Migration Toolkit command options v55
To control details of the migration, append migration options when you run Migration Toolkit. For example, to migrate all schemas in a database, append the -allSchemas
option to the command:
./runMTK.sh -allSchemas
Note
- The
-allSchemas
parameter is supported only for the Oracle, EDB Postgres Advanced Server, and PostgreSQL source database. It isn't supported for Sybase, MS SQL Server, and MySQL source databases. - Migration Toolkit disables the user-created triggers while migrating the data. However, as PostgreSQL/EDB Postgres Advanced Server doesn't allow disabling inherited child partition triggers using the
DISABLE TRIGGER USER
clause inALTER TABLE
, the triggers activate during data migration on partition tables, which can cause unexpected results.
The command options that work with Migration Toolkit are grouped by their behavior, as shown in the table.
Feature | Relevant options |
---|---|
Offline migration options | -offlineMigration |
Import options | -sourcedbtype, -targetdbtype, -schemaOnly, -dataOnly |
Schema creation options | -dropSchema, -targetSchema |
Schema object selection options | -allTables, -tables, -excludeTables, -constraints, -ignoreCheckConstFilter, -skipCKConst, -skipFKConst, -skipColDefaultClause, -indexes, -triggers, -allViews, -views, -excludeViews, -allSequences, -sequences, -excludeSequences, -allProcs, -procs, -excludeProcs, -allFuncs, -funcs, -excludeFuncs, -checkFunctionBodies, -allPackages, -packages, -excludePackages, -allDomains, -allQueues, -queues, -excludeQueues -allRules, -allgroups, -groups |
Migration options | -truncLoad, -enableConstBeforeDataLoad, -retryCount, -safeMode, -fastCopy, -analyze, vacuumAnalyze, -replaceNullChar, -copyDelimiter, -batchSize, -cpBatchSize, -lobBatchSize, -fetchSize, -filterProp -customColTypeMapping, -customColTypeMappingFile -mapVirtualToRegular |
Connection retry options | -connRetryCount, -connRetryInterval, -abortOnConnFailure |
Oracle-specific options | -allUsers, -users, -allProfiles, -profiles, -importPartitionAsTable, -objectTypes, -copyViaDBLinkOra, -allDBLinks -allSynonyms, -allPublicSynonyms, -excludeSynonyms, -allPrivateSynonyms, -useOraCase, -skipUserSchemaCreation |
Miscellaneous options | -help, -logDir, -logFileCount, -logFileSize, -logBadSQL -verbose, -version |
Migration options for parallel data loading | -loaderCount, -parallelLoadRowLimit, -tableLoaderLimit |
Specify options in file | -optionsFile |
Note
If you're using several options for a migration or have to specify a long list of objects for an option, consider using the -optionsFile
option to specify the values in a separate text file. See Specifying options using a file for more information.
Offline migration options
If you specify the -offlineMigration
option in the command line, Migration Toolkit performs an offline migration. During an offline migration, Migration Toolkit reads the definition of each selected object and creates an SQL script that, when executed later, replicates each object in Postgres.
Note
The following examples invoke Migration Toolkit in Linux. To invoke Migration Toolkit in Windows, use the runMTK.bat
command instead of the runMTK.sh
command.
To perform an offline migration of both schema and data, specify the ‑offlineMigration
keyword, followed by the schema scope:
Each database object definition is saved in a separate file with a name derived from each schema name and object type in your home folder. To specify an alternative file destination, include a directory name after the ‑offlineMigration
option:
To perform an offline migration of only schema objects (creating empty tables), specify the ‑schemaOnly
keyword in addition to the ‑offlineMigration
keyword when invoking Migration Toolkit:
To perform an offline migration of only data, omitting any schema object definitions, specify the ‑dataOnly
keyword and the ‑offlineMigration
keyword when invoking Migration Toolkit:
By default, data is written in COPY format. To write the data in a plain SQL format, include the ‑safeMode
keyword:
By default, when you perform an offline migration that contains table data, a separate file is created for each table. To create a single file that contains the data from multiple tables, specify the ‑singleDataFile
keyword:
Note
The -singleDataFile
option is available only when migrating data in a plain SQL format. You must include the -safeMode
keyword if you include the ‑singleDataFile
option.
Executing offline migration scripts
You can use the edb-psql or psql command line to execute the scripts generated during an offline migration. The following example describes restoring a schema (named hr) into a new database (named acctg) stored in EDB Postgres Advanced Server.
Use the
createdb
command to create the acctg database, into which you'll restore the migrated database objects:Connect to the new database with edb-psql:
Use the
\i
meta-command to invoke the migration script that creates the object definitions:If the
-offlineMigration
command included the‑singleDataFile
keyword, themtk_hr_data.sql
script will contain the commands required to re-create all of the objects in the new target database. Populate the database with the command:
Import options
By default, Migration Toolkit assumes the source database is Oracle and the target database is EDB Postgres Advanced Server. Include the ‑sourcedbtype
and -targetdbtype
keywords to specify a nondefault source or target database.
By default, Migration Toolkit imports both the data and the object definition when migrating a schema. Alternatively, you can choose to import either the data or the object definitions.
-sourcedbtype <source_type>
The -sourcedbtype
option specifies the source database type. For source_type
, use one of the following values: mysql
, oracle
, sqlserver
, sybase
, postgresql
or enterprisedb
. source_type
isn't case sensitive. By default, source_type
is oracle
.
-targetdbtype <target_type>
The -targetdbtype
option specifies the target database type. For target_type
, use one of the following values: enterprisedb
, postgres
, or postgresql
. target_type
isn't case sensitive. By default, target_type
is enterprisedb
.
-schemaOnly
This option imports the schema definition and creates all selected schema objects in the target database. You can't use this option with the ‑dataOnly
option.
-dataOnly
This option copies only the data. When used with the -tables
option, Migration Toolkit imports data only for the selected tables. You can't use this option with the -schemaOnly
option.
Schema creation options
By default, Migration Toolkit imports the source schema objects or data into a schema of the same name. If the target schema doesn't exist, Migration Toolkit creates a schema. Alternatively, you can specify a custom schema name by using the ‑targetSchema
option. You can choose to drop the existing schema and create a new schema using the following option:
-dropSchema [true|false]
With this option set to true
, Migration Toolkit drops the existing schema and any objects in that schema and creates a new schema. By default, -dropSchema
is false
.
-targetSchema <schema_name>
Use the -targetSchema
option to specify the name of the migrated schema. If you're migrating multiple schemas, specify a name for each schema in a comma-separated list with no intervening space characters. Without the -targetSchema
option, the name of the new schema is the same as the name of the source schema.
You can't specify information-schema
, dbo
, sys
, or pg_catalog
as target schema names. These schema names are reserved for metadata storage in EDB Postgres Advanced Server.
Schema object selection options
Use the following options to select specific schema objects to migrate.
-allTables
Import all tables from the source schema.
-tables <table_list>
Import the selected tables from the source schema. table_list
is a comma-separated list of table names with no intervening space characters.
For example: -tables emp,dept,acctg
When migrating multiple schemas or all schemas (with the -allSchemas
option), the table name must be schema-qualified.
For example: -allSchemas -tables comp_schema.emp,comp_schema.dept,finance_schema.acctg
-excludeTables <table_list>
Exclude the selected tables from migration. The table_list
is a comma-separated list of table names with no intervening space characters. This option applies when all tables from a schema are selected for migration using the -allTables
option.
For example: -allTables -excludeTables emp,jobhist
When migrating multiple schemas or all schemas (with the -allSchemas
option), the excluded table name must be schema-qualified.
For example: -allSchemas -allTables -excludeTables comp_schema.emp,finance_schema.jobhist
-constraints
Import the table constraints. This option is valid only when importing an entire schema or when you specify the -allTables
or -tables <table_list>
options.
-ignoreCheckConstFilter
By default, Migration Toolkit doesn't implement migration of check constraints and default clauses from a Sybase database. To migrate constraints and default clauses from a Sybase database, include the ‑ignoreCheckConstFilter
parameter when specifying the -constraints
parameter.
-skipCKConst
Omit the migration of check constraints. This option is useful when migrating check constraints that are based on built-in functions in the source database that aren't supported in the target database.
This option is valid only when importing an entire schema or when the -allTables
or -tables <table_list>
options are specified.
-skipFKConst
Omit migrating foreign-key constraints. This option is valid only when importing an entire schema or when the -allTables
or -tables <table_list>
options are specified.
-skipColDefaultClause
Omit migrating the column DEFAULT
clause.
-indexes
Import the table indexes. This option is valid when importing an entire schema or when the -allTables
or -tables <table_list>
option is specified.
-triggers
Import the table triggers. This option is valid when importing an entire schema or when the allTables
or -tables <table_list>
option is specified.
-allViews
Import the views from the source schema. This option migrates dynamic and materialized views from the source. Oracle and Postgres materialized views are supported.
-views <view_list>
Import the specified materialized or dynamic views from the source schema. Oracle and Postgres materialized views are supported. view_list
is a comma-separated list of view names with no intervening space characters.
For example: -views all_emp,mgmt_list,acct_list
When migrating multiple schemas or all schemas (with the -allSchemas
option), the view name must be schema-qualified.
For example: -allSchemas -views comp_schema.all_emp,comp_schema.mgmt_list,finance_schema.acct_list
-excludeViews <view_list>
Exclude the selected views from migration. The view_list
is a comma-separated list of view names with no intervening space characters. This option applies when all views from a schema are selected for migration using the -allViews
option.
For example: -allViews -excludeViews all_emp,acct_list
When migrating multiple schemas or all schemas (with the -allSchemas
option), the excluded view name must be schema-qualified.
For example: -allSchemas -allViews -excludeViews comp_schema.all_emp,finance_schema.acct_list
-allSequences
Import all sequences from the source schema.
-sequences <sequence_list>
Import the selected sequences from the source schema. <sequence_list>
is a comma-separated list of sequence names with no intervening space characters.
For example: -sequences my_sequence,my_sequence_with_increment
When migrating multiple schemas or all schemas (with the -allSchemas
option), the sequence name must be schema-qualified.
For example: -allSchemas -sequences comp_schema.my_sequence,finance_schema.my_sequence_with_increment
-excludeSequences <sequence_list>
Exclude selected sequences from the migration.
The sequence_list
is a comma-separated list of sequence names with no intervening space characters.
This option applies when all sequences from a schema are selected for migration using the -allSequences
option.
For example: -allSequences -excludeSequences my_sequence,my_sequence_with_increment
When migrating multiple schemas or all schemas (with the -allSchemas
option), the excluded sequence name must be schema-qualified.
For example: -allSchemas -allSequences -excludeSequences comp_schema.my_sequence,finance_schema.my_sequence_with_increment
-allProcs
Import all stored procedures from the source schema.
-procs <procedures_list>
Import the selected stored procedures from the source schema. procedures_list
is a comma-separated list of procedure names with no intervening space characters.
For example: -procs show_notice,show_custom_notice
When migrating multiple schemas or all schemas (with the -allSchema
option), the procedure name must be schema-qualified.
For example: -allSchema -procs comp_schema.show_notice,finance_schema.show_custom_notice
-excludeProcs <procedures_list>
Exclude selected procedures from migration.
The procedures_list
is a comma-separated list of procedure names with no intervening space characters.
This option applies when all procedures from a schema are selected for migration using the -allProcs
option.
For example: -allProcs -excludeProcs show_notice,show_custom_notice
When migrating multiple schemas or all schemas (with the -allSchemas
option), the excluded procedure name must be schema-qualified.
For example: -allSchemas -allProcs -excludeProcs comp_schema.show_notice,finance_schema.show_custom_notice
-allFuncs
Import all functions from the source schema.
-funcs <function_list>
Import the selected functions from the source schema. function_list
is a comma-separated list of function names with no intervening space characters.
For example: -funcs calculate_average_salary,add_two_numbers
When migrating multiple schemas or all schemas (with the -allSchemas
option), the function name must be schema-qualified.
For example: -allSchemas -funcs comp_schema.calculate_average_salary,finance_schema.add_two_numbers
-excludeFuncs <function_list>
Exclude selected functions from migration.
The function_list
is a comma-separated list of function names with no intervening space characters.
This option applies when all functions from a schema are selected for migration using the -allFuncs
option.
For example: -allFuncs -excludeFuncs calculate_average_salary,add_two_numbers
When migrating multiple schemas or all schemas (with the -allSchemas
option), the excluded function name must be schema-qualified.
For example: -allSchemas -allFuncs -excludeFuncs comp_schema.calculate_average_salary,finance_schema.add_two_numbers
-checkFunctionBodies [true/false]
When false
, disables validation of the function body during function creation. Disabling this validation avoids errors if the function contains forward references. The default value is true
.
-allPackages
Import all packages from the source schema.
-packages <package_list>
Import the selected packages from the source schema. package_list
is a comma-separated list of package names with no intervening space characters.
For example: -packages my_package1, mypackage2
When migrating multiple schemas or all schemas (with the -allSchemas
option), the package name must be schema-qualified.
For example: -allSchemas -packages comp_schema.my_package1,finance_schema.mypackage2
-excludePackages <package_list>
Exclude selected packages from migration.
The package_list
is a comma-separated list of package names with no intervening space characters.
This option applies when all packages from a schema are selected for migration using the -allPackages
option.
Example: -allPackages -excludePackages my_package1, mypackage2
When migrating multiple schemas or all schemas (with the -allSchemas
option), the excluded package name must be schema-qualified.
For example: -allSchemas -allPackages -excludePackages comp_schema.my_package1,finance_schema.mypackage2
-allDomains
Import all domain, enumeration, and composite types from the source database. This option is valid only when both the source and target are stored on a Postgres host.
-allQueues
Import all queues from the source schema. These are queues created and managed by the DBMS_AQ and DBMS_AQADM built-in packages. When Oracle is the source database, you must also specify the -objectTypes
option. When EDB Postgres Advanced Server is the source database, you must also specify the -allDomains
and -allTables
options. Oracle and EDB Postgres Advanced Server queues are supported.
-queues <queue_list>
Import the selected queues from the source schema. queue_list
is a comma-separated list of queue names with no intervening space characters. These are queues created and managed by the DBMS_AQ and DBMS_AQADM built-in packages. When Oracle is the source database, you must also specify the -objectTypes
. When EDB Postgres Advanced Server is the source database, you must also specify -allDomains
and -allTables
. Oracle and EDB Postgres Advanced Server queues are supported.
-excludeQueues <queue_list>
Exclude selected queues from migration.
The queue_list
is a comma-separated list of queue names with no intervening space characters.
This option applies when all queues from a schema are selected for migration using the -allQueues
option.
Example: -allQueues -excludeQueues EMP_QUEUE1,EMP_QUEUE2
-allRules
Import all rules from the source database. This option is valid only when both the source and target are stored on a Postgres host.
-allGroups
Import all groups from the source database.
-groups <group_list>
The selected groups from the source database. The <group_list>
is a comma-separated list of group names e.g. -groups acct_emp,mkt_emp
.
Migration options
Use the migration options to control the details of the migration process.
-truncLoad
Truncate the data from the table before importing new data. Use this option with the -dataOnly
option.
-enableConstBeforeDataLoad
Include the -enableConstBeforeDataLoad
option if a nonpartitioned source table is mapped to a partitioned table. This option enables all triggers on the target table, including any triggers that redirect data to individual partitions, before the data migration. -enableConstBeforeDataLoad
is valid only if you also specify the -truncLoad
parameter.
-retryCount [<value>]
If you're performing a multiple-schema migration, objects that fail to migrate during the first migration attempt due to cross-schema dependencies might successfully migrate during a later migration. Use the -retryCount
option to specify the number of attempts for Migration Toolkit to make to migrate an object that failed during an initial migration attempt. Specify a value greater than 0. The default value is 2.
-safeMode
If you include the -safeMode
option, Migration Toolkit commits each row as migrated. If the migration fails to transfer all records, rows inserted prior to the point of failure remain in the target database.
-fastCopy
Including the -fastCopy
option specifies for Migration Toolkit to bypass WAL logging to perform the COPY operation in an optimized way. It is disabled by default. If you choose to use the -fastCopy
option, you might not be able to recover the migrated data in the target database if the migration is interrupted.
-replaceNullChar <value>
The Migration Toolkit supports importing a column with a value of NULL. However, the Migration Toolkit doesn't support importing NULL character values (embedded binary zeros 0x00) with the JDBC connection protocol. If you're importing data that includes the NULL character, use the -replaceNullChar
option to replace the NULL character with a single, non-NULL replacement character. Don't enclose the replacement character in quotes or apostrophes.
Once the data is migrated, use a SQL statement to replace the character specified by -replaceNullChar
with binary zeros.
-analyze
Include the -analyze
option to invoke the Postgres ANALYZE
operation against a target database. The optimizer consults the statistics collected by the ANALYZE
operation, using the information to construct efficient query plans.
-vacuumAnalyze
Include the -vacuumAnalyze
option to invoke both the VACUUM
and ANALYZE
operations against a target database. The optimizer consults the statistics collected by the ANALYZE
operation, using the information to construct efficient query plans. The VACUUM
operation reclaims any storage space occupied by dead tuples in the target database.
-copyDelimiter
Specify a single character to use as a delimiter in the COPY command when loading table data. The default value is '\t'
(tab).
-batchSize
Specify the batch size of bulk inserts. Valid values are 1 to 1000. The default batch size is 1000. Reduce the value of -batchSize
if Out of Memory exceptions occur.
-cpBatchSize
Specify the batch size in MB to use in the COPY command. Any value greater than 0 is valid. The default batch size is 8MB.
-lobBatchSize
Specify the number of rows to load in a batch for LOB data types. The data migration for a table containing a large object type (LOB) column, such as BYTEA
, BLOB
, or CLOB
, is performed one row at a time by default. This is to avoid an out-of-heap-space error in case an individual LOB column holds hundreds of megabytes of data. In case the LOB column average data size is at a lower end, you can customize the LOB batch size by specifying the number of rows in each batch with any value greater than 0.
-fetchSize
Use the -fetchSize
option to specify the number of rows fetched in a result set. If the designated -fetchSize
is too large, you might encounter Out of Memory exceptions. Include the -fetchSize
option to avoid this pitfall when migrating large tables. The default fetch size is specific to the JDBC driver implementation and varies by database.
MySQL users note: By default, the MySQL JDBC driver fetches all of the rows in a table into the Migration Toolkit in a single network round trip. This behavior can easily exceed available memory for large tables. If you encounter an out-of-heap-space error, specify -fetchSize 1
as a command line argument to force Migration Toolkit to load the table data one row at a time.
-filterProp <file_name>
<file_name>
specifies the name of a file that contains constraints in key=value pairs. Each record read from the database is evaluated against the constraints. Those that satisfy the constraints are migrated.
The left side of the pair lists a table name:
- The table name must not be schema qualified.
- Oracle table names aren't case sensitive, but Oracle defaults to uppercase. Postgres, on the other hand, defaults to lowercase. When migrating Oracle data, ensure the case you're using matches the case in Oracle. Otherwise, Migration Toolkit can't match it and ignores the constraint.
The right side specifies a condition that must be true for each row migrated.
For example, this code migrates only those countries with a COUNTRY_ID
value that isn't equal to AR
:
COUNTRIES=COUNTRY_ID<>'AR'
This constraint applies to the COUNTRIES table.
You can also specify conditions for multiple tables. However, the condition for each table must be on a new line in the property file.
Example:
The following entries in the properties file migrate only the relevant data from EMPLOYEES and the DEPARTMENTS tables:
EMPLOYEES=(LAST_NAME IN ('Grant','Weiss') AND PHONE_NUMBER LIKE '650%')
DEPARTMENTS=(DEPARTMENT_ID BETWEEN 10 AND 30)
-customColTypeMapping <column_list>
Use custom type mapping to change the data type of migrated columns. The left side of each pair specifies the columns with a regular expression. The right side of each pair names the data type for that column to assume. You can include multiple pairs in a semi-colon-separated list for <column_list>
. For example, to map any column whose name ends in ID
to type INTEGER
, use the following custom mapping entry:
.*ID=INTEGER
Custom mapping is applied to all table columns that match the criteria unless the column is table qualified.
The '\\'
characters act as an escape string. Since '.'
is a reserved character in regular expressions, on Linux use '\\.'
to represent the '.'
character. For example, to use custom mapping to select rows from the EMP_ID
column in the EMP
table, specify the following custom mapping entry:
EMP\\.EMP_ID=INTEGER
On Windows, use '\.'
to represent the '.'
character:
EMP\.EMP_ID=INTEGER
Alternatively, you can include multiple custom type mappings in a <property_file>
:
-customColTypeMappingFile <property_file>
Specify each entry in the file on a separate line in a key=value pair. The left side of each pair selects the columns with a regular expression. The right side of each pair names the data type for that column to assume. When used in the <property_file>
, the '\\'
characters act as an escape string in any operating system.
-mapVirtualToRegular
Include the -mapVirtualToRegular
option to migrate virtual, computed, or generated columns in the source database to regular columns in the target database.
Turning virtual columns to regular columns is helpful when the expression used to compute the values in the source database column isn't supported in the target database or can't be translated into an expression supported by the target database. With this option, you can still migrate the column's values to the target, but the values will no longer be computed dynamically, as they're stored in a regular column.
For schema migrations, including the option results in all virtual columns in the source database being migrated to regular columns in the target database.
For data migrations, including the option extracts the computed values from all computed columns in the source database and inserts those values into regular columns in the target database.
In the following example, a column FullName
is computed from other two columns called FirstName
and LastName
in the source database. This column is migrated as a regular column called FullName
in the target database.
In the target, this column is no longer dynamically generated but displays the FullName
value the source database had at the time the migration was performed.
Connection retry options
Whenever there's a connection failure with the target database during a data migration, Migration Tookit attempts to reconnect to the target database to ensure the migration completes without skipping any tables. When the connection is reestablished, Migration Toolkit restarts or resumes the data copy for the table that was being migrated when the connection was lost. It then performs the data copy for the remaining tables.
Migration Toolkit resumes the migration based on the mode that it was using to migrate the data:
If Migration Toolkit was using Copy API to migrate the data, it continues copying data from the last failed row. Copy API is compatible with PostgreSQL and EDB Postgres Advanced Server as target databases.
In other data migration modes, Migration Toolkit truncates the data on the target table and recopies the entire failed table.
Scope and limitations
Database scope: The connection retry capability allows Migration Toolkit to reconnect to the target database. Retry attempts for issues with the source database aren't supported.
Migration scope: This capability allows Migration Toolkit to retry migrating data. Retry attempts for issues with the schema migration aren't supported.
Modality scope: This reconnection capability is available with the data migration mode (-dataOnly
).
It's also available when you run a migration without specifying either the -dataOnly
or -schemaOnly
options.
You can specify several connection retry options:
-connRetryCount [<connection_attempts>]
Use the -connRetryCount
option to specify the number of retry attempts to perform if the target database connection fails.
The [<connection_attempts>]
value must be a number between 0 and 50. The default is 3 retry attempts.
Since the retry applies to the migration of data, it isn't compatible with the -schemaOnly
option.
Example:
-connRetryInterval [<seconds>]
Use the -connRetryInterval
option to specify the seconds to wait before each subsequent reconnection attempt
if the target database connection fails.
The [<seconds>]
value must be a number between 0 and 900. The default is 30 seconds.
Since the retry applies to the migration of data, it isn't compatible with the -schemaOnly
option.
Example:
-abortConnOnFailure
[true/false]`
Specify whether to abort the migration if all the reconnection attempts failed.
To skip migrating the failed table and proceed to the next table, set the -abortConnOnFailure
to false
.
The default is true
, which aborts the session if the connection fails after the specified -connRetryCount
threshold.
Since the retry applies to the migration of data, it isn't compatible with the -schemaOnly
option.
Example:
-pgIdleTxSessionTimeOut [<seconds>]
Specify the PostgreSQL or EDB Postgres Advanced Server idle_in_transaction_session_timeout
, which defines the time after which
the database terminates the session when a migration transaction is in idle state.
[<seconds>]
is a value greater than 0. The default is 180 seconds.
Example:
Migration options for parallel data loading
When dealing with a relatively large number of tables or large tables, normal data migration takes a long time. As a solution to this problem, Migration Toolkit has a parallel data loading algorithm that allows migrating data in parallel at the schema level and at the table level.
Parallel data migration at the schema level uses multiple threads to migrate several tables at the same time. Parallel data loading at the table level uses multiple threads to migrate a single table from the source database to the target database more efficiently and in a shorter time.
Notes
Parallel loading is useful only for large tables. For small tables, parallel threads might take more time. Thus we recommend using parallel data loading at the table level for relatively large tables.
Parallel data loading doesn't apply to tables without a primary/unique key.
You can't use the
fastCopy
parameter with parallel data loading.Parallel loading functionality applies only to the source Oracle, EDB Postgres Advanced Server, and PostgreSQL databases.
Migrations from Oracle databases
Because parallel data loading uses Oracle Flashback queries to perform data loading, ensure the user performing the migration has FLASHBACK
and READ
/ SELECT
privileges to the table objects to migrate. To allow queries on all tables, grant the FLASHBACK ANY TABLE
privilege.
The following options control the way MTK migrates data in parallel.
-loaderCount [<value>]
Use the -loaderCount
option to specify the number of parallel threads available in the pool to perform data load in parallel. This option is particularly useful if the host system that's running Migration Toolkit has high-end CPU and RAM resources. While value
can be any nonzero, positive number, we recommend that value not exceed the number of CPU cores. For example, a dual-core CPU has an optimal value of 2
. The default is 1
.
The number of table-level threads can introduce overhead on the source database server depending on the table size and certain memory configurations, like shared_buffers
and work_mem
(memory configuration should be set to optimal values for the database server). It is recommended that for very large tables you try the lower -loaderCount
option value, according to the total cores available on the machine, to calculate the optimal -loaderCount
value.
Note
When multiple threads are used, depending on the actual number of threads and table data size, you might need to adjust the memory heap size for the Migration Toolkit.
-parallelLoadRowLimit [<value>]
Use the -parallelLoadRowLimit
option to specify the minimum number of rows required in a table to perform data load in parallel at the table level. The <value>
parameter must be greater than 0. The default is 100,000.
For example, if the value of -parallelLoadRowLimit
is 10,000, only tables with the number of rows 10,000 and greater are loaded in parallel at the table level. The other tables migrate in sequential mode or at the schema level.
-tableLoaderLimit [<value>]
Use the -tableLoaderLimit
option to specify the maximum number of threads to assign from the thread pool to load a single table data in parallel chunks at the table level. The <value>
parameter must not be greater than the value of -loaderCount
. The default value is equal to the value of the -loaderCount
option. This option is implicitly changed based on the nondefault custom value of -loaderCount
.
For example, if the -loaderCount
is set to 4
and -tableLoaderLimit
isn't specified, the -tableLoaderLimit
is also set to 4
. Hence, if all threads aren't meant to be used for a single table load, reduce the -tableLoaderLimit
to a lower value.
High-level overview of the parallel data-loading algorithm
The algorithm works in three steps:
A list of tables and table chunks is created from the ordered list of tables to migrate, sorted by the table name. The list is created based on the
-parallelLoadRowLimit
and-tableLoaderLimit
option values.A thread pool is created based on the
-loaderCount
option value.The parallel data-loading algorithm creates tasks for each table/chunk from the list of tables and table chunks and executes them in the thread pool. As many tasks as the number of threads are executed in parallel. As soon as a task execution completes, its thread starts executing the next task from the list. Parallel data loading completes as soon as the last task from the list completes.
Example
In this scenario, migrate four tables—tab1, tab2, tab3, tab4
—with parallel data loading:
Table tab1
has 50,000 rows, table tab2
has 9,500 rows, table tab3
has 50,001 rows and table tab4
has 9,999 rows. The list of tables for step 1 is tab1, tab2, tab3
, and tab4
.
Only tables tab1
and tab3
qualify for parallel loading on table level (-parallelLoadRowLimit 10000
).
Since the value of the -tableLoaderLimit
option is 2
, table tab1
is loaded in two chunks, tab1_chunk1
and tab1_chunk2
. The number of rows in each chunk is determined based on the totalRowCount/tableLoaderLimit
. In this case, both chunks have 25,000 rows (50,000/2).
Table tab3
is also loaded in two chunks, tab3_chunk1
and tab3_chunk2
. As the total number of rows in table tab3
is odd (50,001
), the first chunk accommodates an additional row, so tab3_chunk1
has 25,001 rows, and tab3_chunk2
has 25,000 rows.
Here's the list of tables and table chunks created:
Thread pool with the four threads T1, T2, T3, T4
is created.
Tasks migrating tables/chunks from the list created in step 1 are executed in the thread pool:
Thread T3
finishes first and starts executing tab3_chunk2
, the next chunk in the list:
Thread T1
finishes second and starts executing tab4
:
This way, four threads are used to migrate four tables in parallel at the mixed-schema and table level.
If you change command options to set -tableLoaderLimit
to 1
, you can have pure schema-level parallelism:
Each table is processed simultaneously in one thread:
System resource recommendations and constraints
Choose the number of threads depending on the CPU and RAM resources available on the host system running Migration Toolkit. As there's a certain overhead on the source database in terms of CPU, IO, and disk use, exceeding parallel thread count beyond a certain threshold degrades Migration Toolkit performance.
Oracle-specific options
The following options apply only when the source database is Oracle.
-objectTypes
Import the user-defined object types from the schema list specified at the end of the runMTK.sh
command.
-allUsers
Import all users and roles from the source database. The ‑allUsers
option is supported only when migrating from an Oracle database to an EDB Postgres Advanced Server database.
-users <user_list>
Import the selected users or roles from the source Oracle database. <user_list>
is a comma-separated list of user/role names with no intervening space characters (e.g., -users MTK, SAMPLE, acctg
). The -users
option is supported only when migrating from an Oracle database to an EDB Postgres Advanced Server database.
-allProfiles
Import all custom (that is, user-created) profiles from the source database. Other Oracle noncustom profiles such as DEFAULT
and MONITORING_PROFILE
aren't imported.
For the imported profiles, only the following password parameters associated with the profiles are imported:
FAILED_LOGIN_ATTEMPTS
PASSWORD_LIFE_TIME
PASSWORD_REUSE_TIME
PASSWORD_REUSE_MAX
PASSWORD_LOCK_TIME
PASSWORD_GRACE_TIME
PASSWORD_VERIFY_FUNCTION
All other profile parameters, such as the Oracle resource parameters, aren't imported. The Oracle database user specified by SRC_DB_USER
must have SELECT
privilege on the Oracle data dictionary view DBA_PROFILES
.
Note
The ‑allProfiles
option is supported only when migrating from an Oracle database to an EDB Postgres Advanced Server database.
-profiles <profile_list>
Import the selected, custom (that is, user-created) profiles from the source Oracle database. profile_list
is a comma-separated list of profile names with no intervening space characters (e.g., -profiles ADMIN_PROFILE,USER_PROFILE
). Oracle noncustom profiles such as DEFAULT
and MONITORING_PROFILE
aren't imported.
As with the -allProfiles
option, only the password parameters are imported. The Oracle database user specified by SRC_DB_USER
must have SELECT
privilege on the Oracle data dictionary view DBA_PROFILES
.
Note
The -profiles
option is supported only when migrating from an Oracle database to an EDB Postgres Advanced Server database.
-importPartitionAsTable <table_list>
Include the -importPartitionAsTable
parameter to import the contents of a partitioned table that resides on an Oracle host into a single nonpartitioned table. table_list
is a comma-separated list of table names with no intervening space characters (for example, -importPartitionAsTable emp,dept,acctg
).
-copyViaDBLinkOra
The dblink_ora
module provides EDB Postgres Advanced Server-to-Oracle connectivity at the SQL level. dblink_ora
is bundled and installed as part of the EDB Postgres Advanced Server database installation. dblink_ora
uses the COPY API
method to transfer data between databases. This method is considerably faster than the JDBC COPY
method.
This example uses the dblink_ora
COPY API
to migrate all tables from the HR
schema:
The target EDB Postgres Advanced Server database must have dblink_ora
installed and configured. See dblink_ora.
-allDBLinks [link_Name_1=password_1,link_Name_2=password_2,...]
Choose this option to migrate Oracle database links. The password information for each link connection in the source database is encrypted so, unless specified, the dummy password edb is substituted.
To migrate all database links using edb as the dummy password for the connected user:
You can alternatively specify the password for each of the database links through a comma-separated list of name=value pairs with no intervening space characters. Specify the link name on the left side of the pair and the password value on the right side.
To migrate all database links with the actual passwords specified on the command line:
Migration Toolkit migrates only the database link types that are currently supported by EnterpriseDB. These types include fixed user links of public and private type.
-allSynonyms
Include the -allSynonyms
option to migrate all public and private synonyms from an Oracle database to an EDB Postgres Advanced Server database. If a synonym with the same name already exists in the target database, the existing synonym is replaced with the migrated version.
-allPublicSynonyms
Include the -allPublicSynonyms
option to migrate all public synonyms from an Oracle database to an EDB Postgres Advanced Server database. If a synonym with the same name already exists in the target database, the existing synonym is replaced with the migrated version.
-excludeSynonyms <synonym_list>
Exclude selected synonyms from migration.
The synonym_list
is a comma-separated list of synonym names with no intervening space characters.
This option applies when all synonyms from a schema are selected for migration using the -allSynonyms
option.
Example: -allSynonyms -excludeSynonyms SYNEMP1,SYNEMP2
-allPrivateSynonyms
Include the -allPrivateSynonyms
option to migrate all private synonyms from an Oracle database to an EDB Postgres Advanced Server database. If a synonym with the same name already exists in the target database, the existing synonym is replaced with the migrated version.
-useOraCase
Include the -useOraCase
option to preserve the Oracle default, uppercase naming convention for all database objects when migrating from an Oracle database to an EDB Postgres Advanced Server database.
The uppercase naming convention is preserved for tables, views, sequences, procedures, functions, triggers, packages, and so on. For these database objects, the uppercase naming convention applies to:
- The names of the database objects
- The column names, key names, index names, constraint names, and so on, of the tables and views
- The
SELECT
column list for a view - The parameter names that are part of the procedure or function header
Note
In the procedural code body of a procedure, function, trigger, or package, you might have to manually edit identifier references for the program to execute without an error. Such corrections are in regard to the proper case conversion of identifier references that might have occurred.
Note
When you specify the -useOraCase
option, you might need to specify the -skipUserSchemaCreation
option as well. For information, see the description of the -skipUserSchemaCreation
option.
The default behavior of the Migration Toolkit without the -useOraCase
option is that database object names are extracted from Oracle without enclosing quotation marks unless the database object was explicitly created in Oracle with enclosing quotation marks. The following is a portion of a table command generated by the Migration Toolkit with the -offlineMigration
option:
When you then migrate this table and create it in EDB Postgres Advanced Server, all unquoted object names are converted to lowercase letters, so the table appears in EDB Postgres Advanced Server as follows:
If your EDB Postgres Advanced Server applications are referencing the migrated database objects using quoted uppercase identifiers, the applications fail since the database object names are now in lower case:
If your application uses quoted uppercase identifiers, perform the migration with the -useOraCase
option. The DDL encloses all database object names in quotes:
When you then migrate this table and create it in EDB Postgres Advanced Server, all object names are maintained in uppercase letters, so the table appears in EDB Postgres Advanced Server as follows:
Applications can then access the object using quoted uppercase names:
-skipUserSchemaCreation
When an Oracle user is migrated, a role (that is, a user name) is created in the target database server for the Oracle user if the role doesn't already exist. The role name is created in lowercase letters. When a new role is created, a schema with the same name is also created in lowercase letters.
Specifying the -skipUserSchemaCreation
option prevents the automatic schema creation for a migrated Oracle user name. This option is particularly useful when the -useOraCase
option is specified to prevent creating two schemas with the same name where only the case is different. Specifying the -useOraCase
option results in creating a schema in the Oracle naming convention of uppercase letters for the source schema specified following the options list when Migration Toolkit is invoked.
Thus, if the -useOraCase
option is specified without the -skipUserSchemaCreation
option, the target database results in having two identically named schemas with one in lowercase letters and the other in uppercase letters. If the -useOraCase
option is specified along with the -skipUserSchemaCreation
option, the target database has only the schema in uppercase letters.
Miscellaneous options
Use these migration options to view Migration Toolkit help and version information. You can also use these options to control Migration Toolkit feedback and logging options.
-help
Display the application command-line usage information.
-logDir <log_path>
Include this option to specify where to write the log files. <log_path>
is the location for saving log files. By default, on Linux log files are written to:
$HOME/.enterprisedb/migration-toolkit/logs
On Windows, the log files are saved to:
%HOMEDRIVE%%HOMEPATH%\.enterprisedb\migration-toolkit\logs
-logFileCount <file_count>
Include this option to specify the number of files used in log file rotation. Specify a value of 0
to disable log file rotation and create a single log file. This file is truncated when it reaches the value specified using the logFileSize
option. <file_count>
must be greater than or equal to 0. The default is 20.
-logFileSize <file_size>
Include this option to specify the maximum file size limit in MB before rotating to a new log file. file_size
must be greater than 0. The default is 50.
-logBadSQL
Include this option to save the schema definition (DDL script) of any failed objects to a file. The file is saved under the same path used for the error logs and is named in the format:
mtk_bad_sql_<schema_name_timestamp>.sql
Where schema_name
is the name of the schema and timestamp
is the timestamp of the Migration Toolkit run.
-verbose [on|off]
Display application log messages on standard output. By default, verbose is on.
-version
Display the Migration Toolkit version.
Example
This example performs a migration from Oracle to EDB Postgres Advanced Server.
The following is the content of the toolkit.properties
file:
The following command invokes Migration Toolkit:
Skipped and unsupported database objects are omitted. The migration information is summarized in the Migration Summary at the end of the run.