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Extend sortsupport for text to more opclasses. 

Have varlena.c expose an interface that allows the char(n), bytea, and
bpchar types to piggyback on a now-generalized SortSupport for text.
This pushes a little more knowledge of the bpchar/char(n) type into
varlena.c than might be preferred, but that seems like the approach
that creates least friction.  Also speed things up for index builds
that use text_pattern_ops or varchar_pattern_ops.

This patch does quite a bit of renaming, but it seems likely to be
worth it, so as to avoid future confusion about the fact that this code
is now more generally used than the old names might have suggested.

Peter Geoghegan, reviewed by Álvaro Herrera and Andreas Karlsson,
with small tweaks by me.
This commit is contained in:
Robert Haas 2016-02-03 14:17:35 -05:00
parent 24a26c9f54
commit b47b4dbf68
8 changed files with 336 additions and 136 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
doc/src/sgml/datatype.sgml
View File

@ -1140,8 +1140,7 @@ SELECT '52093.89'::money::numeric::float8;
advantages in some other database systems, there is no such advantage in
<productname>PostgreSQL</productname>; in fact
<type>character(<replaceable>n</>)</type> is usually the slowest of
the three because of its additional storage costs and slower
sorting. In most situations
the three because of its additional storage costs. In most situations
<type>text</type> or <type>character varying</type> should be used
instead.
</para>

57
src/backend/utils/adt/varchar.c
View File

@ -17,6 +17,7 @@
#include "access/hash.h"
#include "access/tuptoaster.h"
#include "catalog/pg_collation.h"
#include "libpq/pqformat.h"
#include "nodes/nodeFuncs.h"
#include "utils/array.h"
@ -649,14 +650,21 @@ varchartypmodout(PG_FUNCTION_ARGS)
*****************************************************************************/
/* "True" length (not counting trailing blanks) of a BpChar */
static int
static inline int
bcTruelen(BpChar *arg)
{
char *s = VARDATA_ANY(arg);
int i;
int len;
return bpchartruelen(VARDATA_ANY(arg), VARSIZE_ANY_EXHDR(arg));
}
len = VARSIZE_ANY_EXHDR(arg);
int
bpchartruelen(char *s, int len)
{
int i;
/*
* Note that we rely on the assumption that ' ' is a singleton unit on
* every supported multibyte server encoding.
*/
for (i = len - 1; i >= 0; i--)
{
if (s[i] != ' ')
@ -858,6 +866,23 @@ bpcharcmp(PG_FUNCTION_ARGS)
PG_RETURN_INT32(cmp);
}
Datum
bpchar_sortsupport(PG_FUNCTION_ARGS)
{
SortSupport ssup = (SortSupport) PG_GETARG_POINTER(0);
Oid collid = ssup->ssup_collation;
MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(ssup->ssup_cxt);
/* Use generic string SortSupport */
varstr_sortsupport(ssup, collid, true);
MemoryContextSwitchTo(oldcontext);
PG_RETURN_VOID();
}
Datum
bpchar_larger(PG_FUNCTION_ARGS)
{
@ -926,8 +951,9 @@ hashbpchar(PG_FUNCTION_ARGS)
/*
* The following operators support character-by-character comparison
* of bpchar datums, to allow building indexes suitable for LIKE clauses.
* Note that the regular bpchareq/bpcharne comparison operators are assumed
* to be compatible with these!
* Note that the regular bpchareq/bpcharne comparison operators, and
* regular support functions 1 and 2 with "C" collation are assumed to be
* compatible with these!
*/
static int
@ -1030,3 +1056,20 @@ btbpchar_pattern_cmp(PG_FUNCTION_ARGS)
PG_RETURN_INT32(result);
}
Datum
btbpchar_pattern_sortsupport(PG_FUNCTION_ARGS)
{
SortSupport ssup = (SortSupport) PG_GETARG_POINTER(0);
MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(ssup->ssup_cxt);
/* Use generic string SortSupport, forcing "C" collation */
varstr_sortsupport(ssup, C_COLLATION_OID, true);
MemoryContextSwitchTo(oldcontext);
PG_RETURN_VOID();
}

391
src/backend/utils/adt/varlena.c
View File

@ -40,6 +40,7 @@
int bytea_output = BYTEA_OUTPUT_HEX;
typedef struct varlena unknown;
typedef struct varlena string;
typedef struct
{
@ -67,13 +68,14 @@ typedef struct
int last_returned; /* Last comparison result (cache) */
bool cache_blob; /* Does buf2 contain strxfrm() blob, etc? */
bool collate_c;
bool bpchar; /* Sorting pbchar, not varchar/text/bytea? */
hyperLogLogState abbr_card; /* Abbreviated key cardinality state */
hyperLogLogState full_card; /* Full key cardinality state */
double prop_card; /* Required cardinality proportion */
#ifdef HAVE_LOCALE_T
pg_locale_t locale;
#endif
} TextSortSupport;
} StringSortSupport;
/*
* This should be large enough that most strings will fit, but small enough
@ -87,12 +89,15 @@ typedef struct
#define PG_GETARG_UNKNOWN_P_COPY(n) DatumGetUnknownPCopy(PG_GETARG_DATUM(n))
#define PG_RETURN_UNKNOWN_P(x) PG_RETURN_POINTER(x)
static void btsortsupport_worker(SortSupport ssup, Oid collid);
static int bttextfastcmp_c(Datum x, Datum y, SortSupport ssup);
static int bttextfastcmp_locale(Datum x, Datum y, SortSupport ssup);
static int bttextcmp_abbrev(Datum x, Datum y, SortSupport ssup);
static Datum bttext_abbrev_convert(Datum original, SortSupport ssup);
static bool bttext_abbrev_abort(int memtupcount, SortSupport ssup);
#define DatumGetStringP(X) ((string *) PG_DETOAST_DATUM(X))
#define DatumGetStringPP(X) ((string *) PG_DETOAST_DATUM_PACKED(X))
static int varstrfastcmp_c(Datum x, Datum y, SortSupport ssup);
static int bpcharfastcmp_c(Datum x, Datum y, SortSupport ssup);
static int varstrfastcmp_locale(Datum x, Datum y, SortSupport ssup);
static int varstrcmp_abbrev(Datum x, Datum y, SortSupport ssup);
static Datum varstr_abbrev_convert(Datum original, SortSupport ssup);
static bool varstr_abbrev_abort(int memtupcount, SortSupport ssup);
static int32 text_length(Datum str);
static text *text_catenate(text *t1, text *t2);
static text *text_substring(Datum str,
@ -1738,19 +1743,30 @@ bttextsortsupport(PG_FUNCTION_ARGS)
oldcontext = MemoryContextSwitchTo(ssup->ssup_cxt);
btsortsupport_worker(ssup, collid);
/* Use generic string SortSupport */
varstr_sortsupport(ssup, collid, false);
MemoryContextSwitchTo(oldcontext);
PG_RETURN_VOID();
}
static void
btsortsupport_worker(SortSupport ssup, Oid collid)
/*
* Generic sortsupport interface for character type's operator classes.
* Includes locale support, and support for BpChar semantics (i.e. removing
* trailing spaces before comparison).
*
* Relies on the assumption that text, VarChar, BpChar, and bytea all have the
* same representation. Callers that always use the C collation (e.g.
* non-collatable type callers like bytea) may have NUL bytes in their strings;
* this will not work with any other collation, though.
*/
void
varstr_sortsupport(SortSupport ssup, Oid collid, bool bpchar)
{
bool abbreviate = ssup->abbreviate;
bool collate_c = false;
TextSortSupport *tss;
StringSortSupport *sss;
#ifdef HAVE_LOCALE_T
pg_locale_t locale = 0;
@ -1762,20 +1778,25 @@ btsortsupport_worker(SortSupport ssup, Oid collid)
* overhead of a trip through the fmgr layer for every comparison, which
* can be substantial.
*
* Most typically, we'll set the comparator to bttextfastcmp_locale, which
* uses strcoll() to perform comparisons. However, if LC_COLLATE = C, we
* can make things quite a bit faster with bttextfastcmp_c, which uses
* memcmp() rather than strcoll().
* Most typically, we'll set the comparator to varstrfastcmp_locale, which
* uses strcoll() to perform comparisons and knows about the special
* requirements of BpChar callers. However, if LC_COLLATE = C, we can make
* things quite a bit faster with varstrfastcmp_c or bpcharfastcmp_c,
* both of which use memcmp() rather than strcoll().
*
* There is a further exception on Windows. When the database encoding is
* UTF-8 and we are not using the C collation, complex hacks are required.
* We don't currently have a comparator that handles that case, so we fall
* back on the slow method of having the sort code invoke bttextcmp() via
* the fmgr trampoline.
* back on the slow method of having the sort code invoke bttextcmp() (in
* the case of text) via the fmgr trampoline.
*/
if (lc_collate_is_c(collid))
{
ssup->comparator = bttextfastcmp_c;
if (!bpchar)
ssup->comparator = varstrfastcmp_c;
else
ssup->comparator = bpcharfastcmp_c;
collate_c = true;
}
#ifdef WIN32
@ -1784,7 +1805,7 @@ btsortsupport_worker(SortSupport ssup, Oid collid)
#endif
else
{
ssup->comparator = bttextfastcmp_locale;
ssup->comparator = varstrfastcmp_locale;
/*
* We need a collation-sensitive comparison. To make things faster,
@ -1825,24 +1846,25 @@ btsortsupport_worker(SortSupport ssup, Oid collid)
/*
* If we're using abbreviated keys, or if we're using a locale-aware
* comparison, we need to initialize a TextSortSupport object. Both cases
* will make use of the temporary buffers we initialize here for scratch
* space, and the abbreviation case requires additional state.
* comparison, we need to initialize a StringSortSupport object. Both
* cases will make use of the temporary buffers we initialize here for
* scratch space (and to detect requirement for BpChar semantics from
* caller), and the abbreviation case requires additional state.
*/
if (abbreviate || !collate_c)
{
tss = palloc(sizeof(TextSortSupport));
tss->buf1 = palloc(TEXTBUFLEN);
tss->buflen1 = TEXTBUFLEN;
tss->buf2 = palloc(TEXTBUFLEN);
tss->buflen2 = TEXTBUFLEN;
sss = palloc(sizeof(StringSortSupport));
sss->buf1 = palloc(TEXTBUFLEN);
sss->buflen1 = TEXTBUFLEN;
sss->buf2 = palloc(TEXTBUFLEN);
sss->buflen2 = TEXTBUFLEN;
/* Start with invalid values */
tss->last_len1 = -1;
tss->last_len2 = -1;
sss->last_len1 = -1;
sss->last_len2 = -1;
/* Initialize */
tss->last_returned = 0;
sss->last_returned = 0;
#ifdef HAVE_LOCALE_T
tss->locale = locale;
sss->locale = locale;
#endif
/*
* To avoid somehow confusing a strxfrm() blob and an original string,
@ -1858,9 +1880,10 @@ btsortsupport_worker(SortSupport ssup, Oid collid)
*
* Arbitrarily initialize cache_blob to true.
*/
tss->cache_blob = true;
tss->collate_c = collate_c;
ssup->ssup_extra = tss;
sss->cache_blob = true;
sss->collate_c = collate_c;
sss->bpchar = bpchar;
ssup->ssup_extra = sss;
/*
* If possible, plan to use the abbreviated keys optimization. The
@ -1869,13 +1892,13 @@ btsortsupport_worker(SortSupport ssup, Oid collid)
*/
if (abbreviate)
{
tss->prop_card = 0.20;
initHyperLogLog(&tss->abbr_card, 10);
initHyperLogLog(&tss->full_card, 10);
sss->prop_card = 0.20;
initHyperLogLog(&sss->abbr_card, 10);
initHyperLogLog(&sss->full_card, 10);
ssup->abbrev_full_comparator = ssup->comparator;
ssup->comparator = bttextcmp_abbrev;
ssup->abbrev_converter = bttext_abbrev_convert;
ssup->abbrev_abort = bttext_abbrev_abort;
ssup->comparator = varstrcmp_abbrev;
ssup->abbrev_converter = varstr_abbrev_convert;
ssup->abbrev_abort = varstr_abbrev_abort;
}
}
}
@ -1884,10 +1907,10 @@ btsortsupport_worker(SortSupport ssup, Oid collid)
* sortsupport comparison func (for C locale case)
*/
static int
bttextfastcmp_c(Datum x, Datum y, SortSupport ssup)
varstrfastcmp_c(Datum x, Datum y, SortSupport ssup)
{
text *arg1 = DatumGetTextPP(x);
text *arg2 = DatumGetTextPP(y);
string *arg1 = DatumGetStringPP(x);
string *arg2 = DatumGetStringPP(y);
char *a1p,
*a2p;
int len1,
@ -1913,16 +1936,53 @@ bttextfastcmp_c(Datum x, Datum y, SortSupport ssup)
return result;
}
/*
* sortsupport comparison func (for BpChar C locale case)
*
* BpChar outsources its sortsupport to this module. Specialization for the
* varstr_sortsupport BpChar case, modeled on
* internal_bpchar_pattern_compare().
*/
static int
bpcharfastcmp_c(Datum x, Datum y, SortSupport ssup)
{
BpChar *arg1 = DatumGetBpCharPP(x);
BpChar *arg2 = DatumGetBpCharPP(y);
char *a1p,
*a2p;
int len1,
len2,
result;
a1p = VARDATA_ANY(arg1);
a2p = VARDATA_ANY(arg2);
len1 = bpchartruelen(a1p, VARSIZE_ANY_EXHDR(arg1));
len2 = bpchartruelen(a2p, VARSIZE_ANY_EXHDR(arg2));
result = memcmp(a1p, a2p, Min(len1, len2));
if ((result == 0) && (len1 != len2))
result = (len1 < len2) ? -1 : 1;
/* We can't afford to leak memory here. */
if (PointerGetDatum(arg1) != x)
pfree(arg1);
if (PointerGetDatum(arg2) != y)
pfree(arg2);
return result;
}
/*
* sortsupport comparison func (for locale case)
*/
static int
bttextfastcmp_locale(Datum x, Datum y, SortSupport ssup)
varstrfastcmp_locale(Datum x, Datum y, SortSupport ssup)
{
text *arg1 = DatumGetTextPP(x);
text *arg2 = DatumGetTextPP(y);
string *arg1 = DatumGetStringPP(x);
string *arg2 = DatumGetStringPP(y);
bool arg1_match;
TextSortSupport *tss = (TextSortSupport *) ssup->ssup_extra;
StringSortSupport *sss = (StringSortSupport *) ssup->ssup_extra;
/* working state */
char *a1p,
@ -1944,41 +2004,56 @@ bttextfastcmp_locale(Datum x, Datum y, SortSupport ssup)
* No change in buf1 or buf2 contents, so avoid changing last_len1 or
* last_len2. Existing contents of buffers might still be used by next
* call.
*
* It's fine to allow the comparison of BpChar padding bytes here, even
* though that implies that the memcmp() will usually be performed for
* BpChar callers (though multibyte characters could still prevent that
* from occurring). The memcmp() is still very cheap, and BpChar's
* funny semantics have us remove trailing spaces (not limited to
* padding), so we need make no distinction between padding space
* characters and "real" space characters.
*/
result = 0;
goto done;
}
if (len1 >= tss->buflen1)
if (sss->bpchar)
{
pfree(tss->buf1);
tss->buflen1 = Max(len1 + 1, Min(tss->buflen1 * 2, MaxAllocSize));
tss->buf1 = MemoryContextAlloc(ssup->ssup_cxt, tss->buflen1);
/* Get true number of bytes, ignoring trailing spaces */
len1 = bpchartruelen(a1p, len1);
len2 = bpchartruelen(a2p, len2);
}
if (len2 >= tss->buflen2)
if (len1 >= sss->buflen1)
{
pfree(tss->buf2);
tss->buflen2 = Max(len2 + 1, Min(tss->buflen2 * 2, MaxAllocSize));
tss->buf2 = MemoryContextAlloc(ssup->ssup_cxt, tss->buflen2);
pfree(sss->buf1);
sss->buflen1 = Max(len1 + 1, Min(sss->buflen1 * 2, MaxAllocSize));
sss->buf1 = MemoryContextAlloc(ssup->ssup_cxt, sss->buflen1);
}
if (len2 >= sss->buflen2)
{
pfree(sss->buf2);
sss->buflen2 = Max(len2 + 1, Min(sss->buflen2 * 2, MaxAllocSize));
sss->buf2 = MemoryContextAlloc(ssup->ssup_cxt, sss->buflen2);
}
/*
* We're likely to be asked to compare the same strings repeatedly, and
* memcmp() is so much cheaper than strcoll() that it pays to try to cache
* comparisons, even though in general there is no reason to think that
* that will work out (every text datum may be unique). Caching does not
* that will work out (every string datum may be unique). Caching does not
* slow things down measurably when it doesn't work out, and can speed
* things up by rather a lot when it does. In part, this is because the
* memcmp() compares data from cachelines that are needed in L1 cache even
* when the last comparison's result cannot be reused.
*/
arg1_match = true;
if (len1 != tss->last_len1 || memcmp(tss->buf1, a1p, len1) != 0)
if (len1 != sss->last_len1 || memcmp(sss->buf1, a1p, len1) != 0)
{
arg1_match = false;
memcpy(tss->buf1, a1p, len1);
tss->buf1[len1] = '\0';
tss->last_len1 = len1;
memcpy(sss->buf1, a1p, len1);
sss->buf1[len1] = '\0';
sss->last_len1 = len1;
}
/*
@ -1987,25 +2062,25 @@ bttextfastcmp_locale(Datum x, Datum y, SortSupport ssup)
* it seems (at least with moderate to low cardinality sets), because
* quicksort compares the same pivot against many values.
*/
if (len2 != tss->last_len2 || memcmp(tss->buf2, a2p, len2) != 0)
if (len2 != sss->last_len2 || memcmp(sss->buf2, a2p, len2) != 0)
{
memcpy(tss->buf2, a2p, len2);
tss->buf2[len2] = '\0';
tss->last_len2 = len2;
memcpy(sss->buf2, a2p, len2);
sss->buf2[len2] = '\0';
sss->last_len2 = len2;
}
else if (arg1_match && !tss->cache_blob)
else if (arg1_match && !sss->cache_blob)
{
/* Use result cached following last actual strcoll() call */
result = tss->last_returned;
result = sss->last_returned;
goto done;
}
#ifdef HAVE_LOCALE_T
if (tss->locale)
result = strcoll_l(tss->buf1, tss->buf2, tss->locale);
if (sss->locale)
result = strcoll_l(sss->buf1, sss->buf2, sss->locale);
else
#endif
result = strcoll(tss->buf1, tss->buf2);
result = strcoll(sss->buf1, sss->buf2);
/*
* In some locales strcoll() can claim that nonidentical strings are
@ -2013,11 +2088,11 @@ bttextfastcmp_locale(Datum x, Datum y, SortSupport ssup)
* follow Perl's lead and sort "equal" strings according to strcmp().
*/
if (result == 0)
result = strcmp(tss->buf1, tss->buf2);
result = strcmp(sss->buf1, sss->buf2);
/* Cache result, perhaps saving an expensive strcoll() call next time */
tss->cache_blob = false;
tss->last_returned = result;
sss->cache_blob = false;
sss->last_returned = result;
done:
/* We can't afford to leak memory here. */
if (PointerGetDatum(arg1) != x)
@ -2032,13 +2107,14 @@ done:
* Abbreviated key comparison func
*/
static int
bttextcmp_abbrev(Datum x, Datum y, SortSupport ssup)
varstrcmp_abbrev(Datum x, Datum y, SortSupport ssup)
{
/*
* When 0 is returned, the core system will call bttextfastcmp_c() or
* bttextfastcmp_locale(). Even a strcmp() on two non-truncated strxfrm()
* blobs cannot indicate *equality* authoritatively, for the same reason
* that there is a strcoll() tie-breaker call to strcmp() in varstr_cmp().
* When 0 is returned, the core system will call varstrfastcmp_c()
* (bpcharfastcmp_c() in BpChar case) or varstrfastcmp_locale(). Even a
* strcmp() on two non-truncated strxfrm() blobs cannot indicate *equality*
* authoritatively, for the same reason that there is a strcoll()
* tie-breaker call to strcmp() in varstr_cmp().
*/
if (x > y)
return 1;
@ -2049,16 +2125,17 @@ bttextcmp_abbrev(Datum x, Datum y, SortSupport ssup)
}
/*
* Conversion routine for sortsupport. Converts original text to abbreviated
* key representation. Our encoding strategy is simple -- pack the first 8
* bytes of a strxfrm() blob into a Datum (on little-endian machines, the 8
* bytes are stored in reverse order), and treat it as an unsigned integer.
* Conversion routine for sortsupport. Converts original to abbreviated key
* representation. Our encoding strategy is simple -- pack the first 8 bytes
* of a strxfrm() blob into a Datum (on little-endian machines, the 8 bytes are
* stored in reverse order), and treat it as an unsigned integer. When the "C"
* locale is used, or in case of bytea, just memcpy() from original instead.
*/
static Datum
bttext_abbrev_convert(Datum original, SortSupport ssup)
varstr_abbrev_convert(Datum original, SortSupport ssup)
{
TextSortSupport *tss = (TextSortSupport *) ssup->ssup_extra;
text *authoritative = DatumGetTextPP(original);
StringSortSupport *sss = (StringSortSupport *) ssup->ssup_extra;
string *authoritative = DatumGetStringPP(original);
char *authoritative_data = VARDATA_ANY(authoritative);
/* working state */
@ -2072,13 +2149,38 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
memset(pres, 0, sizeof(Datum));
len = VARSIZE_ANY_EXHDR(authoritative);
/* Get number of bytes, ignoring trailing spaces */
if (sss->bpchar)
len = bpchartruelen(authoritative_data, len);
/*
* If we're using the C collation, use memcmp(), rather than strxfrm(), to
* abbreviate keys. The full comparator for the C locale is always
* memcmp(), and we can't risk having this give a different answer.
* Besides, this should be faster, too.
* memcmp(). It would be incorrect to allow bytea callers (callers that
* always force the C collation -- bytea isn't a collatable type, but this
* approach is convenient) to use strxfrm(). This is because bytea strings
* may contain NUL bytes. Besides, this should be faster, too.
*
* More generally, it's okay that bytea callers can have NUL bytes in
* strings because varstrcmp_abbrev() need not make a distinction between
* terminating NUL bytes, and NUL bytes representing actual NULs in the
* authoritative representation. Hopefully a comparison at or past one
* abbreviated key's terminating NUL byte will resolve the comparison
* without consulting the authoritative representation; specifically, some
* later non-NUL byte in the longer string can resolve the comparison
* against a subsequent terminating NUL in the shorter string. There will
* usually be what is effectively a "length-wise" resolution there and
* then.
*
* If that doesn't work out -- if all bytes in the longer string positioned
* at or past the offset of the smaller string's (first) terminating NUL
* are actually representative of NUL bytes in the authoritative binary
* string (perhaps with some *terminating* NUL bytes towards the end of the
* longer string iff it happens to still be small) -- then an authoritative
* tie-breaker will happen, and do the right thing: explicitly consider
* string length.
*/
if (tss->collate_c)
if (sss->collate_c)
memcpy(pres, authoritative_data, Min(len, sizeof(Datum)));
else
{
@ -2088,50 +2190,50 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
* We're not using the C collation, so fall back on strxfrm.
*/
/* By convention, we use buffer 1 to store and NUL-terminate text */
if (len >= tss->buflen1)
/* By convention, we use buffer 1 to store and NUL-terminate */
if (len >= sss->buflen1)
{
pfree(tss->buf1);
tss->buflen1 = Max(len + 1, Min(tss->buflen1 * 2, MaxAllocSize));
tss->buf1 = palloc(tss->buflen1);
pfree(sss->buf1);
sss->buflen1 = Max(len + 1, Min(sss->buflen1 * 2, MaxAllocSize));
sss->buf1 = palloc(sss->buflen1);
}
/* Might be able to reuse strxfrm() blob from last call */
if (tss->last_len1 == len && tss->cache_blob &&
memcmp(tss->buf1, authoritative_data, len) == 0)
if (sss->last_len1 == len && sss->cache_blob &&
memcmp(sss->buf1, authoritative_data, len) == 0)
{
memcpy(pres, tss->buf2, Min(sizeof(Datum), tss->last_len2));
memcpy(pres, sss->buf2, Min(sizeof(Datum), sss->last_len2));
/* No change affecting cardinality, so no hashing required */
goto done;
}
/* Just like strcoll(), strxfrm() expects a NUL-terminated string */
memcpy(tss->buf1, authoritative_data, len);
tss->buf1[len] = '\0';
tss->last_len1 = len;
memcpy(sss->buf1, authoritative_data, len);
sss->buf1[len] = '\0';
sss->last_len1 = len;
for (;;)
{
#ifdef HAVE_LOCALE_T
if (tss->locale)
bsize = strxfrm_l(tss->buf2, tss->buf1,
tss->buflen2, tss->locale);
if (sss->locale)
bsize = strxfrm_l(sss->buf2, sss->buf1,
sss->buflen2, sss->locale);
else
#endif
bsize = strxfrm(tss->buf2, tss->buf1, tss->buflen2);
bsize = strxfrm(sss->buf2, sss->buf1, sss->buflen2);
tss->last_len2 = bsize;
if (bsize < tss->buflen2)
sss->last_len2 = bsize;
if (bsize < sss->buflen2)
break;
/*
* The C standard states that the contents of the buffer is now
* unspecified. Grow buffer, and retry.
*/
pfree(tss->buf2);
tss->buflen2 = Max(bsize + 1,
Min(tss->buflen2 * 2, MaxAllocSize));
tss->buf2 = palloc(tss->buflen2);
pfree(sss->buf2);
sss->buflen2 = Max(bsize + 1,
Min(sss->buflen2 * 2, MaxAllocSize));
sss->buf2 = palloc(sss->buflen2);
}
/*
@ -2139,8 +2241,11 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
* strxfrm() blob is itself NUL terminated, leaving no danger of
* misinterpreting any NUL bytes not intended to be interpreted as
* logically representing termination.
*
* (Actually, even if there were NUL bytes in the blob it would be
* okay. See remarks on bytea case above.)
*/
memcpy(pres, tss->buf2, Min(sizeof(Datum), bsize));
memcpy(pres, sss->buf2, Min(sizeof(Datum), bsize));
}
/*
@ -2148,7 +2253,7 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
* authoritative keys using HyperLogLog. Used as cheap insurance against
* the worst case, where we do many string transformations for no saving
* in full strcoll()-based comparisons. These statistics are used by
* bttext_abbrev_abort().
* varstr_abbrev_abort().
*
* First, Hash key proper, or a significant fraction of it. Mix in length
* in order to compensate for cases where differences are past
@ -2160,7 +2265,7 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
if (len > PG_CACHE_LINE_SIZE)
hash ^= DatumGetUInt32(hash_uint32((uint32) len));
addHyperLogLog(&tss->full_card, hash);
addHyperLogLog(&sss->full_card, hash);
/* Hash abbreviated key */
#if SIZEOF_DATUM == 8
@ -2176,15 +2281,15 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
hash = DatumGetUInt32(hash_uint32((uint32) res));
#endif
addHyperLogLog(&tss->abbr_card, hash);
addHyperLogLog(&sss->abbr_card, hash);
/* Cache result, perhaps saving an expensive strxfrm() call next time */
tss->cache_blob = true;
sss->cache_blob = true;
done:
/*
* Byteswap on little-endian machines.
*
* This is needed so that bttextcmp_abbrev() (an unsigned integer 3-way
* This is needed so that varstrcmp_abbrev() (an unsigned integer 3-way
* comparator) works correctly on all platforms. If we didn't do this,
* the comparator would have to call memcmp() with a pair of pointers to
* the first byte of each abbreviated key, which is slower.
@ -2204,9 +2309,9 @@ done:
* should be aborted, based on its projected effectiveness.
*/
static bool
bttext_abbrev_abort(int memtupcount, SortSupport ssup)
varstr_abbrev_abort(int memtupcount, SortSupport ssup)
{
TextSortSupport *tss = (TextSortSupport *) ssup->ssup_extra;
StringSortSupport *sss = (StringSortSupport *) ssup->ssup_extra;
double abbrev_distinct,
key_distinct;
@ -2216,8 +2321,8 @@ bttext_abbrev_abort(int memtupcount, SortSupport ssup)
if (memtupcount < 100)
return false;
abbrev_distinct = estimateHyperLogLog(&tss->abbr_card);
key_distinct = estimateHyperLogLog(&tss->full_card);
abbrev_distinct = estimateHyperLogLog(&sss->abbr_card);
key_distinct = estimateHyperLogLog(&sss->full_card);
/*
* Clamp cardinality estimates to at least one distinct value. While
@ -2240,10 +2345,10 @@ bttext_abbrev_abort(int memtupcount, SortSupport ssup)
{
double norm_abbrev_card = abbrev_distinct / (double) memtupcount;
elog(LOG, "bttext_abbrev: abbrev_distinct after %d: %f "
elog(LOG, "varstr_abbrev: abbrev_distinct after %d: %f "
"(key_distinct: %f, norm_abbrev_card: %f, prop_card: %f)",
memtupcount, abbrev_distinct, key_distinct, norm_abbrev_card,
tss->prop_card);
sss->prop_card);
}
#endif
@ -2263,7 +2368,7 @@ bttext_abbrev_abort(int memtupcount, SortSupport ssup)
* abbreviated comparison with a cheap memcmp()-based authoritative
* resolution are equivalent.
*/
if (abbrev_distinct > key_distinct * tss->prop_card)
if (abbrev_distinct > key_distinct * sss->prop_card)
{
/*
* When we have exceeded 10,000 tuples, decay required cardinality
@ -2291,7 +2396,7 @@ bttext_abbrev_abort(int memtupcount, SortSupport ssup)
* apparent it's probably not worth aborting.
*/
if (memtupcount > 10000)
tss->prop_card *= 0.65;
sss->prop_card *= 0.65;
return false;
}
@ -2309,9 +2414,9 @@ bttext_abbrev_abort(int memtupcount, SortSupport ssup)
*/
#ifdef TRACE_SORT
if (trace_sort)
elog(LOG, "bttext_abbrev: aborted abbreviation at %d "
elog(LOG, "varstr_abbrev: aborted abbreviation at %d "
"(abbrev_distinct: %f, key_distinct: %f, prop_card: %f)",
memtupcount, abbrev_distinct, key_distinct, tss->prop_card);
memtupcount, abbrev_distinct, key_distinct, sss->prop_card);
#endif
return true;
@ -2345,8 +2450,9 @@ text_smaller(PG_FUNCTION_ARGS)
/*
* The following operators support character-by-character comparison
* of text datums, to allow building indexes suitable for LIKE clauses.
* Note that the regular texteq/textne comparison operators are assumed
* to be compatible with these!
* Note that the regular texteq/textne comparison operators, and regular
* support functions 1 and 2 with "C" collation are assumed to be
* compatible with these!
*/
static int
@ -2451,6 +2557,23 @@ bttext_pattern_cmp(PG_FUNCTION_ARGS)
}
Datum
bttext_pattern_sortsupport(PG_FUNCTION_ARGS)
{
SortSupport ssup = (SortSupport) PG_GETARG_POINTER(0);
MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(ssup->ssup_cxt);
/* Use generic string SortSupport, forcing "C" collation */
varstr_sortsupport(ssup, C_COLLATION_OID, false);
MemoryContextSwitchTo(oldcontext);
PG_RETURN_VOID();
}
/*-------------------------------------------------------------
* byteaoctetlen
*
@ -3375,6 +3498,22 @@ byteacmp(PG_FUNCTION_ARGS)
PG_RETURN_INT32(cmp);
}
Datum
bytea_sortsupport(PG_FUNCTION_ARGS)
{
SortSupport ssup = (SortSupport) PG_GETARG_POINTER(0);
MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(ssup->ssup_cxt);
/* Use generic string SortSupport, forcing "C" collation */
varstr_sortsupport(ssup, C_COLLATION_OID, false);
MemoryContextSwitchTo(oldcontext);
PG_RETURN_VOID();
}
/*
* appendStringInfoText
*

2
src/include/catalog/catversion.h
View File

@ -53,6 +53,6 @@
*/
/* yyyymmddN */
#define CATALOG_VERSION_NO 201601281
#define CATALOG_VERSION_NO 201602031
#endif

4
src/include/catalog/pg_amproc.h
View File

@ -80,7 +80,9 @@ DATA(insert ( 421 702 702 1 357 ));
DATA(insert ( 423 1560 1560 1 1596 ));
DATA(insert ( 424 16 16 1 1693 ));
DATA(insert ( 426 1042 1042 1 1078 ));
DATA(insert ( 426 1042 1042 2 3328 ));
DATA(insert ( 428 17 17 1 1954 ));
DATA(insert ( 428 17 17 2 3331 ));
DATA(insert ( 429 18 18 1 358 ));
DATA(insert ( 434 1082 1082 1 1092 ));
DATA(insert ( 434 1082 1082 2 3136 ));
@ -128,7 +130,9 @@ DATA(insert ( 1996 1083 1083 1 1107 ));
DATA(insert ( 2000 1266 1266 1 1358 ));
DATA(insert ( 2002 1562 1562 1 1672 ));
DATA(insert ( 2095 25 25 1 2166 ));
DATA(insert ( 2095 25 25 2 3332 ));
DATA(insert ( 2097 1042 1042 1 2180 ));
DATA(insert ( 2097 1042 1042 2 3333 ));
DATA(insert ( 2099 790 790 1 377 ));
DATA(insert ( 2233 703 703 1 380 ));
DATA(insert ( 2234 704 704 1 381 ));

8
src/include/catalog/pg_proc.h
View File

@ -1130,6 +1130,8 @@ DATA(insert OID = 1064 ( bpchar_smaller PGNSP PGUID 12 1 0 0 0 f f f f t f i
DESCR("smaller of two");
DATA(insert OID = 1078 ( bpcharcmp PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 23 "1042 1042" _null_ _null_ _null_ _null_ _null_ bpcharcmp _null_ _null_ _null_ ));
DESCR("less-equal-greater");
DATA(insert OID = 3328 ( bpchar_sortsupport PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 2278 "2281" _null_ _null_ _null_ _null_ _null_ bpchar_sortsupport _null_ _null_ _null_ ));
DESCR("sort support");
DATA(insert OID = 1080 ( hashbpchar PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 23 "1042" _null_ _null_ _null_ _null_ _null_ hashbpchar _null_ _null_ _null_ ));
DESCR("hash");
DATA(insert OID = 1081 ( format_type PGNSP PGUID 12 1 0 0 0 f f f f f f s s 2 0 25 "26 23" _null_ _null_ _null_ _null_ _null_ format_type _null_ _null_ _null_ ));
@ -2861,6 +2863,8 @@ DATA(insert OID = 1952 ( byteage PGNSP PGUID 12 1 0 0 0 f f f t t f i s 2 0
DATA(insert OID = 1953 ( byteane PGNSP PGUID 12 1 0 0 0 f f f t t f i s 2 0 16 "17 17" _null_ _null_ _null_ _null_ _null_ byteane _null_ _null_ _null_ ));
DATA(insert OID = 1954 ( byteacmp PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 23 "17 17" _null_ _null_ _null_ _null_ _null_ byteacmp _null_ _null_ _null_ ));
DESCR("less-equal-greater");
DATA(insert OID = 3331 ( bytea_sortsupport PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 2278 "2281" _null_ _null_ _null_ _null_ _null_ bytea_sortsupport _null_ _null_ _null_ ));
DESCR("sort support");
DATA(insert OID = 3917 ( timestamp_transform PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 2281 "2281" _null_ _null_ _null_ _null_ _null_ timestamp_transform _null_ _null_ _null_ ));
DESCR("transform a timestamp length coercion");
@ -3373,6 +3377,8 @@ DATA(insert OID = 2163 ( text_pattern_ge PGNSP PGUID 12 1 0 0 0 f f f f t f i s
DATA(insert OID = 2164 ( text_pattern_gt PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "25 25" _null_ _null_ _null_ _null_ _null_ text_pattern_gt _null_ _null_ _null_ ));
DATA(insert OID = 2166 ( bttext_pattern_cmp PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 23 "25 25" _null_ _null_ _null_ _null_ _null_ bttext_pattern_cmp _null_ _null_ _null_ ));
DESCR("less-equal-greater");
DATA(insert OID = 3332 ( bttext_pattern_sortsupport PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 2278 "2281" _null_ _null_ _null_ _null_ _null_ bttext_pattern_sortsupport _null_ _null_ _null_ ));
DESCR("sort support");
DATA(insert OID = 2174 ( bpchar_pattern_lt PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "1042 1042" _null_ _null_ _null_ _null_ _null_ bpchar_pattern_lt _null_ _null_ _null_ ));
DATA(insert OID = 2175 ( bpchar_pattern_le PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "1042 1042" _null_ _null_ _null_ _null_ _null_ bpchar_pattern_le _null_ _null_ _null_ ));
@ -3380,6 +3386,8 @@ DATA(insert OID = 2177 ( bpchar_pattern_ge PGNSP PGUID 12 1 0 0 0 f f f f t f
DATA(insert OID = 2178 ( bpchar_pattern_gt PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "1042 1042" _null_ _null_ _null_ _null_ _null_ bpchar_pattern_gt _null_ _null_ _null_ ));
DATA(insert OID = 2180 ( btbpchar_pattern_cmp PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 23 "1042 1042" _null_ _null_ _null_ _null_ _null_ btbpchar_pattern_cmp _null_ _null_ _null_ ));
DESCR("less-equal-greater");
DATA(insert OID = 3333 ( btbpchar_pattern_sortsupport PGNSP PGUID 12 1 0 0 0 f f f f t f i s 1 0 2278 "2281" _null_ _null_ _null_ _null_ _null_ btbpchar_pattern_sortsupport _null_ _null_ _null_ ));
DESCR("sort support");
DATA(insert OID = 2188 ( btint48cmp PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 23 "23 20" _null_ _null_ _null_ _null_ _null_ btint48cmp _null_ _null_ _null_ ));
DESCR("less-equal-greater");

6
src/include/utils/builtins.h
View File

@ -16,6 +16,7 @@
#include "fmgr.h"
#include "nodes/parsenodes.h"
#include "utils/sortsupport.h"
/*
* Defined in adt/
@ -761,8 +762,10 @@ extern Datum bpcharle(PG_FUNCTION_ARGS);
extern Datum bpchargt(PG_FUNCTION_ARGS);
extern Datum bpcharge(PG_FUNCTION_ARGS);
extern Datum bpcharcmp(PG_FUNCTION_ARGS);
extern Datum bpchar_sortsupport(PG_FUNCTION_ARGS);
extern Datum bpchar_larger(PG_FUNCTION_ARGS);
extern Datum bpchar_smaller(PG_FUNCTION_ARGS);
extern int bpchartruelen(char *s, int len);
extern Datum bpcharlen(PG_FUNCTION_ARGS);
extern Datum bpcharoctetlen(PG_FUNCTION_ARGS);
extern Datum hashbpchar(PG_FUNCTION_ARGS);
@ -771,6 +774,7 @@ extern Datum bpchar_pattern_le(PG_FUNCTION_ARGS);
extern Datum bpchar_pattern_gt(PG_FUNCTION_ARGS);
extern Datum bpchar_pattern_ge(PG_FUNCTION_ARGS);
extern Datum btbpchar_pattern_cmp(PG_FUNCTION_ARGS);
extern Datum btbpchar_pattern_sortsupport(PG_FUNCTION_ARGS);
extern Datum varcharin(PG_FUNCTION_ARGS);
extern Datum varcharout(PG_FUNCTION_ARGS);
@ -808,6 +812,7 @@ extern Datum text_pattern_le(PG_FUNCTION_ARGS);
extern Datum text_pattern_gt(PG_FUNCTION_ARGS);
extern Datum text_pattern_ge(PG_FUNCTION_ARGS);
extern Datum bttext_pattern_cmp(PG_FUNCTION_ARGS);
extern Datum bttext_pattern_sortsupport(PG_FUNCTION_ARGS);
extern Datum textlen(PG_FUNCTION_ARGS);
extern Datum textoctetlen(PG_FUNCTION_ARGS);
extern Datum textpos(PG_FUNCTION_ARGS);
@ -818,6 +823,7 @@ extern Datum textoverlay_no_len(PG_FUNCTION_ARGS);
extern Datum name_text(PG_FUNCTION_ARGS);
extern Datum text_name(PG_FUNCTION_ARGS);
extern int varstr_cmp(char *arg1, int len1, char *arg2, int len2, Oid collid);
extern void varstr_sortsupport(SortSupport ssup, Oid collid, bool bpchar);
extern int varstr_levenshtein(const char *source, int slen,
const char *target, int tlen,
int ins_c, int del_c, int sub_c,

1
src/include/utils/bytea.h
View File

@ -42,6 +42,7 @@ extern Datum byteale(PG_FUNCTION_ARGS);
extern Datum byteagt(PG_FUNCTION_ARGS);
extern Datum byteage(PG_FUNCTION_ARGS);
extern Datum byteacmp(PG_FUNCTION_ARGS);
extern Datum bytea_sortsupport(PG_FUNCTION_ARGS);
extern Datum byteacat(PG_FUNCTION_ARGS);
extern Datum byteapos(PG_FUNCTION_ARGS);
extern Datum bytea_substr(PG_FUNCTION_ARGS);