From pg_stat_all_tables, the number of disk blocks read from the TOAST table can be obtained.
From pg_stat_activity, the start time of the current query execution can be obtained.
From pg_stat_database, the number of errors that have occurred in the target database can be obtained.
From pg_statio_all_tables, the number of buffer hits for the target table can be obtained.
※This sample exam is different from those that appear in the actual OSS-DB Exam.
2025/05/30
A. The number of disk blocks read from the TOAST table is taken from the toast_blks_read column in pg_statio_all_tables.
B. The start time of the current query execution is taken from the query_start column of pg_stat_activity.
C. The number of error occurrences cannot be obtained from the standard statistics view.
D. The number of buffer hits for the target table is obtained from the heap_blks_hit column of pg_statio_all_tables.
Therefore, the correct answers are B and D.