pgsql: Optimize get_jsonb_path_all avoiding an iterator

Optimize get_jsonb_path_all avoiding an iterator

Instead of creating an iterator object at each step down the JSONB
object/array, we can just just examine its object/array flags, which is
faster.  Also, use the recently introduced JsonbValueAsText instead of
open-coding the same thing, for code simplicity.

Author: Nikita Glukhov
Discussion: https://postgr.es/m/7c417f90-f95f-247e-ba63-d95e39c0ad14@postgrespro.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dbb9aeda9959d8a8f463e841b69dfa04afc67a3a

Modified Files
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src/backend/utils/adt/jsonfuncs.c | 33 ++++++++++-----------------------
1 file changed, 10 insertions(+), 23 deletions(-)