DBCC PAGE equivalent in Postgres

In SQL Server you could check specific index information using the DBCC PAGE command. Is there anything similar in postgres?

And if there isn't, how would you get the same info then? This is simply for research purposes.

This command returns this:

Page @0x00000004ED67A000

m_pageId = (1:299)                  m_headerVersion = 1                 m_type = 1
m_typeFlagBits = 0x0                m_level = 0                         m_flagBits = 0x4
m_objId (AllocUnitId.idObj) = 121   m_indexId (AllocUnitId.idInd) = 256
Metadata: AllocUnitId = 72057594045857792
Metadata: PartitionId = 72057594040614912                                Metadata: IndexId = 1
Metadata: ObjectId = 99             m_prevPage = (1:297)                m_nextPage = (1:300)
pminlen = 4008                      m_slotCnt = 2                       m_freeCnt = 70
m_freeData = 8118                   m_reservedCnt = 0                   m_lsn = (35:184:44)
m_xactReserved = 0                  m_xdesId = (0:0)                    m_ghostRecCnt = 0
m_tornBits = 0                      DB Frag ID = 1

Allocation Status

GAM (1:2) = ALLOCATED               SGAM (1:3) = ALLOCATED 
PFS (1:1) = 0x60 MIXED_EXT ALLOCATED   0_PCT_FULL                        DIFF (1:6) = CHANGED 
ML (1:7) = NOT MIN_LOGGED

Slot 0 Offset 0x60 Length 4011

You can

CREATE EXTENSION pageinspect;

Then you can use the function

SELECT * FROM bt_page_stats('indexname' , 42);

to get some information about block 42 of the index: the number of live and dead entries, the amount of free space and the pointers to the left and right sibling (btpo_prev and btpo_next) and the type (root, intermediate or leaf).

StackExchange Database Administrators Q#252483, answer score: 2