Estimating Space Requirements
This section discusses space requirements for the Teradata TPump log table.
A row of approximately 200 bytes is written to the log table on each of the following events.
The partial checkpoint row contains 117 + (12 * packfactor) bytes per transaction. So the number of partial checkpoints will vary, depending on the checkpoint frequency, the power of the loading host, and the power of the Teradata target database.
Thus, an equation for the space is:
200 + 200 * each statement in the support environment + 400 * each BEGIN/END LOAD + 200 * each statement issued as DML + 200 * the estimated number of checkpoints + (117 + (12 * packfactor)) * the number of partial checkpoints. A simplified version would be:
R = 200 + 200S + 400L + 200D + 200C + (117 + (12P))N,
where:
R = Required space for Teradata TPump log table
S = Each SQL statement issued through the support environment
L = Each BEGIN/END LOAD command pair
D = Each DML statement
C = Estimated number of checkpoints
P = Packfactor
N = Number of partial checkpoints