to be flexible about assignment casts without introducing ambiguity in
operator/function resolution. Introduce a well-defined promotion hierarchy
for numeric datatypes (int2->int4->int8->numeric->float4->float8).
Change make_const to initially label numeric literals as int4, int8, or
numeric (never float8 anymore).
Explicitly mark Func and RelabelType nodes to indicate whether they came
from a function call, explicit cast, or implicit cast; use this to do
reverse-listing more accurately and without so many heuristics.
Explicit casts to char, varchar, bit, varbit will truncate or pad without
raising an error (the pre-7.2 behavior), while assigning to a column without
any explicit cast will still raise an error for wrong-length data like 7.3.
This more nearly follows the SQL spec than 7.2 behavior (we should be
reporting a 'completion condition' in the explicit-cast cases, but we have
no mechanism for that, so just do silent truncation).
Fix some problems with enforcement of typmod for array elements;
it didn't work at all in 'UPDATE ... SET array[n] = foo', for example.
Provide a generalized array_length_coerce() function to replace the
specialized per-array-type functions that used to be needed (and were
missing for NUMERIC as well as all the datetime types).
Add missing conversions int8<->float4, text<->numeric, oid<->int8.
initdb forced.
pointed out by Barry Lind: UPDATE bigintcol = 10000000000 fails because
the constant is initially taken as float8. We really need a better way,
but it's not gonna happen for 7.3.
Also, remove int4reltime() function, which is redundant with the
existing binary-compatibility coercion path from int4 to reltime,
and probably has been unreachable code for a long while.
extension to create binary compatible casts. Includes dependency tracking
as well.
pg_proc.proimplicit is now defunct, but will be removed in a separate
commit.
pg_dump provides a migration path from the previous scheme to declare
casts. Dumping binary compatible casts is currently impossible, though.
Tom Lane
Bruce Momjian
Peter Eisentraut