Fixed Windows build [skip ci]

As the data is aligned, for hnsw, the combined size won't be in the range
(8156 (maxSize exlucding `ItemIdData`), 8160]. So even if the
ItemIdData is not included in the maxSize, it works well now, but I
think it's better to make it correct.

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## 0.5.1 (unreleased)
 
+- Added check for MVCC-compliant snapshot for HNSW index scans
 - Improved performance of index scans for IVFFlat after updates and deletes
 
 ## 0.5.0 (2023-08-28)

Makefile

@@ -3,8 +3,8 @@ EXTVERSION = 0.5.0
 
 MODULE_big = vector
 DATA = $(wildcard sql/*--*.sql)
-OBJS = src/hnsw.o src/hnswbuild.o src/hnswinsert.o src/hnswscan.o src/hnswutils.o src/hnswvacuum.o src/ivfbuild.o src/ivfflat.o src/ivfinsert.o src/ivfkmeans.o src/ivfscan.o src/ivfutils.o src/ivfvacuum.o src/vector.o
+OBJS = src/hnsw.o src/hnswbuild.o src/hnswinsert.o src/hnswscan.o src/hnswutils.o src/hnswvacuum.o src/ivfbuild.o src/ivfflat.o src/ivfinsert.o src/ivfkmeans.o src/ivfscan.o src/ivfutils.o src/ivfvacuum.o src/tinyint.o src/vector.o
-HEADERS = src/vector.h
+HEADERS = src/tinyint.h src/vector.h
 
 TESTS = $(wildcard test/sql/*.sql)
 REGRESS = $(patsubst test/sql/%.sql,%,$(TESTS))

Makefile.win

@@ -1,8 +1,8 @@
 EXTENSION = vector
 EXTVERSION = 0.5.0
 
-OBJS = src\hnsw.obj src\hnswbuild.obj src\hnswinsert.obj src\hnswscan.obj src\hnswutils.obj src\hnswvacuum.obj src\ivfbuild.obj src\ivfflat.obj src\ivfinsert.obj src\ivfkmeans.obj src\ivfscan.obj src\ivfutils.obj src\ivfvacuum.obj src\vector.obj
+OBJS = src\hnsw.obj src\hnswbuild.obj src\hnswinsert.obj src\hnswscan.obj src\hnswutils.obj src\hnswvacuum.obj src\ivfbuild.obj src\ivfflat.obj src\ivfinsert.obj src\ivfkmeans.obj src\ivfscan.obj src\ivfutils.obj src\ivfvacuum.obj src\tinyint.obj src\vector.obj
-HEADERS = src\vector.h
+HEADERS = src\tinyint.h src\vector.h
 
 REGRESS = btree cast copy functions input ivfflat_cosine ivfflat_ip ivfflat_l2 ivfflat_options ivfflat_unlogged
 REGRESS_OPTS = --inputdir=test --load-extension=$(EXTENSION)
@@ -56,7 +56,7 @@ install:
 	copy $(EXTENSION).control "$(SHAREDIR)\extension"
 	copy sql\$(EXTENSION)--*.sql "$(SHAREDIR)\extension"
 	mkdir "$(INCLUDEDIR_SERVER)\extension\$(EXTENSION)"
-	copy $(HEADERS) "$(INCLUDEDIR_SERVER)\extension\$(EXTENSION)"
+	for %f in ($(HEADERS)) do copy %f "$(INCLUDEDIR_SERVER)\extension\$(EXTENSION)"
 
 installcheck:
 	"$(BINDIR)\pg_regress" --bindir="$(BINDIR)" $(REGRESS_OPTS) $(REGRESS)

sql/vector--0.5.0--0.5.1.sql

@@ -0,0 +1,67 @@
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "ALTER EXTENSION vector UPDATE TO '0.5.1'" to load this file. \quit
+
+-- tinyint
+
+CREATE TYPE tinyint;
+
+CREATE FUNCTION tinyint_in(cstring, oid, integer) RETURNS tinyint
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION tinyint_out(tinyint) RETURNS cstring
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION tinyint_recv(internal, oid, integer) RETURNS tinyint
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION tinyint_send(tinyint) RETURNS bytea
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE TYPE tinyint (
+	INPUT     = tinyint_in,
+	OUTPUT    = tinyint_out,
+	RECEIVE   = tinyint_recv,
+	SEND      = tinyint_send,
+	INTERNALLENGTH = 1,
+	PASSEDBYVALUE,
+	ALIGNMENT = char
+);
+
+CREATE FUNCTION integer_to_tinyint(integer, integer, boolean) RETURNS tinyint
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION numeric_to_tinyint(numeric, integer, boolean) RETURNS tinyint
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE CAST (integer AS tinyint)
+	WITH FUNCTION integer_to_tinyint(integer, integer, boolean) AS IMPLICIT;
+
+CREATE CAST (numeric AS tinyint)
+	WITH FUNCTION numeric_to_tinyint(numeric, integer, boolean) AS IMPLICIT;
+
+CREATE FUNCTION l2_distance(tinyint[], tinyint[]) RETURNS float8
+	AS 'MODULE_PATHNAME', 'tinyint_l2_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION inner_product(tinyint[], tinyint[]) RETURNS float8
+	AS 'MODULE_PATHNAME', 'tinyint_inner_product' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION cosine_distance(tinyint[], tinyint[]) RETURNS float8
+	AS 'MODULE_PATHNAME', 'tinyint_cosine_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION tinyint_negative_inner_product(tinyint[], tinyint[]) RETURNS float8
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE OPERATOR <-> (
+	LEFTARG = tinyint[], RIGHTARG = tinyint[], PROCEDURE = l2_distance,
+	COMMUTATOR = '<->'
+);
+
+CREATE OPERATOR <#> (
+	LEFTARG = tinyint[], RIGHTARG = tinyint[], PROCEDURE = tinyint_negative_inner_product,
+	COMMUTATOR = '<#>'
+);
+
+CREATE OPERATOR <=> (
+	LEFTARG = tinyint[], RIGHTARG = tinyint[], PROCEDURE = cosine_distance,
+	COMMUTATOR = '<=>'
+);

sql/vector.sql

@@ -290,3 +290,68 @@ CREATE OPERATOR CLASS vector_cosine_ops
 	OPERATOR 1 <=> (vector, vector) FOR ORDER BY float_ops,
 	FUNCTION 1 vector_negative_inner_product(vector, vector),
 	FUNCTION 2 vector_norm(vector);
+
+-- tinyint
+
+CREATE TYPE tinyint;
+
+CREATE FUNCTION tinyint_in(cstring, oid, integer) RETURNS tinyint
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION tinyint_out(tinyint) RETURNS cstring
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION tinyint_recv(internal, oid, integer) RETURNS tinyint
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION tinyint_send(tinyint) RETURNS bytea
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE TYPE tinyint (
+	INPUT     = tinyint_in,
+	OUTPUT    = tinyint_out,
+	RECEIVE   = tinyint_recv,
+	SEND      = tinyint_send,
+	INTERNALLENGTH = 1,
+	PASSEDBYVALUE,
+	ALIGNMENT = char
+);
+
+CREATE FUNCTION integer_to_tinyint(integer, integer, boolean) RETURNS tinyint
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION numeric_to_tinyint(numeric, integer, boolean) RETURNS tinyint
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE CAST (integer AS tinyint)
+	WITH FUNCTION integer_to_tinyint(integer, integer, boolean) AS IMPLICIT;
+
+CREATE CAST (numeric AS tinyint)
+	WITH FUNCTION numeric_to_tinyint(numeric, integer, boolean) AS IMPLICIT;
+
+CREATE FUNCTION l2_distance(tinyint[], tinyint[]) RETURNS float8
+	AS 'MODULE_PATHNAME', 'tinyint_l2_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION inner_product(tinyint[], tinyint[]) RETURNS float8
+	AS 'MODULE_PATHNAME', 'tinyint_inner_product' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION cosine_distance(tinyint[], tinyint[]) RETURNS float8
+	AS 'MODULE_PATHNAME', 'tinyint_cosine_distance' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE FUNCTION tinyint_negative_inner_product(tinyint[], tinyint[]) RETURNS float8
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+CREATE OPERATOR <-> (
+	LEFTARG = tinyint[], RIGHTARG = tinyint[], PROCEDURE = l2_distance,
+	COMMUTATOR = '<->'
+);
+
+CREATE OPERATOR <#> (
+	LEFTARG = tinyint[], RIGHTARG = tinyint[], PROCEDURE = tinyint_negative_inner_product,
+	COMMUTATOR = '<#>'
+);
+
+CREATE OPERATOR <=> (
+	LEFTARG = tinyint[], RIGHTARG = tinyint[], PROCEDURE = cosine_distance,
+	COMMUTATOR = '<=>'
+);

src/hnsw.h

@@ -57,6 +57,8 @@
 /* PROGRESS_CREATEIDX_SUBPHASE_INITIALIZE is 1 */
 #define PROGRESS_HNSW_PHASE_LOAD		2
 
+#define HNSW_MAX_SIZE (BLCKSZ - MAXALIGN(SizeOfPageHeaderData) - MAXALIGN(sizeof(HnswPageOpaqueData)) - sizeof(ItemIdData))
+
 #define HNSW_ELEMENT_TUPLE_SIZE(_dim)	MAXALIGN(offsetof(HnswElementTupleData, vec) + VECTOR_SIZE(_dim))
 #define HNSW_NEIGHBOR_TUPLE_SIZE(level, m)	MAXALIGN(offsetof(HnswNeighborTupleData, indextids) + ((level) + 2) * (m) * sizeof(ItemPointerData))
 
@@ -110,13 +112,11 @@ typedef struct HnswCandidate
 {
 	HnswElement element;
 	float		distance;
-	bool		closer;
 }			HnswCandidate;
 
 typedef struct HnswNeighborArray
 {
 	int			length;
-	bool		closerSet;
 	HnswCandidate *items;
 }			HnswNeighborArray;
 

src/hnswbuild.c

@@ -117,12 +117,12 @@ CreateElementPages(HnswBuildState * buildstate)
 	ListCell   *lc;
 
 	/* Calculate sizes */
-	maxSize = BLCKSZ - MAXALIGN(SizeOfPageHeaderData) - MAXALIGN(sizeof(HnswPageOpaqueData));
+	maxSize = HNSW_MAX_SIZE;
 	etupSize = HNSW_ELEMENT_TUPLE_SIZE(dimensions);
 
 	/* Allocate once */
 	etup = palloc0(etupSize);
-	ntup = palloc0(maxSize);
+	ntup = palloc0(BLCKSZ);
 
 	/* Prepare first page */
 	buf = HnswNewBuffer(index, forkNum);

src/hnswinsert.c

@@ -135,7 +135,7 @@ WriteNewElementPages(Relation index, HnswElement e, int m, BlockNumber insertPag
 	etupSize = HNSW_ELEMENT_TUPLE_SIZE(dimensions);
 	ntupSize = HNSW_NEIGHBOR_TUPLE_SIZE(e->level, m);
 	combinedSize = etupSize + ntupSize + sizeof(ItemIdData);
-	maxSize = BLCKSZ - MAXALIGN(SizeOfPageHeaderData) - MAXALIGN(sizeof(HnswPageOpaqueData));
+	maxSize = HNSW_MAX_SIZE;
 	minCombinedSize = etupSize + HNSW_NEIGHBOR_TUPLE_SIZE(0, m) + sizeof(ItemIdData);
 
 	/* Prepare element tuple */

src/hnswscan.c

@@ -160,6 +160,11 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)
 		if (scan->orderByData == NULL)
 			elog(ERROR, "cannot scan hnsw index without order");
 
+		/* Requires MVCC-compliant snapshot as not able to maintain a pin */
+		/* https://www.postgresql.org/docs/current/index-locking.html */
+		if (!IsMVCCSnapshot(scan->xs_snapshot))
+			elog(ERROR, "non-MVCC snapshots are not supported with hnsw");
+
 		/* Get scan value */
 		value = GetScanValue(scan);
 
@@ -201,15 +206,6 @@ hnswgettuple(IndexScanDesc scan, ScanDirection dir)
 		scan->xs_ctup.t_self = *heaptid;
 #endif
 
-		/*
-		 * Typically, an index scan must maintain a pin on the index page
-		 * holding the item last returned by amgettuple. However, this is not
-		 * needed with the current vacuum strategy, which ensures scans do not
-		 * visit tuples in danger of being marked as deleted.
-		 *
-		 * https://www.postgresql.org/docs/current/index-locking.html
-		 */
-
 		scan->xs_recheckorderby = false;
 		return true;
 	}

src/hnswutils.c

@@ -139,7 +139,6 @@ HnswInitNeighbors(HnswElement element, int m)
 		a = &element->neighbors[lc];
 		a->length = 0;
 		a->items = palloc(sizeof(HnswCandidate) * lm);
-		a->closerSet = false;
 	}
 }
 
@@ -749,13 +748,11 @@ CheckElementCloser(HnswCandidate * e, List *r, int lc, FmgrInfo *procinfo, Oid c
  * Algorithm 4 from paper
  */
 static List *
-SelectNeighbors(List *c, int m, int lc, FmgrInfo *procinfo, Oid collation, HnswElement e2, HnswCandidate * newCandidate, HnswCandidate * *pruned)
+SelectNeighbors(List *c, int m, int lc, FmgrInfo *procinfo, Oid collation, HnswCandidate * *pruned)
 {
 	List	   *r = NIL;
 	List	   *w = list_copy(c);
 	pairingheap *wd;
-	bool		mustCalculate = !e2->neighbors[lc].closerSet;
-	bool		foundNew = false;
 
 	if (list_length(w) <= m)
 		return w;
@@ -766,40 +763,18 @@ SelectNeighbors(List *c, int m, int lc, FmgrInfo *procinfo, Oid collation, HnswE
 	{
 		/* Assumes w is already ordered desc */
 		HnswCandidate *e = llast(w);
+		bool		closer;
 
 		w = list_delete_last(w);
 
-		/* Use previous state of r and wd to skip work when possible */
+		closer = CheckElementCloser(e, r, lc, procinfo, collation);
-		if (mustCalculate)
-			e->closer = CheckElementCloser(e, r, lc, procinfo, collation);
-		else if (foundNew)
-		{
-			/* If new or current candidate is not closer, no change in state */
-			if (newCandidate->closer && e->closer)
-			{
-				/* Only need to compare with new candidate */
-				float		distance = HnswGetDistance(e->element, newCandidate->element, lc, procinfo, collation);
 
-				e->closer = e->distance < distance;
+		if (closer)
-
-				if (!e->closer)
-					mustCalculate = true;
-			}
-		}
-		else if (e == newCandidate)
-		{
-			e->closer = CheckElementCloser(e, r, lc, procinfo, collation);
-			foundNew = true;
-		}
-
-		if (e->closer)
 			r = lappend(r, e);
 		else
 			pairingheap_add(wd, &(CreatePairingHeapNode(e)->ph_node));
 	}
 
-	e2->neighbors[lc].closerSet = true;
-
 	/* Keep pruned connections */
 	while (!pairingheap_is_empty(wd) && list_length(r) < m)
 		r = lappend(r, ((HnswPairingHeapNode *) pairingheap_remove_first(wd))->inner);
@@ -934,7 +909,7 @@ HnswUpdateConnection(HnswElement element, HnswCandidate * hc, int m, int lc, int
 			c = lappend(c, &hc2);
 			list_sort(c, CompareCandidateDistances);
 
-			SelectNeighbors(c, m, lc, procinfo, collation, hc->element, &hc2, &pruned);
+			SelectNeighbors(c, m, lc, procinfo, collation, &pruned);
 
 			/* Should not happen */
 			if (pruned == NULL)
@@ -1033,7 +1008,7 @@ HnswInsertElement(HnswElement element, HnswElement entryPoint, Relation index, F
 		else
 			lw = w;
 
-		neighbors = SelectNeighbors(lw, lm, lc, procinfo, collation, element, NULL, NULL);
+		neighbors = SelectNeighbors(lw, lm, lc, procinfo, collation, NULL);
 
 		AddConnections(element, neighbors, lm, lc);
 

src/ivfinsert.c

@@ -99,7 +99,7 @@ InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heap_tid, R
 
 	/* Get tuple size */
 	itemsz = MAXALIGN(IndexTupleSize(itup));
-	Assert(itemsz <= BLCKSZ - MAXALIGN(SizeOfPageHeaderData) - MAXALIGN(sizeof(IvfflatPageOpaqueData)));
+	Assert(itemsz <= BLCKSZ - MAXALIGN(SizeOfPageHeaderData) - MAXALIGN(sizeof(IvfflatPageOpaqueData)) - sizeof(ItemIdData));
 
 	/* Find a page to insert the item */
 	for (;;)

src/tinyint.c

@@ -0,0 +1,294 @@
+#include "postgres.h"
+
+#include <math.h>
+#include <stdint.h>
+
+#include "fmgr.h"
+#include "lib/stringinfo.h"
+#include "libpq/pqformat.h"
+#include "tinyint.h"
+#include "utils/array.h"
+#include "utils/builtins.h"
+#include "utils/numeric.h"
+
+/*
+ * Check if array is a vector
+ */
+static bool
+ArrayIsVector(ArrayType *a)
+{
+	return ARR_NDIM(a) == 1 && !array_contains_nulls(a);
+}
+
+/*
+ * Check if dimensions are the same
+ */
+static int
+CheckDims(ArrayType *a, ArrayType *b)
+{
+	int			dima;
+	int			dimb;
+
+	if (!ArrayIsVector(a) || !ArrayIsVector(b))
+		return 0;
+
+	dima = ARR_DIMS(a)[0];
+	dimb = ARR_DIMS(b)[0];
+
+	if (dima != dimb)
+		return 0;
+
+	return dima;
+}
+
+/*
+ * Check range
+ */
+static void
+CheckRange(long i)
+{
+	if (i < INT8_MIN || i > INT8_MAX)
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("value \"%ld\" is out of range for type tinyint", i)));
+}
+
+/*
+ * Convert textual representation to internal representation
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(tinyint_in);
+Datum
+tinyint_in(PG_FUNCTION_ARGS)
+{
+	char	   *s = PG_GETARG_CSTRING(0);
+	const char *ptr = s;
+	long		i;
+	char	   *end;
+
+	/* skip leading spaces */
+	while (*ptr != '\0' && isspace((unsigned char) *ptr))
+		ptr++;
+
+	if (*ptr == '\0')
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+				 errmsg("invalid input syntax for type tinyint: \"%s\"", s)));
+
+	i = strtol(ptr, &end, 10);
+	ptr = end;
+
+	if (i < INT8_MIN || i > INT8_MAX)
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("value \"%s\" is out of range for type tinyint", s)));
+
+	/* allow trailing whitespace, but not other trailing chars */
+	while (*ptr != '\0' && isspace((unsigned char) *ptr))
+		ptr++;
+
+	if (*ptr != '\0')
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+				 errmsg("invalid input syntax for type tinyint: \"%s\"", s)));
+
+	PG_RETURN_INT8(i);
+}
+
+/*
+ * Convert internal representation to textual representation
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(tinyint_out);
+Datum
+tinyint_out(PG_FUNCTION_ARGS)
+{
+	int8		num = PG_GETARG_INT8(0);
+	char	   *result = (char *) palloc(5);	/* sign, 3 digits, '\0' */
+
+	pg_ltoa((int32) num, result);
+	PG_RETURN_CSTRING(result);
+}
+
+/*
+ * Convert external binary representation to internal representation
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(tinyint_recv);
+Datum
+tinyint_recv(PG_FUNCTION_ARGS)
+{
+	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);
+
+	PG_RETURN_INT8((int8) pq_getmsgint(buf, sizeof(int8)));
+}
+
+/*
+ * Convert internal representation to the external binary representation
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(tinyint_send);
+Datum
+tinyint_send(PG_FUNCTION_ARGS)
+{
+	int8		arg1 = PG_GETARG_INT8(0);
+	StringInfoData buf;
+
+	pq_begintypsend(&buf);
+	pq_sendint8(&buf, arg1);
+	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
+}
+
+/*
+ * Convert integer to tinyint
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(integer_to_tinyint);
+Datum
+integer_to_tinyint(PG_FUNCTION_ARGS)
+{
+	int32		i = PG_GETARG_INT32(0);
+
+	CheckRange(i);
+
+	PG_RETURN_INT8(i);
+}
+
+/*
+ * Convert numeric to tinyint
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(numeric_to_tinyint);
+Datum
+numeric_to_tinyint(PG_FUNCTION_ARGS)
+{
+	Numeric		num = PG_GETARG_NUMERIC(0);
+	int32		i = numeric_int4_opt_error(num, NULL);
+
+	CheckRange(i);
+
+	PG_RETURN_INT8(i);
+}
+
+/*
+ * Get the L2 distance between tinyint arrays
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(tinyint_l2_distance);
+Datum
+tinyint_l2_distance(PG_FUNCTION_ARGS)
+{
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P(1);
+	int8    *ax = (int8 *) ARR_DATA_PTR(a);
+	int8    *bx = (int8 *) ARR_DATA_PTR(b);
+	double		distance = 0.0;
+	int			dim = CheckDims(a, b);
+
+	/* TODO Decide on error or NULL */
+	if (!dim)
+		PG_RETURN_NULL();
+
+	/* Auto-vectorized */
+	for (int i = 0; i < dim; i++)
+	{
+		double		diff = ax[i] - bx[i];
+
+		distance += diff * diff;
+	}
+
+	PG_RETURN_FLOAT8(sqrt(distance));
+}
+
+/*
+ * Get the inner product of two tinyint arrays
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(tinyint_inner_product);
+Datum
+tinyint_inner_product(PG_FUNCTION_ARGS)
+{
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P(1);
+	int8	   *ax = (int8 *) ARR_DATA_PTR(a);
+	int8	   *bx = (int8 *) ARR_DATA_PTR(b);
+	double		distance = 0.0;
+	int			dim = CheckDims(a, b);
+
+	/* TODO Decide on error or NULL */
+	if (!dim)
+		PG_RETURN_NULL();
+
+	/* Auto-vectorized */
+	for (int i = 0; i < dim; i++)
+		distance += ax[i] * bx[i];
+
+	PG_RETURN_FLOAT8(distance);
+}
+
+/*
+ * Get the negative inner product of two tinyint arrays
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(tinyint_negative_inner_product);
+Datum
+tinyint_negative_inner_product(PG_FUNCTION_ARGS)
+{
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P(1);
+	int8	   *ax = (int8 *) ARR_DATA_PTR(a);
+	int8	   *bx = (int8 *) ARR_DATA_PTR(b);
+	double		distance = 0.0;
+	int			dim = CheckDims(a, b);
+
+	/* TODO Decide on error or NULL */
+	if (!dim)
+		PG_RETURN_NULL();
+
+	/* Auto-vectorized */
+	for (int i = 0; i < dim; i++)
+		distance += ax[i] * bx[i];
+
+	PG_RETURN_FLOAT8(distance * -1);
+}
+
+/*
+ * Get the cosine distance between two float2 arrays
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(tinyint_cosine_distance);
+Datum
+tinyint_cosine_distance(PG_FUNCTION_ARGS)
+{
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P(1);
+	int8   *ax = (int8 *) ARR_DATA_PTR(a);
+	int8   *bx = (int8 *) ARR_DATA_PTR(b);
+	double		distance = 0.0;
+	double		norma = 0.0;
+	double		normb = 0.0;
+	double		similarity;
+	int			dim = CheckDims(a, b);
+
+	/* TODO Decide on error or NULL */
+	if (!dim)
+		PG_RETURN_NULL();
+
+	/* Auto-vectorized */
+	for (int i = 0; i < dim; i++)
+	{
+		float		axi = ax[i];
+		float		bxi = bx[i];
+
+		distance += axi * bxi;
+		norma += axi * axi;
+		normb += bxi * bxi;
+	}
+
+	/* Use sqrt(a * b) over sqrt(a) * sqrt(b) */
+	similarity = distance / sqrt(norma * normb);
+
+#ifdef _MSC_VER
+	/* /fp:fast may not propagate NaN */
+	if (isnan(similarity))
+		PG_RETURN_FLOAT8(NAN);
+#endif
+
+	/* Keep in range */
+	if (similarity > 1)
+		similarity = 1;
+	else if (similarity < -1)
+		similarity = -1;
+
+	PG_RETURN_FLOAT8(1 - similarity);
+}

src/tinyint.h

@@ -0,0 +1,8 @@
+#ifndef TINYINT_H
+#define TINYINT_H
+
+#define DatumGetInt8(X) ((int8) (X))
+#define PG_GETARG_INT8(n)	 DatumGetInt8(PG_GETARG_DATUM(n))
+#define PG_RETURN_INT8(x)	 return Int8GetDatum(x)
+
+#endif

test/expected/functions.out

@@ -54,85 +54,85 @@ SELECT vector_norm('[3e37,4e37]')::real;
        5e+37
 (1 row)
 
-SELECT l2_distance('[0,0]', '[3,4]');
+SELECT l2_distance('[0,0]'::vector, '[3,4]');
  l2_distance 
 -------------
            5
 (1 row)
 
-SELECT l2_distance('[0,0]', '[0,1]');
+SELECT l2_distance('[0,0]'::vector, '[0,1]');
  l2_distance 
 -------------
            1
 (1 row)
 
-SELECT l2_distance('[1,2]', '[3]');
+SELECT l2_distance('[1,2]'::vector, '[3]');
 ERROR:  different vector dimensions 2 and 1
-SELECT l2_distance('[3e38]', '[-3e38]');
+SELECT l2_distance('[3e38]'::vector, '[-3e38]');
  l2_distance 
 -------------
     Infinity
 (1 row)
 
-SELECT inner_product('[1,2]', '[3,4]');
+SELECT inner_product('[1,2]'::vector, '[3,4]');
  inner_product 
 ---------------
             11
 (1 row)
 
-SELECT inner_product('[1,2]', '[3]');
+SELECT inner_product('[1,2]'::vector, '[3]');
 ERROR:  different vector dimensions 2 and 1
-SELECT inner_product('[3e38]', '[3e38]');
+SELECT inner_product('[3e38]'::vector, '[3e38]');
  inner_product 
 ---------------
       Infinity
 (1 row)
 
-SELECT cosine_distance('[1,2]', '[2,4]');
+SELECT cosine_distance('[1,2]'::vector, '[2,4]');
  cosine_distance 
 -----------------
                0
 (1 row)
 
-SELECT cosine_distance('[1,2]', '[0,0]');
+SELECT cosine_distance('[1,2]'::vector, '[0,0]');
  cosine_distance 
 -----------------
              NaN
 (1 row)
 
-SELECT cosine_distance('[1,1]', '[1,1]');
+SELECT cosine_distance('[1,1]'::vector, '[1,1]');
  cosine_distance 
 -----------------
                0
 (1 row)
 
-SELECT cosine_distance('[1,0]', '[0,2]');
+SELECT cosine_distance('[1,0]'::vector, '[0,2]');
  cosine_distance 
 -----------------
                1
 (1 row)
 
-SELECT cosine_distance('[1,1]', '[-1,-1]');
+SELECT cosine_distance('[1,1]'::vector, '[-1,-1]');
  cosine_distance 
 -----------------
                2
 (1 row)
 
-SELECT cosine_distance('[1,2]', '[3]');
+SELECT cosine_distance('[1,2]'::vector, '[3]');
 ERROR:  different vector dimensions 2 and 1
-SELECT cosine_distance('[1,1]', '[1.1,1.1]');
+SELECT cosine_distance('[1,1]'::vector, '[1.1,1.1]');
  cosine_distance 
 -----------------
                0
 (1 row)
 
-SELECT cosine_distance('[1,1]', '[-1.1,-1.1]');
+SELECT cosine_distance('[1,1]'::vector, '[-1.1,-1.1]');
  cosine_distance 
 -----------------
                2
 (1 row)
 
-SELECT cosine_distance('[3e38]', '[3e38]');
+SELECT cosine_distance('[3e38]'::vector, '[3e38]');
  cosine_distance 
 -----------------
              NaN

test/expected/tinyint.out

@@ -0,0 +1,148 @@
+SELECT '127'::tinyint;
+ tinyint 
+---------
+ 127
+(1 row)
+
+SELECT '128'::tinyint;
+ERROR:  value "128" is out of range for type tinyint
+LINE 1: SELECT '128'::tinyint;
+               ^
+SELECT '-128'::tinyint;
+ tinyint 
+---------
+ -128
+(1 row)
+
+SELECT '-129'::tinyint;
+ERROR:  value "-129" is out of range for type tinyint
+LINE 1: SELECT '-129'::tinyint;
+               ^
+SELECT ''::tinyint;
+ERROR:  invalid input syntax for type tinyint: ""
+LINE 1: SELECT ''::tinyint;
+               ^
+SELECT ' 1'::tinyint;
+ tinyint 
+---------
+ 1
+(1 row)
+
+SELECT '1 '::tinyint;
+ tinyint 
+---------
+ 1
+(1 row)
+
+SELECT '1a'::tinyint;
+ERROR:  invalid input syntax for type tinyint: "1a"
+LINE 1: SELECT '1a'::tinyint;
+               ^
+SELECT '{1,2,3}'::tinyint[];
+ tinyint 
+---------
+ {1,2,3}
+(1 row)
+
+SELECT '128'::numeric::tinyint;
+ERROR:  value "128" is out of range for type tinyint
+SELECT 'NaN'::numeric::tinyint;
+ERROR:  cannot convert NaN to integer
+SELECT l2_distance('{0,0}'::tinyint[], '{3,4}'::tinyint[]);
+ l2_distance 
+-------------
+           5
+(1 row)
+
+SELECT l2_distance('{0,0}'::tinyint[], '{0,1}'::tinyint[]);
+ l2_distance 
+-------------
+           1
+(1 row)
+
+SELECT l2_distance('{1,2}'::tinyint[], '{3}'::tinyint[]);
+ l2_distance 
+-------------
+            
+(1 row)
+
+SELECT l2_distance('{3e38}'::tinyint[], '{-3e38}'::tinyint[]);
+ERROR:  invalid input syntax for type tinyint: "3e38"
+LINE 1: SELECT l2_distance('{3e38}'::tinyint[], '{-3e38}'::tinyint[]...
+                           ^
+SELECT '{0,0}'::tinyint[] <-> '{3,4}'::tinyint[];
+ ?column? 
+----------
+        5
+(1 row)
+
+SELECT inner_product('{1,2}'::tinyint[], '{3,4}'::tinyint[]);
+ inner_product 
+---------------
+            11
+(1 row)
+
+SELECT inner_product('{1,2}'::tinyint[], '{3}'::tinyint[]);
+ inner_product 
+---------------
+              
+(1 row)
+
+SELECT inner_product('{127}'::tinyint[], '{127}'::tinyint[]);
+ inner_product 
+---------------
+         16129
+(1 row)
+
+SELECT '{1,2}'::tinyint[] <#> '{3,4}'::tinyint[];
+ ?column? 
+----------
+      -11
+(1 row)
+
+SELECT cosine_distance('{1,2}'::tinyint[], '{2,4}'::tinyint[]);
+ cosine_distance 
+-----------------
+               0
+(1 row)
+
+SELECT cosine_distance('{1,2}'::tinyint[], '{0,0}'::tinyint[]);
+ cosine_distance 
+-----------------
+             NaN
+(1 row)
+
+SELECT cosine_distance('{1,1}'::tinyint[], '{1,1}'::tinyint[]);
+ cosine_distance 
+-----------------
+               0
+(1 row)
+
+SELECT cosine_distance('{1,0}'::tinyint[], '{0,2}'::tinyint[]);
+ cosine_distance 
+-----------------
+               1
+(1 row)
+
+SELECT cosine_distance('{1,1}'::tinyint[], '{-1,-1}'::tinyint[]);
+ cosine_distance 
+-----------------
+               2
+(1 row)
+
+SELECT cosine_distance('{1,2}'::tinyint[], '{3}'::tinyint[]);
+ cosine_distance 
+-----------------
+                
+(1 row)
+
+SELECT cosine_distance('{3e38}'::tinyint[], '{3e38}'::tinyint[]);
+ERROR:  invalid input syntax for type tinyint: "3e38"
+LINE 1: SELECT cosine_distance('{3e38}'::tinyint[], '{3e38}'::tinyin...
+                               ^
+SELECT '{1,2}'::tinyint[] <=> '{2,4}'::tinyint[];
+ ?column? 
+----------
+        0
+(1 row)
+

test/sql/functions.sql

@@ -13,24 +13,24 @@ SELECT vector_norm('[3,4]');
 SELECT vector_norm('[0,1]');
 SELECT vector_norm('[3e37,4e37]')::real;
 
-SELECT l2_distance('[0,0]', '[3,4]');
+SELECT l2_distance('[0,0]'::vector, '[3,4]');
-SELECT l2_distance('[0,0]', '[0,1]');
+SELECT l2_distance('[0,0]'::vector, '[0,1]');
-SELECT l2_distance('[1,2]', '[3]');
+SELECT l2_distance('[1,2]'::vector, '[3]');
-SELECT l2_distance('[3e38]', '[-3e38]');
+SELECT l2_distance('[3e38]'::vector, '[-3e38]');
 
-SELECT inner_product('[1,2]', '[3,4]');
+SELECT inner_product('[1,2]'::vector, '[3,4]');
-SELECT inner_product('[1,2]', '[3]');
+SELECT inner_product('[1,2]'::vector, '[3]');
-SELECT inner_product('[3e38]', '[3e38]');
+SELECT inner_product('[3e38]'::vector, '[3e38]');
 
-SELECT cosine_distance('[1,2]', '[2,4]');
+SELECT cosine_distance('[1,2]'::vector, '[2,4]');
-SELECT cosine_distance('[1,2]', '[0,0]');
+SELECT cosine_distance('[1,2]'::vector, '[0,0]');
-SELECT cosine_distance('[1,1]', '[1,1]');
+SELECT cosine_distance('[1,1]'::vector, '[1,1]');
-SELECT cosine_distance('[1,0]', '[0,2]');
+SELECT cosine_distance('[1,0]'::vector, '[0,2]');
-SELECT cosine_distance('[1,1]', '[-1,-1]');
+SELECT cosine_distance('[1,1]'::vector, '[-1,-1]');
-SELECT cosine_distance('[1,2]', '[3]');
+SELECT cosine_distance('[1,2]'::vector, '[3]');
-SELECT cosine_distance('[1,1]', '[1.1,1.1]');
+SELECT cosine_distance('[1,1]'::vector, '[1.1,1.1]');
-SELECT cosine_distance('[1,1]', '[-1.1,-1.1]');
+SELECT cosine_distance('[1,1]'::vector, '[-1.1,-1.1]');
-SELECT cosine_distance('[3e38]', '[3e38]');
+SELECT cosine_distance('[3e38]'::vector, '[3e38]');
 
 SELECT l1_distance('[0,0]', '[3,4]');
 SELECT l1_distance('[0,0]', '[0,1]');

test/sql/tinyint.sql

@@ -0,0 +1,34 @@
+SELECT '127'::tinyint;
+SELECT '128'::tinyint;
+SELECT '-128'::tinyint;
+SELECT '-129'::tinyint;
+
+SELECT ''::tinyint;
+SELECT ' 1'::tinyint;
+SELECT '1 '::tinyint;
+SELECT '1a'::tinyint;
+
+SELECT '{1,2,3}'::tinyint[];
+
+SELECT '128'::numeric::tinyint;
+SELECT 'NaN'::numeric::tinyint;
+
+SELECT l2_distance('{0,0}'::tinyint[], '{3,4}'::tinyint[]);
+SELECT l2_distance('{0,0}'::tinyint[], '{0,1}'::tinyint[]);
+SELECT l2_distance('{1,2}'::tinyint[], '{3}'::tinyint[]);
+SELECT l2_distance('{3e38}'::tinyint[], '{-3e38}'::tinyint[]);
+SELECT '{0,0}'::tinyint[] <-> '{3,4}'::tinyint[];
+
+SELECT inner_product('{1,2}'::tinyint[], '{3,4}'::tinyint[]);
+SELECT inner_product('{1,2}'::tinyint[], '{3}'::tinyint[]);
+SELECT inner_product('{127}'::tinyint[], '{127}'::tinyint[]);
+SELECT '{1,2}'::tinyint[] <#> '{3,4}'::tinyint[];
+
+SELECT cosine_distance('{1,2}'::tinyint[], '{2,4}'::tinyint[]);
+SELECT cosine_distance('{1,2}'::tinyint[], '{0,0}'::tinyint[]);
+SELECT cosine_distance('{1,1}'::tinyint[], '{1,1}'::tinyint[]);
+SELECT cosine_distance('{1,0}'::tinyint[], '{0,2}'::tinyint[]);
+SELECT cosine_distance('{1,1}'::tinyint[], '{-1,-1}'::tinyint[]);
+SELECT cosine_distance('{1,2}'::tinyint[], '{3}'::tinyint[]);
+SELECT cosine_distance('{3e38}'::tinyint[], '{3e38}'::tinyint[]);
+SELECT '{1,2}'::tinyint[] <=> '{2,4}'::tinyint[];