This is an old revision of the document!
How to Optimize the Migration Process for Large Tables
There are several ways to reduce migration time and speed up the migration process.
- If there have been no problems during the export you can disable the trace mode. Thus there will be no trace generation which will help to reduce migration time.
- You can split the data into parts and run the migrations simultaneously in our tool. This can be done in two ways:
- Using Data Options
- Using the Queries
Using Data Options
When you select “Data Options” tab for tables you see Edit boxes for the start row and the number of rows to be exported (please see below). By varying these numbers in separate instances of SQLWays Wizard (like 1-5000, 5001-10000, etc.) you can run the migration of different parts of data simultaneously.
Please also note that you should uncheck “Generate DDL” option for the processes other than the first one in order to avoid the error of table existence. In this case only data will be migrated.
Using the Queries
You can export data according to unique index or primary key or any other query condition. To perform this in SQLWays Wizard please select “Use Query” in combo-box shown below. Using this option you can write your own query to select data. DDL statement will be generated according to the selected columns. Table name will be the same as in FROM clause. But we advise you to create empty tables first and then to perform the migration of data. You’ll get errors when trying to create a table but data will be loaded correctly.
For both these solutions please make sure that the “Generate the DROP TABLE statement” check-box is unchecked at the options page. Please also use separate project directories for each migration to prevent project files recreation.
If you face any difficulties or have any other questions, please contact our support team: support@ispirer.com