Hackers,
The documentation for pg_locks says that, for BIGINT advisory locks:
> A bigint key is displayed with its high-order half in the classid column, its low-order half in the objid column
I was in need of knowing what the bigint is that is waiting on a lock, and Andrew Dunstan was kind enough to help me
outwith that. Since other folks might also need it, here’s a doc patch.
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
new file mode 100644
index 9564e01..de1c266
*** a/doc/src/sgml/catalogs.sgml
--- b/doc/src/sgml/catalogs.sgml
***************
*** 7313,7319 **** A <type>bigint</type> key is displayed with its high-order half in the <structfield>classid</>
column,its low-order half in the <structfield>objid</> column, and <structfield>objsubid</> equal
! to 1. Integer keys are displayed with the first key in the <structfield>classid</> column, the second key in
the<structfield>objid</> column, and <structfield>objsubid</> equal to 2. The actual meaning of the keys is up
tothe user. Advisory locks are local to each database,
--- 7313,7322 ---- A <type>bigint</type> key is displayed with its high-order half in the <structfield>classid</>
column,its low-order half in the <structfield>objid</> column, and <structfield>objsubid</> equal
! to 1. The original <type>bigint</type> value can be reassembled with the
! expression <literal>(classid::int::bit(64) << 32 |
! objid::int::bit(64))::bigint</literal>. Integer keys are displayed with the
! first key in the <structfield>classid</> column, the second key in the <structfield>objid</> column, and
<structfield>objsubid</>equal to 2. The actual meaning of the keys is up to the user. Advisory locks are local to
eachdatabase,
Best,
DAvid
