SQL/JSON revisited

Amit Langote <amitlangote09@gmail.com>

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From: Amit Langote <amitlangote09@gmail.com>

To: PostgreSQL-development <pgsql-hackers@postgresql.org>

Cc: Andrew Dunstan <andrew@dunslane.net>

Date: 2022-12-28T07:28:29Z

Lists: pgsql-hackers

Attachments

v1-0007-JSON_TABLE.patch (application/octet-stream) patch v1-0007
v1-0010-Claim-SQL-standard-compliance-for-SQL-JSON-featur.patch (application/octet-stream) patch v1-0010
v1-0009-Documentation-for-SQL-JSON-features.patch (application/octet-stream) patch v1-0009
v1-0008-PLAN-clauses-for-JSON_TABLE.patch (application/octet-stream) patch v1-0008
v1-0006-RETURNING-clause-for-JSON-and-JSON_SCALAR.patch (application/octet-stream) patch v1-0006
v1-0005-SQL-JSON-functions.patch (application/octet-stream) patch v1-0005
v1-0004-SQL-JSON-query-functions.patch (application/octet-stream) patch v1-0004
v1-0001-Common-SQL-JSON-clauses.patch (application/octet-stream) patch v1-0001
v1-0003-IS-JSON-predicate.patch (application/octet-stream) patch v1-0003
v1-0002-SQL-JSON-constructors.patch (application/octet-stream) patch v1-0002

Hi,

Rebased the SQL/JSON patches over the latest HEAD.  I've decided to
keep the same division of code into individual commits as that
mentioned in the revert commit 2f2b18bd3f, squashing fixup commits in
that list into the appropriate feature commits.

The main difference from the patches as they were committed into v15
is that JsonExpr evaluation no longer needs to use sub-transactions,
thanks to the work done recently to handle type errors softly.  I've
made the new code pass an ErrorSaveContext into the type-conversion
related functions as needed and also added an ExecEvalExprSafe() to
evaluate sub-expressions of JsonExpr that might contain expressions
that call type-conversion functions, such as CoerceViaIO contained in
JsonCoercion nodes.  ExecExprEvalSafe() is based on one of the patches
that Nikita Glukhov had submitted in a previous discussion about
redesigning SQL/JSON expression evaluation [1].  Though, I think that
new interface will become unnecessary after I have finished rebasing
my patches to remove subsidiary ExprStates of JsonExprState that we
had also discussed back in [2].

Adding this to January CF.

-- 
Thanks, Amit Langote
EDB: http://www.enterprisedb.com

[1] https://www.postgresql.org/message-id/c3b315b6-1e9f-6aa4-8708-daa19cf3f1a3%40postgrespro.ru
[2] https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de

Commits

Add SQL/JSON query functions
- 6185c9737cf4 17.0 landed
Add soft error handling to some expression nodes
- aaaf9449ec6b 17.0 landed
Adjust populate_record_field() to handle errors softly
- 1edb3b491bee 17.0 landed
Refactor code used by jsonpath executor to fetch variables
- faa2b953ba3b 17.0 landed
Code review for recent SQL/JSON commits
- 71bfd1543f8b 16.0 landed
Fix inconsistencies and style issues in new SQL/JSON code
- 60966f56c3e4 16.0 landed
Don't install postmaster symlink anymore
- 37e267335068 16.0 cited
Revert SQL/JSON features
- 2f2b18bd3f55 16.0 cited
Doc: standardize markup a bit more.
- 47046763c3ed 13.0 cited