PG_RELFILENODE_SIZE

databaseid

OID

OID of the database that the physical file belongs to If a system catalog is shared across databases, its value is 0.

tablespaceid

OID

Tablespace OID of the physical file

relfilenode

OID

Serial number of the physical file

backendid

Integer

ID of the background thread that creates the physical file. Generally, the value is -1.

type

Integer

Type of the physical file.

• The value 0 indicates a data file.
• The value 1 indicates an FSM file.
• The value 2 indicates a VM file.
• The value 3 indicates a BCM file.
• If the value greater than 4 indicates the total size of the data file and BCM file of the column in a column-store table.

filesize

Bigint

Size of the physical file, in bytes.