__gp_aoseg_history(regclass)
This function returns metadata information contained in the append-optimized table's on-disk segment file.
It displays all different versions (heap tuples) of the aoseg meta-information.
The data is complex, but users with a deep understanding of the system may find it useful for debugging.
The input argument is the name or the OID of an append-optimized table.
| Column | Description |
|---|---|
gp_tid |
The ID of the tuple |
gp_xmin |
The ID of the earliest transaction |
gp_xmin_status |
Status of the |
gp_xmin_commit_distrib_id |
The commit distribution ID of the |
gp_xmax |
The ID of the latest transaction |
gp_xmax_status |
The status of the latest transaction |
gp_xmax_commit_distrib_id |
The commit distribution ID of the |
gp_command_id |
The ID of the query command |
gp_infomask |
A bitmap containing state information |
gp_update_tid |
The ID of the newer tuple if the row is updated |
gp_visibility |
The tuple visibility status |
segno |
The number of the segment in the segment file |
tupcount |
The number of tuples, including hidden tuples |
eof |
The effective end of file for the segment |
eof_uncompressed |
The end of file for the segment if data were uncompressed |
modcount |
A count of data modifications |
formatversion |
The storage format version of the append-only segment file |
state |
The status of the segment |