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Diffstat (limited to 'contrib/pageinspect/README.pageinspect')
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diff --git a/contrib/pageinspect/README.pageinspect b/contrib/pageinspect/README.pageinspect deleted file mode 100644 index fc4991db64..0000000000 --- a/contrib/pageinspect/README.pageinspect +++ /dev/null @@ -1,94 +0,0 @@ -The functions in this module allow you to inspect the contents of data pages -at a low level, for debugging purposes. All of these functions may be used -only by superusers. - -1. Installation - - $ make - $ make install - $ psql -e -f /usr/local/pgsql/share/contrib/pageinspect.sql test - -2. Functions included: - - get_raw_page - ------------ - get_raw_page reads one block of the named table and returns a copy as a - bytea field. This allows a single time-consistent copy of the block to be - made. - - page_header - ----------- - page_header shows fields which are common to all PostgreSQL heap and index - pages. - - A page image obtained with get_raw_page should be passed as argument: - - regression=# SELECT * FROM page_header(get_raw_page('pg_class',0)); - lsn | tli | flags | lower | upper | special | pagesize | version | prune_xid - -----------+-----+-------+-------+-------+---------+----------+---------+----------- - 0/24A1B50 | 1 | 1 | 232 | 368 | 8192 | 8192 | 4 | 0 - (1 row) - - The returned columns correspond to the fields in the PageHeaderData struct. - See src/include/storage/bufpage.h for details. - - heap_page_items - --------------- - heap_page_items shows all line pointers on a heap page. For those line - pointers that are in use, tuple headers are also shown. All tuples are - shown, whether or not the tuples were visible to an MVCC snapshot at the - time the raw page was copied. - - A heap page image obtained with get_raw_page should be passed as argument: - - test=# SELECT * FROM heap_page_items(get_raw_page('pg_class',0)); - - See src/include/storage/itemid.h and src/include/access/htup.h for - explanations of the fields returned. - - bt_metap - -------- - bt_metap() returns information about a btree index's metapage: - - test=> SELECT * FROM bt_metap('pg_cast_oid_index'); - -[ RECORD 1 ]----- - magic | 340322 - version | 2 - root | 1 - level | 0 - fastroot | 1 - fastlevel | 0 - - bt_page_stats - ------------- - bt_page_stats() shows information about single btree pages: - - test=> SELECT * FROM bt_page_stats('pg_cast_oid_index', 1); - -[ RECORD 1 ]-+----- - blkno | 1 - type | l - live_items | 256 - dead_items | 0 - avg_item_size | 12 - page_size | 8192 - free_size | 4056 - btpo_prev | 0 - btpo_next | 0 - btpo | 0 - btpo_flags | 3 - - bt_page_items - ------------- - bt_page_items() returns information about specific items on btree pages: - - test=> SELECT * FROM bt_page_items('pg_cast_oid_index', 1); - itemoffset | ctid | itemlen | nulls | vars | data - ------------+---------+---------+-------+------+------------- - 1 | (0,1) | 12 | f | f | 23 27 00 00 - 2 | (0,2) | 12 | f | f | 24 27 00 00 - 3 | (0,3) | 12 | f | f | 25 27 00 00 - 4 | (0,4) | 12 | f | f | 26 27 00 00 - 5 | (0,5) | 12 | f | f | 27 27 00 00 - 6 | (0,6) | 12 | f | f | 28 27 00 00 - 7 | (0,7) | 12 | f | f | 29 27 00 00 - 8 | (0,8) | 12 | f | f | 2a 27 00 00 |