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Repair indexed bytea like operations, and related selectivity

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functionality. Per bug report by Alvar Freude:
http://archives.postgresql.org/pgsql-bugs/2003-12/msg00022.php
This commit is contained in:
Joe Conway 2003-12-07 04:14:10 +00:00
parent 7bb11a93e1
commit 53e7c1363a
1 changed files with 87 additions and 24 deletions
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111
src/backend/utils/adt/selfuncs.c
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@ -15,7 +15,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.149 2003/11/29 19:51:59 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.150 2003/12/07 04:14:10 joe Exp $
*
*-------------------------------------------------------------------------
*/
@ -184,6 +184,7 @@ static Selectivity prefix_selectivity(Query *root, Var *var,
static Selectivity pattern_selectivity(Const *patt, Pattern_Type ptype);
static Datum string_to_datum(const char *str, Oid datatype);
static Const *string_to_const(const char *str, Oid datatype);
static Const *string_to_bytea_const(const char *str, size_t str_len);
/*
@ -3135,20 +3136,31 @@ like_fixed_prefix(Const *patt_const, bool case_insensitive,
}
else
{
patt = DatumGetCString(DirectFunctionCall1(byteaout, patt_const->constvalue));
pattlen = toast_raw_datum_size(patt_const->constvalue) - VARHDRSZ;
bytea *bstr = DatumGetByteaP(patt_const->constvalue);
pattlen = VARSIZE(bstr) - VARHDRSZ;
if (pattlen > 0)
{
patt = (char *) palloc(pattlen);
memcpy(patt, VARDATA(bstr), pattlen);
}
else
patt = NULL;
if ((Pointer) bstr != DatumGetPointer(patt_const->constvalue))
pfree(bstr);
}
match = palloc(pattlen + 1);
match_pos = 0;
for (pos = 0; pos < pattlen; pos++)
{
/* % and _ are wildcard characters in LIKE */
if (patt[pos] == '%' ||
patt[pos] == '_')
break;
/* Backslash quotes the next character */
/* Backslash escapes the next character */
if (patt[pos] == '\\')
{
pos++;
@ -3174,10 +3186,19 @@ like_fixed_prefix(Const *patt_const, bool case_insensitive,
match[match_pos] = '\0';
rest = &patt[pos];
*prefix_const = string_to_const(match, typeid);
*rest_const = string_to_const(rest, typeid);
if (typeid != BYTEAOID)
{
*prefix_const = string_to_const(match, typeid);
*rest_const = string_to_const(rest, typeid);
}
else
{
*prefix_const = string_to_bytea_const(match, match_pos);
*rest_const = string_to_bytea_const(rest, pattlen - pos);
}
pfree(patt);
if (patt != NULL)
pfree(patt);
pfree(match);
/* in LIKE, an empty pattern is an exact match! */
@ -3500,9 +3521,22 @@ like_selectivity(Const *patt_const, bool case_insensitive)
}
else
{
patt = DatumGetCString(DirectFunctionCall1(byteaout, patt_const->constvalue));
pattlen = toast_raw_datum_size(patt_const->constvalue) - VARHDRSZ;
bytea *bstr = DatumGetByteaP(patt_const->constvalue);
pattlen = VARSIZE(bstr) - VARHDRSZ;
if (pattlen > 0)
{
patt = (char *) palloc(pattlen);
memcpy(patt, VARDATA(bstr), pattlen);
}
else
patt = NULL;
if ((Pointer) bstr != DatumGetPointer(patt_const->constvalue))
pfree(bstr);
}
/* patt should never be NULL in practice */
Assert(patt != NULL);
/* Skip any leading %; it's already factored into initial sel */
start = (*patt == '%') ? 1 : 0;
@ -3693,8 +3727,8 @@ pattern_selectivity(Const *patt, Pattern_Type ptype)
/*
* Try to generate a string greater than the given string or any
* string it is a prefix of. If successful, return a palloc'd string;
* else return NULL.
* string it is a prefix of. If successful, return a palloc'd string
* in the form of a Const pointer; else return NULL.
*
* The key requirement here is that given a prefix string, say "foo",
* we must be able to generate another string "fop" that is greater
@ -3712,27 +3746,38 @@ Const *
make_greater_string(const Const *str_const)
{
Oid datatype = str_const->consttype;
char *str;
char *workstr;
int len;
/* Get the string and a modifiable copy */
if (datatype == NAMEOID)
{
str = DatumGetCString(DirectFunctionCall1(nameout, str_const->constvalue));
len = strlen(str);
workstr = DatumGetCString(DirectFunctionCall1(nameout,
str_const->constvalue));
len = strlen(workstr);
}
else if (datatype == BYTEAOID)
{
str = DatumGetCString(DirectFunctionCall1(byteaout, str_const->constvalue));
len = toast_raw_datum_size(str_const->constvalue) - VARHDRSZ;
bytea *bstr = DatumGetByteaP(str_const->constvalue);
len = VARSIZE(bstr) - VARHDRSZ;
if (len > 0)
{
workstr = (char *) palloc(len);
memcpy(workstr, VARDATA(bstr), len);
}
else
workstr = NULL;
if ((Pointer) bstr != DatumGetPointer(str_const->constvalue))
pfree(bstr);
}
else
{
str = DatumGetCString(DirectFunctionCall1(textout, str_const->constvalue));
len = strlen(str);
workstr = DatumGetCString(DirectFunctionCall1(textout,
str_const->constvalue));
len = strlen(workstr);
}
workstr = pstrdup(str);
while (len > 0)
{
@ -3747,9 +3792,11 @@ make_greater_string(const Const *str_const)
Const *workstr_const;
(*lastchar)++;
workstr_const = string_to_const(workstr, datatype);
if (datatype != BYTEAOID)
workstr_const = string_to_const(workstr, datatype);
else
workstr_const = string_to_bytea_const(workstr, len);
pfree(str);
pfree(workstr);
return workstr_const;
}
@ -3771,8 +3818,8 @@ make_greater_string(const Const *str_const)
}
/* Failed... */
pfree(str);
pfree(workstr);
if (workstr != NULL)
pfree(workstr);
return (Const *) NULL;
}
@ -3811,6 +3858,22 @@ string_to_const(const char *str, Oid datatype)
conval, false, false);
}
/*
* Generate a Const node of bytea type from a binary C string and a length.
*/
static Const *
string_to_bytea_const(const char *str, size_t str_len)
{
bytea *bstr = palloc(VARHDRSZ + str_len);
Datum conval;
memcpy(VARDATA(bstr), str, str_len);
VARATT_SIZEP(bstr) = VARHDRSZ + str_len;
conval = PointerGetDatum(bstr);
return makeConst(BYTEAOID, -1, conval, false, false);
}
/*-------------------------------------------------------------------------
*
* Index cost estimation functions