The following examples collect statistics on the system-derived PARTITION column for the table named table_1.
Even though you have specified sampled statistics for the second example, the system ignores it and uses a value of 100 percent because you cannot collect sampled statistics on a system-derived PARTITION column. See Teradata Vantage™ - SQL Data Definition Language Detailed Topics, B035-1184.
COLLECT STATISTICS ON table_1 COLUMN PARTITION; COLLECT STATISTICS USING SAMPLE table_1 COLUMN PARTITION;