The PE passes the PLAN to the AMPs over the BYNET. The AMPs then retrieve the rows they own from their disks and pass it back to the PE over the BYNET.
When a table is first created each AMP creates a table header on their disk. Even though the table is empty the AMPs at least know the table name, the columns in the table, and any indexes the table.
When the table is loaded each AMP receives rows for that table that they and only they own. They carefully place the rows inside data blocks where they can easily be retrieved.
Now each AMP will own their own Table Header for the table and they will also own data blocks where they place the rows for that table
Teradata lays out data like this!
When a table is first created each AMP creates a table header on their disk. Even though the table is empty the AMPs at least know the table name, the columns in the table, and any indexes the table.
When the table is loaded each AMP receives rows for that table that they and only they own. They carefully place the rows inside data blocks where they can easily be retrieved.
Now each AMP will own their own Table Header for the table and they will also own data blocks where they place the rows for that table
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| AMP |
Teradata took every table and spread the rows across all the AMPs in the system and the birth of parallel processing happened.
The first picture on the opposite page never happens. The second picture below that is exactly the design behind Teradata.
Teradata NEVER lays out data like this
The first picture on the opposite page never happens. The second picture below that is exactly the design behind Teradata.
Teradata NEVER lays out data like this
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