diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2020-09-17 19:38:05 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2020-09-17 19:38:05 -0400 |
| commit | 1ed6b895634ce0dc5fd4bd040e87252b32182cba (patch) | |
| tree | d0f22d227e7df8ca5139baf4eba578de052f6a82 /src/backend/commands/operatorcmds.c | |
| parent | 76f412ab310554acb970a0b73c8d1f37f35548c6 (diff) | |
| download | postgresql-1ed6b895634ce0dc5fd4bd040e87252b32182cba.tar.gz postgresql-1ed6b895634ce0dc5fd4bd040e87252b32182cba.zip | |
Remove support for postfix (right-unary) operators.
This feature has been a thorn in our sides for a long time, causing
many grammatical ambiguity problems. It doesn't seem worth the
pain to continue to support it, so remove it.
There are some follow-on improvements we can make in the grammar,
but this commit only removes the bare minimum number of productions,
plus assorted backend support code.
Note that pg_dump and psql continue to have full support, since
they may be used against older servers. However, pg_dump warns
about postfix operators. There is also a check in pg_upgrade.
Documentation-wise, I (tgl) largely removed the "left unary"
terminology in favor of saying "prefix operator", which is
a more standard and IMO less confusing term.
I included a catversion bump, although no initial catalog data
changes here, to mark the boundary at which oprkind = 'r'
stopped being valid in pg_operator.
Mark Dilger, based on work by myself and Robert Haas;
review by John Naylor
Discussion: https://postgr.es/m/38ca86db-42ab-9b48-2902-337a0d6b8311@2ndquadrant.com
Diffstat (limited to 'src/backend/commands/operatorcmds.c')
| -rw-r--r-- | src/backend/commands/operatorcmds.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/src/backend/commands/operatorcmds.c b/src/backend/commands/operatorcmds.c index bf23937849c..a791e99092d 100644 --- a/src/backend/commands/operatorcmds.c +++ b/src/backend/commands/operatorcmds.c @@ -168,10 +168,22 @@ DefineOperator(List *names, List *parameters) if (typeName2) typeId2 = typenameTypeId(NULL, typeName2); + /* + * If only the right argument is missing, the user is likely trying to + * create a postfix operator, so give them a hint about why that does not + * work. But if both arguments are missing, do not mention postfix + * operators, as the user most likely simply neglected to mention the + * arguments. + */ if (!OidIsValid(typeId1) && !OidIsValid(typeId2)) ereport(ERROR, (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION), - errmsg("at least one of leftarg or rightarg must be specified"))); + errmsg("operator argument types must be specified"))); + if (!OidIsValid(typeId2)) + ereport(ERROR, + (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION), + errmsg("operator right argument type must be specified"), + errdetail("Postfix operators are not supported."))); if (typeName1) { |