Thread: pgsql: Cache by-reference missing values in a long lived context
Cache by-reference missing values in a long lived context Attribute missing values might be needed past the lifetime of the tuple descriptors from which they are extracted. To avoid possibly using pointers for by-reference values which might thus be left dangling, we cache a datumCopy'd version of the datum in the TopMemoryContext. Since we first search for the value this only needs to be done once per session for any such value. Original complaint from Tom Lane, idea for mitigation by Andrew Dunstan, tweaked by Tom Lane. Backpatch to version 11 where missing values were introduced. Discussion: https://postgr.es/m/1306569.1687978174@sss.pgh.pa.us Branch ------ REL_15_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/75f323aa1c1ec88f9781cb6d9307e42b820b26f0 Modified Files -------------- src/backend/access/common/heaptuple.c | 90 ++++++++++++++++++++++++++++++++++- src/tools/pgindent/typedefs.list | 1 + 2 files changed, 90 insertions(+), 1 deletion(-)