database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-08 11:42:09 +03:00
Code Activity

Remove dead encoding-conversion functions.

Browse Source 
The code for conversions SQL_ASCII <-> MULE_INTERNAL and
SQL_ASCII <-> UTF8 was unreachable, because we long ago changed
the wrapper functions pg_do_encoding_conversion() et al so that
they have hard-wired behaviors for conversions involving SQL_ASCII.
(At least some of those fast paths date back to 2002, though it
looks like we may not have been totally consistent about this until
later.)  Given the lack of complaints, nobody is dissatisfied with
this state of affairs.  Hence, let's just remove the unreachable code.

Also, change CREATE CONVERSION so that it rejects attempts to
define such conversions.  Since we consider that SQL_ASCII represents
lack of knowledge about the encoding in use, such a conversion would
be semantically dubious even if it were reachable.

Adjust a couple of regression test cases that had randomly decided
to rely on these conversion functions rather than any other ones.

Discussion: https://postgr.es/m/41163.1559156593@sss.pgh.pa.us
This commit is contained in:
Tom Lane
2019-07-05 14:17:27 -04:00
parent ef777cb093
commit 0ab1a2e39b
18 changed files with 44 additions and 269 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
src/backend/commands/conversioncmds.c
View File

@ -72,6 +72,18 @@ CreateConversionCommand(CreateConversionStmt *stmt)
errmsg("destination encoding \"%s\" does not exist",
to_encoding_name)));
/*
* We consider conversions to or from SQL_ASCII to be meaningless. (If
* you wish to change this, note that pg_do_encoding_conversion() and its
* sister functions have hard-wired fast paths for any conversion in which
* the source or target encoding is SQL_ASCII, so that an encoding
* conversion function declared for such a case will never be used.)
*/
if (from_encoding == PG_SQL_ASCII || to_encoding == PG_SQL_ASCII)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("encoding conversion to or from \"SQL_ASCII\" is not supported")));
/*
* Check the existence of the conversion function. Function name could be
* a qualified name.