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Extend pg_cast castimplicit column to a three-way value; this allows us

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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.
This commit is contained in:
Tom Lane
2002-09-18 21:35:25 +00:00
parent cc70ba2e4d
commit b26dfb9522
70 changed files with 1642 additions and 1528 deletions
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130
src/backend/utils/adt/varchar.c
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@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/adt/varchar.c,v 1.94 2002/09/04 20:31:29 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/adt/varchar.c,v 1.95 2002/09/18 21:35:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -165,21 +165,28 @@ bpcharout(PG_FUNCTION_ARGS)
/*
* Converts a CHARACTER type to the specified size. maxlen is the new
* declared length plus VARHDRSZ bytes. Truncation
* rules see bpcharin() above.
* Converts a CHARACTER type to the specified size.
*
* maxlen is the typmod, ie, declared length plus VARHDRSZ bytes.
* isExplicit is true if this is for an explicit cast to char(N).
*
* Truncation rules: for an explicit cast, silently truncate to the given
* length; for an implicit cast, raise error unless extra characters are
* all spaces. (This is sort-of per SQL: the spec would actually have us
* raise a "completion condition" for the explicit cast case, but Postgres
* hasn't got such a concept.)
*/
Datum
bpchar(PG_FUNCTION_ARGS)
{
BpChar *source = PG_GETARG_BPCHAR_P(0);
int32 maxlen = PG_GETARG_INT32(1);
bool isExplicit = PG_GETARG_BOOL(2);
BpChar *result;
int32 len;
char *r;
char *s;
int i;
int charlen; /* number of charcters in the input string
* + VARHDRSZ */
@ -188,7 +195,7 @@ bpchar(PG_FUNCTION_ARGS)
charlen = pg_mbstrlen_with_len(VARDATA(source), len - VARHDRSZ) + VARHDRSZ;
/* No work if typmod is invalid or supplied data matches it already */
if (maxlen < (int32) VARHDRSZ || len == maxlen)
if (maxlen < (int32) VARHDRSZ || charlen == maxlen)
PG_RETURN_BPCHAR_P(source);
if (charlen > maxlen)
@ -199,10 +206,13 @@ bpchar(PG_FUNCTION_ARGS)
maxmblen = pg_mbcharcliplen(VARDATA(source), len - VARHDRSZ,
maxlen - VARHDRSZ) + VARHDRSZ;
for (i = maxmblen - VARHDRSZ; i < len - VARHDRSZ; i++)
if (*(VARDATA(source) + i) != ' ')
elog(ERROR, "value too long for type character(%d)",
maxlen - VARHDRSZ);
if (!isExplicit)
{
for (i = maxmblen - VARHDRSZ; i < len - VARHDRSZ; i++)
if (*(VARDATA(source) + i) != ' ')
elog(ERROR, "value too long for type character(%d)",
maxlen - VARHDRSZ);
}
len = maxmblen;
@ -238,37 +248,6 @@ bpchar(PG_FUNCTION_ARGS)
}
/* _bpchar()
* Converts an array of char() elements to a specific internal length.
* len is the length specified in () plus VARHDRSZ bytes.
*/
Datum
_bpchar(PG_FUNCTION_ARGS)
{
ArrayType *v = PG_GETARG_ARRAYTYPE_P(0);
int32 len = PG_GETARG_INT32(1);
FunctionCallInfoData locfcinfo;
/*
* Since bpchar() is a built-in function, we should only need to look
* it up once per run.
*/
static FmgrInfo bpchar_finfo;
if (bpchar_finfo.fn_oid == InvalidOid)
fmgr_info_cxt(F_BPCHAR, &bpchar_finfo, TopMemoryContext);
MemSet(&locfcinfo, 0, sizeof(locfcinfo));
locfcinfo.flinfo = &bpchar_finfo;
locfcinfo.nargs = 2;
/* We assume we are "strict" and need not worry about null inputs */
locfcinfo.arg[0] = PointerGetDatum(v);
locfcinfo.arg[1] = Int32GetDatum(len);
return array_map(&locfcinfo, BPCHAROID, BPCHAROID);
}
/* char_bpchar()
* Convert char to bpchar(1).
*/
@ -354,9 +333,9 @@ name_bpchar(PG_FUNCTION_ARGS)
* Note that atttypmod is regarded as the number of characters, which
* is not necessarily the same as the number of bytes.
*
* If the C string is too long,
* raise an error, unless the extra characters are spaces, in which
* case they're truncated. (per SQL) */
* If the C string is too long, raise an error, unless the extra characters
* are spaces, in which case they're truncated. (per SQL)
*/
Datum
varcharin(PG_FUNCTION_ARGS)
{
@ -428,17 +407,26 @@ varcharout(PG_FUNCTION_ARGS)
/*
* Converts a VARCHAR type to the specified size. maxlen is the new
* declared length plus VARHDRSZ bytes. Truncation
* rules see varcharin() above.
* Converts a VARCHAR type to the specified size.
*
* maxlen is the typmod, ie, declared length plus VARHDRSZ bytes.
* isExplicit is true if this is for an explicit cast to varchar(N).
*
* Truncation rules: for an explicit cast, silently truncate to the given
* length; for an implicit cast, raise error unless extra characters are
* all spaces. (This is sort-of per SQL: the spec would actually have us
* raise a "completion condition" for the explicit cast case, but Postgres
* hasn't got such a concept.)
*/
Datum
varchar(PG_FUNCTION_ARGS)
{
VarChar *source = PG_GETARG_VARCHAR_P(0);
int32 maxlen = PG_GETARG_INT32(1);
bool isExplicit = PG_GETARG_BOOL(2);
VarChar *result;
int32 len;
size_t maxmblen;
int i;
len = VARSIZE(source);
@ -448,21 +436,19 @@ varchar(PG_FUNCTION_ARGS)
/* only reach here if string is too long... */
/* truncate multibyte string preserving multibyte boundary */
maxmblen = pg_mbcharcliplen(VARDATA(source), len - VARHDRSZ,
maxlen - VARHDRSZ);
if (!isExplicit)
{
size_t maxmblen;
/* truncate multibyte string preserving multibyte boundary */
maxmblen = pg_mbcharcliplen(VARDATA(source), len - VARHDRSZ,
maxlen - VARHDRSZ) + VARHDRSZ;
for (i = maxmblen - VARHDRSZ; i < len - VARHDRSZ; i++)
for (i = maxmblen; i < len - VARHDRSZ; i++)
if (*(VARDATA(source) + i) != ' ')
elog(ERROR, "value too long for type character varying(%d)",
maxlen - VARHDRSZ);
len = maxmblen;
}
len = maxmblen + VARHDRSZ;
result = palloc(len);
VARATT_SIZEP(result) = len;
memcpy(VARDATA(result), VARDATA(source), len - VARHDRSZ);
@ -471,38 +457,6 @@ varchar(PG_FUNCTION_ARGS)
}
/* _varchar()
* Converts an array of varchar() elements to the specified size.
* len is the length specified in () plus VARHDRSZ bytes.
*/
Datum
_varchar(PG_FUNCTION_ARGS)
{
ArrayType *v = PG_GETARG_ARRAYTYPE_P(0);
int32 len = PG_GETARG_INT32(1);
FunctionCallInfoData locfcinfo;
/*
* Since varchar() is a built-in function, we should only need to look
* it up once per run.
*/
static FmgrInfo varchar_finfo;
if (varchar_finfo.fn_oid == InvalidOid)
fmgr_info_cxt(F_VARCHAR, &varchar_finfo, TopMemoryContext);
MemSet(&locfcinfo, 0, sizeof(locfcinfo));
locfcinfo.flinfo = &varchar_finfo;
locfcinfo.nargs = 2;
/* We assume we are "strict" and need not worry about null inputs */
locfcinfo.arg[0] = PointerGetDatum(v);
locfcinfo.arg[1] = Int32GetDatum(len);
return array_map(&locfcinfo, VARCHAROID, VARCHAROID);
}
/*****************************************************************************
* Exported functions
*****************************************************************************/