Hello,
I'm new to jsonb feature of postgres. I have PostgreSQL 13.2 running
locally in docker.
I've been playing a little bit with jsonb indexes described
https://www.postgresql.org/docs/13/datatype-json.html#JSON-INDEXING and
I'm not able make the GIN index work on 'tags'.
I was wondering what I'm doing wrong. There are steps what I've tried:
CREATE TABLE api (
jdoc jsonb
);
INSERT INTO api (jdoc)
VALUES ('{
"guid": "9c36adc1-7fb5-4d5b-83b4-90356a46061a",
"name": "Angela Barton",
"is_active": true,
"company": "Magnafone",
"address": "178 Howard Place, Gulf, Washington, 702",
"registered": "2009-11-07T08:53:22 +08:00",
"latitude": 19.793713,
"longitude": 86.513373,
"tags": [
"enim",
"aliquip",
"qui"
]
}');
CREATE INDEX idxgintags ON api USING GIN ((jdoc->'tags'));
EXPLAIN ANALYZE SELECT jdoc->'guid', jdoc->'name' FROM api WHERE jdoc ->
'tags' ? 'qui';
And the result is
Seq Scan on api (cost=0.00..1.02 rows=1 width=64) (actual
time=0.019..0.021 rows=1 loops=1)
Filter: ((jdoc -> 'tags'::text) ? 'qui'::text)
Planning Time: 0.115 ms
Execution Time: 0.047 ms
Do you know why Index Scan on idxgintag is not used?
Thank you,
Vlasta
