Fix: faster wildcard queries for JSONB fields

[psrok1]

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• I've read the contributing guideline.
• I've tested my changes by building and running the project, and testing changed functionality (if applicable)
• I've added automated tests for my change (if applicable, optional)
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What is the current behaviour?

JSONB wildcard queries are very slow because there is no supported JSONB "LIKE" operator that works with current implementation of GIN index. In the same time, LIKE on jsonb_path_query function result is very expensive.

So queries like:

cfg:"*/content/*"

may take minutes, especially when matching rows are really far in config table, which is far more than usual request timeout setting.

What is the new behaviour?

Configs are too long to be indexed by simple btree, but we found that simple object.cfg::text LIKE "%...%" works much faster even if it performs a full table scan. It's not exactly what we want if we use key predicate (cfg.urls:*/content/*) so it's still combined with the original jsonb_path_query-based solution with hope that PostgreSQL will use simple LIKE to pre-filter the rows before using function-based query. On our database data it usually does.

In future PRs I plan to optimize it further to avoid full scan at all.

Test plan

Closing issues