5.2 Managing Target Tables and Schemas
Managing target tables and schemas involves designing, implementing, and maintaining the structure of your data warehouse. This is a critical task for ensuring data integrity and optimizing performance.
Planning and Design
Before creating tables, it is important to plan the structure of your schema .
🡆Define a Schema Structure: You should choose a schema design like a star or snowflake schema to meet your data warehousing needs.
🡆Design Tables: Plan tables by considering how data blocks will be used, storage parameters, and performance implications .
🡆Organize Tables: Grouping related tables into logical schemas helps with organization and management.
Implementation
🡆Create Tables: Use SQL commands, such as CREATE TABLE mytable(id int, name varchar(20)); or a graphical interface to create new tables .
🡆Create Schemas: Create new schemas to logically group your tables .
🡆Link Tables: In some tools, you can link a new table to a target table through a specific statement .
Management and Maintenance
🡆Handle Schema Changes: When a source schema changes, you may need to stop replication, refresh the schema information, and then re-enable replication .
🡆Refresh Schema Information: After making changes to your tables or schemas, you should refresh the schema information in your ETL tool to ensure it is aware of the new structure .