[Tcl-tdbc] tdbc::sqlite3, Sqlite amalgamation >= 3.14, and trace_v2

[Trevor D. (Twylite) <tw...@cr...>]

Hi,

I'm in the process of upgrading Sqlite3 in an application with an older 
(Tcl 8.6.2 circa 2014) runtime, and I've run into an issue with 
tdbc::sqlite3. What I'm seeing is that `nextlist` always gives an empty row.

Digging through the source (sqlite3-1.0.1.tm) it looks like the problem 
is that `${-db} trace [namespace code {my RecordStatement}]` is not 
firing, so `-needcolumns` never gets set, `columns` never gets added to 
`-results`, and eventually `nextlist` has no columns to iterate over so 
it returns an empty list. The root cause appears to be that shortly 
after sqlite_trace_v2() was added in Sqlite 3.14, the DbTraceHandler 
used by the old sqlite_trace() was marked deprecated (see 
https://sqlite.org/src/annotate?filename=src/tclsqlite.c&checkin=trunk), 
and thus `${-db} trace` is no longer supported by the Sqlite 
Amalgamation. According to 
https://core.tcl-lang.org/tdbcsqlite3/finfo?name=library/tdbcsqlite3.tcl 
the latest tdbc::sqlite3 still uses `${-db} trace` instead of 
`trace_v2`. I don't see any related tickets at 
https://core.tcl-lang.org/tdbcsqlite3/ticket.

Have I missed something here, or is everyone (who is using 
tdbc::sqlite3) using it with an older Sqlite (< 3.14) or a custom (not 
Amalgamation) build?

Kind regards,
Trevor