GLOBAL_GS_SEG_SPC_EXTENTS

GLOBAL_GS_SEG_SPC_EXTENTS displays the information about used extents of all tablespaces on all nodes, which can only be executed on the CN. The output contains segment heads, fork heads, level-1 pages, data extents. Only an administrator can query the information.

**Table 1** GLOBAL_GS_SEG_SPC_EXTENTS
Name	Type	Description
node_name	text	Node name.
tablespace_name	name	Tablespace name.
file_id	integer	Data file ID.
bucketnode	integer	0 to 1023 indicate the bucket nodes of a hash bucket table. 1024 indicates the bucket node of a segment-page ordinary table. 1025 indicates the bucket node of a segment-page global temporary table. 1026 indicates the bucket node of a segment-page unlogged table. 1027 indicates the bucket node of a segment-page local temporary table.
forknum	integer	Fork type of a segment object. Value range: 0: main fork. 1: fsm fork. 2: vm fork.
block_id	bigint	Start page number of a data extent.
blocks	integer	Data extent size. The value can be 1, 8, 128, 1024, or 4096.
contents	text	Storage content of a data file. Value range: permanent: permanent. unlogged: no log. temporary: global temporary. temporary2: local temporary.
in_used	text	Specifies whether a resource has been allocated. The value can be Y or N.
mapblock_location	text	Position of the extension in the map block. The format is (page_id, offset).
head_file_id	integer	Segment header file ID.
head_block_id	bigint	Page number of the segment header.
usage_type	text	Extended usage type. The options are as follows: segment head: segment header. fork head: fork header. level1 page: level-1 page. data extent: data extents.
remain_flag	text	Specifies whether it is a residual extent after the SHRINK operation. The value can be Y or N.
special_data	integer	Special data section of the reverse pointer corresponding to an extent.
ipblock_location	text	Position of the extended reverse pointer. The format is (block_id, offset).