
[verify]
## Whether to enable data verify, by default, it is false.
# enabled=false
## mode for verifying data consistency between source and target database,
## and value restricted to simple-count/column-count/length-sum/hash-bit-bloom.
## 'simple-count' for counting number of rows
## 'column-count' for counting not-null value of a certain column
## 'length-sum' for summing the length of some columns(e.g. column of type text, xml, json, varchar)
## 'hash-bit-bloom' for calculating the hash for one or more columns, and compare it's binary content
## (except for column of floating-point type, the result of witch can be affected by software/hardware)
# mode="simple-count"
## Columns used in verification, will randomly select columns if not set
# columns=[]
## Maximum number of randomly selected columns used in verification
# max-column-count=3
# [[verify.table-list]]
# schema="test_schema_1"
# name="table_001"
# [[verify.exclude-table-list]]
# schema="test_schema_3"
# name="table_003"
# verify.schema-list=["test_schema_1"]
# verify.exclude-schema-list=["test_schema_5"]
# [[verify.override]]
# mode="length-sum"
# max-column-count=3
# columns=[]
# [[verify.override.table-list]]
# schema="test_schema_3"
# name="table_003"
# verify.override.schema-list=[]
# [[verify.override]]
# mode="column-count"
# max-column-count=2
# columns=[]
# [[verify.override.table-list]]
# schema="test_schema_1"
# name="table_001"
# verify.override.schema-list=[] After preparing the TOML file, run the following command to start mxshift for conditional migration.
$ mxshift -c config_path_conditional.toml When migrating an entire database or all replicated tables under a specific schema, no additional configuration is required in config_path.toml. mxshift automatically identifies replicated tables and applies the appropriate migration strategy to prevent data duplication. You only need to configure scope.table-list, specifically setting schema and name.
[[scope.table-list]]
schema=“public1”
name=“table_replicated1”
[[scope.table-list]]
schema=“public2”
name=“table_replicated2” After preparing the TOML file, run the following command to start mxshift for replicating table migration.
$ mxshift -c config_path_replicated.toml Note!
For a detailed explanation of data migration strategies and complete steps, refer to Data Migration.
For data migration, mxshift first queries the catalog to obtain metadata of the tables to be migrated, then proceeds with the data transfer.
As database usage increases, catalog bloat may lead to longer query times. To speed up debugging and reduce service downtime during migration, mxshift provides command-line options to export table metadata and reuse it in subsequent migrations:
## Export table metadata to mxshift_meta_file and exit
$ mxshift -c <migration_config_file> --write-table-meta-file mxshift_meta_file
## Import table metadata from mxshift_meta_file and proceed with data migration
$ mxshift -c <migration_config_file> --read-table-meta-file mxshift_meta_file Note!
Exported table metadata should not be used long-term. Regenerate the metadata whenever the set of tables to migrate changes or when table definitions are modified.
Configure the following in the mxshift configuration file:
[ddl]
enabled=true
file-path="/tmp/mxshift.sql"
mode="output" -- DO NOT EDIT.. exec, output, and input. Their meanings are: exec: Default. Execute DDL directly on the target database. output: Output DDL to the specified file. After export, mxshift exits without performing data migration. input: Read DDL from the specified file and apply it. If the target database is unreachable under output, configure database.target.db-version as shown below to ensure successful DDL export:
[database]
[database.target]
...
## Version of database (Use output of 'SELECT version();'). Required only when
## 1. Source database is unreachable, 'ddl.only-ddl' is enabled, and 'ddl.mode' is 'input'
## 2. Target database is unreachable, and 'ddl.mode' is 'output'
db-version="PostgreSQL 12 (MatrixDB 5.2.0-enterprise) (Greenplum Database 7.0.0+dev.17410.gedbdb5ef84 build dev) on arm-apple-darwin21.5.0, compiled by Apple clang version 13.0.0 (clang-1300.0.27.3), 64-bit compiled on Jul 5 2022 15:45:24" If the source database is unreachable under input, configure database.source.db-version and ddl.only-ddl as shown below to ensure successful import:
[database]
[database.target]
## Version of database (Use output of 'SELECT version();'). Required only when
## 1. Source database is unreachable, 'ddl.only-ddl' is enabled, and 'ddl.mode' is 'input'
## 2. Target database is unreachable, and 'ddl.mode' is 'output'
db-version="PostgreSQL 12 (MatrixDB 4.5.0-enterprise) (Greenplum Database 7.0.0+dev.17410.gedbdb5ef84 build dev) on arm-apple-darwin21.5.0, compiled by Apple clang version 13.0.0 (clang-1300.0.27.3), 64-bit compiled on Jul 5 2022 15:45:24"
[ddl]
only-ddl=true mxshift supports adjusting concurrency during migration. Follow these steps:
controller.concurrency parameter in the configuration file (the one used to start mxshift): [controller]
## The number of tables transferred at the same time
concurrency=xxx Obtain the current process ID of mxshift
Run ps aux ｜ grep mxshift in the terminal and note the number in the second column, {{mxshift PID}}.
Send the SIGUSR2 signal to the mxshift process to reload the configuration and update concurrency
Run kill -SIGUSR2 {{mxshift PID}} in the terminal.
In versions prior to v5.2.1, the [transfer] section contained parameters with-index and verify to control whether indexes were migrated and whether row counts were verified. However, index migration and legacy data verification (i.e., row count check only) were tightly coupled with data migration—they could not run independently and had to occur within the data migration process.
Starting from v5.2.1, index migration and legacy verification can run independently. A new parameter disabled-data-transfer has been added under the [transfer] section to skip data transfer. Examples:
[transfer]
## Whether to disable data transfer; default is false
disabled-data-transfer=false
## Transfer indexes of tables; default is false
with-index=true [transfer]
## Whether to disable data transfer; default is false
disabled-data-transfer=false
## Verify row count per table; default is disabled
verify=true [transfer]
## Whether to disable data transfer; default is false
disabled-data-transfer=false
## Transfer indexes of tables; default is false
with-index=true
## Verify row count per table; default is disabled
verify=true [transfer]
## Whether to disable data transfer; default is false
disabled-data-transfer=false
## Transfer indexes of tables; default is false
with-index=false
## Verify row count per table; default is disabled
verify=false [transfer]
## Whether to disable data transfer; default is false
disabled-data-transfer=true
## Transfer indexes of tables; default is false
with-index=true [transfer]
## Whether to disable data transfer; default is false
disabled-data-transfer=true
## Verify row count per table; default is disabled
verify=true Starting from version v5.2.1, YMatrix mxshift supports a new data verification algorithm configurable via the [verify] section.
For detailed global configuration parameters, see the Appendix. A full example of the [verify] section is provided in the Full Migration Configuration File above. Below we focus on scope configuration.
[verify]
# [[verify.table-list]]
# schema="test_schema_1"
# name="table_001"
# [[verify.exclude-table-list]]
# schema="test_schema_3"
# name="table_003"
# verify.schema-list=["test_schema_1"]
# verify.exclude-schema-list=["test_schema_5"]
# [[verify.override]]
# mode="length-sum"
# max-column-count=3
# columns=[]
# [[verify.override.table-list]]
# schema="test_schema_3"
# name="table_003"
# verify.override.schema-list=[]
# [[verify.override]]
# mode="column-count"
# max-column-count=2
# columns=[]
# [[verify.override.table-list]]
# schema="test_schema_1"
# name="table_001"
# verify.override.schema-list=[] Verification scope is controlled by four sub-sections: [verify.table-list], [verify.exclude-table-list], [verify.schema-list], and [verify.exclude-schema-list].
The priority order is as follows:
table-list lists specific tables, only those tables are verified. schema-list specifies any schemas. verify.table-list: List of tables included in v5.2.1 data verification. verify.exclude-table-list: List of tables excluded from v5.2.1 data verification. verify.schema-list: List of schemas included in v5.2.1 data verification. verify.exclude-schema-list: List of schemas excluded from v5.2.1 data verification. The [verify.override] subsection overrides global verification settings and applies its configurations to tables within the specified scope.
This section describes parameters supported by the mxshift tool.
--- SPLIT ---
Configuration File
To use the mxshift tool, you must first prepare a TOML configuration file. Below is a detailed description of the parameters in the configuration file:
For conditional migration using WHERE conditions, use the following parameters:
| Category | Subcategory | Subparameter | Sub-subcategory | Sub-subparameter | Description | Required |
| [transfer] category | [transfer.table-data-where-sql] category | --enabled | If set to `true`, applies WHERE condition to filter source data, migrating only rows matching the condition—enabling incremental migration. This feature is disabled by default; enable manually with `true`. | No | ||
| --global | SQL `WHERE` expression applied to all tables in this migration. If a table does not contain the `WHERE` keyword, `SKIPPED` automatically skips the table. | No | ||||
| [[transfer.table-data-where-sql.override]] category | --where | WHERE sub-expression, higher priority than global. Applies table-level filtering to specific tables. | No | |||
| [transfer.table-data-where-sql.override.table] category | --schema | Schema name of the table to migrate. | No | |||
| --name | Table name to migrate. | No |
The mxshift command-line options are as follows:
| Option | Description |
|---|---|
| --config | Print default content of the configuration file. |
| -c / --config-path | Path to the global mxshift configuration file. |
| -a / --all | Execute migration without confirmation. Skips already migrated and empty tables by default. |
| -v / --version | Display mxshift tool version. |
| -l / --show-progress | Show progress of the most recent migration. If no migration is ongoing, shows last result. If migration is in progress, shows current status. STATUS values: Not start — not in migration scope; Skip — skipped (already migrated or empty); Processing/Interrupted — currently migrating or interrupted; Complete — migration completed; Failed — migration failed. |
| -R / --redo | Re-migrate tables even if previously migrated (clears existing data in target table before re-migration). |
| --write-table-meta-file | Export metadata of migration tables to mxshift_meta_file file and exit. |
| --read-table-meta-file | Import migration table metadata from mxshift_meta_file file and proceed with data migration. |