Re: Set query_id for query contained in utility statement

hi. Anthonin
please check attached v9-0001, v9-0002, v9-003.

v9-0001-Better-error-reporting-from-extension-scripts-Was.patch
same as v4-0001-Improve-parser-s-reporting-of-statement-start-loc.patch in [1]

v9-0002-Add-tests-covering-pgss-nested-queries.patch same as
v8-0001-Add-tests-covering-pgss-nested-queries.patch in [2]
which is your work.

v9-0003-Track-location-in-nested-explain-statement.patch
is the main change I made based on your patch.

in [3] I mentioned adding "ParseLoc location" to ExplainStmt, then you
found some problems at [4] with multi statements,
now I found a way to resolve it.
I also add "ParseLoc location;" to typedef struct CopyStmt.
copy (select 1) to stdout;
I tested my change can tracking
beginning location and length of the nested query ("select 1")

I didn't touch other nested queries cases yet, so far only ExplainStmt
and CopyStmt1
IMHO, it's more neat than your patches.
Can you give it a try?

[1] https://www.postgresql.org/message-id/2245576.1728418678%40sss.pgh.pa.us
[2] https://www.postgresql.org/message-id/CAO6_XqqMYOxJmHJWCKjP44T9AsW0MmKV87XUYCP3R9JZvYcVaw%40mail.gmail.com
[3] https://www.postgresql.org/message-id/CACJufxEXSfk4o2jHDhf50fOY6WC%2BdFQke2gmpcz%2BEHVUsmEptg%40mail.gmail.com
[4] https://www.postgresql.org/message-id/CAO6_Xqrjr_1Ss0bRe5VFm6OsUwX2nuN_VhbhYj0LFP3acoaaWw%40mail.gmail.com

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SELECT pg_stat_statements_reset() IS NOT NULL AS t;
explain(verbose) SELECT 1, 2, 3;
explain(verbose) (SELECT 1, 2, 3);
SELECT toplevel, calls, query FROM pg_stat_statements ORDER BY query
COLLATE "C", toplevel;
will have 2 calls for "SELECT $1, $2, $3"

SELECT pg_stat_statements_reset() IS NOT NULL AS t;
explain(verbose) (SELECT 1, 2, 3);
explain(verbose) SELECT 1, 2, 3;
SELECT toplevel, calls, query FROM pg_stat_statements ORDER BY query
COLLATE "C", toplevel;
will have 2 calls for " (SELECT $1, $2, $3)"
I think that's fine.