"David G. Johnston" <david.g.johnston@xxxxxxxxx> writes: > On Tue, Apr 30, 2024 at 11:57 AM Gaurav Pant <gauravpant145@xxxxxxxxx> > wrote: >> I wanted to know if there is any such system table that we can use to >> identify and map the fields containing large objects and the respective >> tables and if it is not already there, do we have any plans to incorporate >> the same in pg_class like we have for pg_toast? > Large Objects are nothing like TOAST. There is no system level association > between large objects and tables. Sure, the DBA can choose to store a > large object OID in a table, but how you'd go about figuring out which > columns contain those is going to be installation specific. Yeah. You might want to look at contrib/vacuumlo, but realize that that's fairly heuristic. > Though > hopefully they used a bigint data type and maybe added "oid" to the column > name...I suppose it would be interesting if one could define a FK on a > table and point it at pg_largeobject_metadata but that I suspect would be > the extent to which we'd do something along the lines of your request. That would solve the opposite problem, of preventing a column from containing any OIDs that *weren't* large object OIDs. Given that recording a large object OID elsewhere in the database is purely an application decision, I don't think there's a reasonable way for the system to track it. regards, tom lane
