Added subscript function for vectors

CHANGELOG.md

@@ -1,11 +1,15 @@
-## 0.6.2 (2024-03-18)
+## 0.7.0 (unreleased)
+
+- Added subscript function for vectors
+
+## 0.6.2 (unreleased)
 
 - Reduced lock contention with parallel HNSW index builds
 
 ## 0.6.1 (2024-03-04)
 
 - Fixed error with `ANALYZE` and vectors with different dimensions
-- Fixed segmentation fault with `shared_preload_libraries`
+- Fixed error with `shared_preload_libraries`
 - Fixed vector subtraction being marked as commutative
 
 ## 0.6.0 (2024-01-29)

META.json

@@ -2,7 +2,7 @@
 	"name": "vector",
 	"abstract": "Open-source vector similarity search for Postgres",
 	"description": "Supports L2 distance, inner product, and cosine distance",
-	"version": "0.6.2",
+	"version": "0.6.1",
 	"maintainer": [
 		"Andrew Kane <andrew@ankane.org>"
 	],
@@ -20,7 +20,7 @@
 		"vector": {
 			"file": "sql/vector.sql",
 			"docfile": "README.md",
-			"version": "0.6.2",
+			"version": "0.6.1",
 			"abstract": "Open-source vector similarity search for Postgres"
 		}
 	},

Makefile

@@ -1,5 +1,5 @@
 EXTENSION = vector
-EXTVERSION = 0.6.2
+EXTVERSION = 0.6.1
 
 MODULE_big = vector
 DATA = $(wildcard sql/*--*.sql)
@@ -10,15 +10,21 @@ TESTS = $(wildcard test/sql/*.sql)
 REGRESS = $(patsubst test/sql/%.sql,%,$(TESTS))
 REGRESS_OPTS = --inputdir=test --load-extension=$(EXTENSION)
 
-OPTFLAGS =
+OPTFLAGS = -march=native
 
-# Since runtime dispatch not supported
+# Mac ARM doesn't support -march=native
 ifeq ($(shell uname -s), Darwin)
-	ifeq ($(shell uname -m), x86_64)
+	ifeq ($(shell uname -p), arm)
-		OPTFLAGS = -march=native
+		# no difference with -march=armv8.5-a
+		OPTFLAGS =
 	endif
 endif
 
+# PowerPC doesn't support -march=native
+ifneq ($(filter ppc64%, $(shell uname -m)), )
+	OPTFLAGS =
+endif
+
 # For auto-vectorization:
 # - GCC (needs -ftree-vectorize OR -O3) - https://gcc.gnu.org/projects/tree-ssa/vectorization.html
 # - Clang (could use pragma instead) - https://llvm.org/docs/Vectorizers.html

Makefile.win

@@ -1,5 +1,5 @@
 EXTENSION = vector
-EXTVERSION = 0.6.2
+EXTVERSION = 0.6.1
 
 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
 HEADERS = src\vector.h

README.md

@@ -20,7 +20,7 @@ Compile and install the extension (supports Postgres 12+)
 
 ```sh
 cd /tmp
-git clone --branch v0.6.2 https://github.com/pgvector/pgvector.git
+git clone --branch v0.6.1 https://github.com/pgvector/pgvector.git
 cd pgvector
 make
 make install # may need sudo
@@ -45,7 +45,7 @@ Then use `nmake` to build:
 ```cmd
 set "PGROOT=C:\Program Files\PostgreSQL\16"
 cd %TEMP%
-git clone --branch v0.6.2 https://github.com/pgvector/pgvector.git
+git clone --branch v0.6.1 https://github.com/pgvector/pgvector.git
 cd pgvector
 nmake /F Makefile.win
 nmake /F Makefile.win install
@@ -604,18 +604,6 @@ and query with:
 SELECT * FROM items ORDER BY embedding::vector(3) <-> '[3,1,2]' LIMIT 5;
 ```
 
-#### Are binary vectors supported?
-
-You can store binary vectors and perform exact nearest neighbor search by Hamming distance in Postgres without an extension ([example](https://github.com/pgvector/pgvector-python/blob/master/examples/hash_image_search.py)).
-
-```tsql
-CREATE TABLE items (id bigserial PRIMARY KEY, embedding bit(3));
-INSERT INTO items (embedding) VALUES (B'000'), (B'111');
-SELECT * FROM items ORDER BY bit_count(embedding # B'101') LIMIT 5;
-```
-
-Indexing is not currently supported.
-
 #### Do indexes need to fit into memory?
 
 No, but like other index types, you’ll likely see better performance if they do. You can get the size of an index with:
@@ -671,8 +659,6 @@ ALTER TABLE items ALTER COLUMN embedding SET STORAGE PLAIN;
 
 Results are limited by the size of the dynamic candidate list (`hnsw.ef_search`). There may be even less results due to dead tuples or filtering conditions in the query. We recommend setting `hnsw.ef_search` to at least twice the `LIMIT` of the query. If you need more than 500 results, use an IVFFlat index instead.
 
-Also, note that `NULL` vectors are not indexed (as well as zero vectors for cosine distance).
-
 #### Why are there less results for a query after adding an IVFFlat index?
 
 The index was likely created with too little data for the number of lists. Drop the index until the table has more data.
@@ -683,13 +669,11 @@ DROP INDEX index_name;
 
 Results can also be limited by the number of probes (`ivfflat.probes`).
 
-Also, note that `NULL` vectors are not indexed (as well as zero vectors for cosine distance).
-
 ## Reference
 
 ### Vector Type
 
-Each vector takes `4 * dimensions + 8` bytes of storage. Each element is a single-precision floating-point number (like the `real` type in Postgres), and all elements must be finite (no `NaN`, `Infinity` or `-Infinity`). Vectors can have up to 16,000 dimensions.
+Each vector takes `4 * dimensions + 8` bytes of storage. Each element is a single precision floating-point number (like the `real` type in Postgres), and all elements must be finite (no `NaN`, `Infinity` or `-Infinity`). Vectors can have up to 16,000 dimensions.
 
 ### Vector Operators
 
@@ -713,7 +697,7 @@ l1_distance(vector, vector) → double precision | taxicab distance | 0.5.0
 vector_dims(vector) → integer | number of dimensions |
 vector_norm(vector) → double precision | Euclidean norm |
 
-### Vector Aggregate Functions
+### Aggregate Functions
 
 Function | Description | Added
 --- | --- | ---
@@ -795,7 +779,7 @@ This adds pgvector to the [Postgres image](https://hub.docker.com/_/postgres) (r
 You can also build the image manually:
 
 ```sh
-git clone --branch v0.6.2 https://github.com/pgvector/pgvector.git
+git clone --branch v0.6.1 https://github.com/pgvector/pgvector.git
 cd pgvector
 docker build --build-arg PG_MAJOR=16 -t myuser/pgvector .
 ```

sql/vector--0.6.1--0.6.2.sql

@@ -1,2 +0,0 @@
--- complain if script is sourced in psql, rather than via CREATE EXTENSION
-\echo Use "ALTER EXTENSION vector UPDATE TO '0.6.2'" to load this file. \quit

sql/vector--0.6.2--0.7.0.sql

@@ -0,0 +1,7 @@
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "ALTER EXTENSION vector UPDATE TO '0.7.0'" to load this file. \quit
+
+CREATE FUNCTION vector_subscript(internal) RETURNS internal
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+ALTER TYPE vector SET (SUBSCRIPT = vector_subscript);

sql/vector.sql

@@ -20,12 +20,16 @@ CREATE FUNCTION vector_recv(internal, oid, integer) RETURNS vector
 CREATE FUNCTION vector_send(vector) RETURNS bytea
 	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
 
+CREATE FUNCTION vector_subscript(internal) RETURNS internal
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
 CREATE TYPE vector (
 	INPUT     = vector_in,
 	OUTPUT    = vector_out,
 	TYPMOD_IN = vector_typmod_in,
 	RECEIVE   = vector_recv,
 	SEND      = vector_send,
+	SUBSCRIPT = vector_subscript,
 	STORAGE   = external
 );
 

src/hnsw.h

@@ -262,6 +262,7 @@ typedef struct HnswBuildState
 	HnswGraph  *graph;
 	double		ml;
 	int			maxLevel;
+	Vector	   *normvec;
 
 	/* Memory */
 	MemoryContext graphCtx;
@@ -366,7 +367,7 @@ typedef struct HnswVacuumState
 int			HnswGetM(Relation index);
 int			HnswGetEfConstruction(Relation index);
 FmgrInfo   *HnswOptionalProcInfo(Relation index, uint16 procnum);
-bool		HnswNormValue(FmgrInfo *procinfo, Oid collation, Datum *value);
+bool		HnswNormValue(FmgrInfo *procinfo, Oid collation, Datum *value, Vector * result);
 Buffer		HnswNewBuffer(Relation index, ForkNumber forkNum);
 void		HnswInitPage(Buffer buf, Page page);
 void		HnswInit(void);

src/hnswbuild.c

@@ -489,7 +489,7 @@ InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heaptid, Hn
 	/* Normalize if needed */
 	if (buildstate->normprocinfo != NULL)
 	{
-		if (!HnswNormValue(buildstate->normprocinfo, buildstate->collation, &value))
+		if (!HnswNormValue(buildstate->normprocinfo, buildstate->collation, &value, buildstate->normvec))
 			return false;
 	}
 
@@ -703,6 +703,9 @@ InitBuildState(HnswBuildState * buildstate, Relation heap, Relation index, Index
 	buildstate->ml = HnswGetMl(buildstate->m);
 	buildstate->maxLevel = HnswGetMaxLevel(buildstate->m);
 
+	/* Reuse for each tuple */
+	buildstate->normvec = InitVector(buildstate->dimensions);
+
 	buildstate->graphCtx = GenerationContextCreate(CurrentMemoryContext,
 												   "Hnsw build graph context",
 #if PG_VERSION_NUM >= 150000
@@ -726,6 +729,7 @@ InitBuildState(HnswBuildState * buildstate, Relation heap, Relation index, Index
 static void
 FreeBuildState(HnswBuildState * buildstate)
 {
+	pfree(buildstate->normvec);
 	MemoryContextDelete(buildstate->graphCtx);
 	MemoryContextDelete(buildstate->tmpCtx);
 }

src/hnswinsert.c

@@ -622,7 +622,7 @@ HnswInsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heap_ti
 	normprocinfo = HnswOptionalProcInfo(index, HNSW_NORM_PROC);
 	if (normprocinfo != NULL)
 	{
-		if (!HnswNormValue(normprocinfo, collation, &value))
+		if (!HnswNormValue(normprocinfo, collation, &value, NULL))
 			return;
 	}
 

src/hnswscan.c

@@ -84,7 +84,7 @@ GetScanValue(IndexScanDesc scan)
 
 		/* Fine if normalization fails */
 		if (so->normprocinfo != NULL)
-			HnswNormValue(so->normprocinfo, so->collation, &value);
+			HnswNormValue(so->normprocinfo, so->collation, &value, NULL);
 	}
 
 	return value;

src/hnswutils.c

@@ -158,14 +158,16 @@ HnswOptionalProcInfo(Relation index, uint16 procnum)
  * if it's different than the original value
  */
 bool
-HnswNormValue(FmgrInfo *procinfo, Oid collation, Datum *value)
+HnswNormValue(FmgrInfo *procinfo, Oid collation, Datum *value, Vector * result)
 {
 	double		norm = DatumGetFloat8(FunctionCall1Coll(procinfo, collation, *value));
 
 	if (norm > 0)
 	{
 		Vector	   *v = DatumGetVector(*value);
-		Vector	   *result = InitVector(v->dim);
+
+		if (result == NULL)
+			result = InitVector(v->dim);
 
 		for (int i = 0; i < v->dim; i++)
 			result->x[i] = v->x[i] / norm;

src/ivfbuild.c

@@ -57,7 +57,7 @@ AddSample(Datum *values, IvfflatBuildState * buildstate)
 	 */
 	if (buildstate->kmeansnormprocinfo != NULL)
 	{
-		if (!IvfflatNormValue(buildstate->kmeansnormprocinfo, buildstate->collation, &value))
+		if (!IvfflatNormValue(buildstate->kmeansnormprocinfo, buildstate->collation, &value, buildstate->normvec))
 			return;
 	}
 
@@ -153,7 +153,7 @@ AddTupleToSort(Relation index, ItemPointer tid, Datum *values, IvfflatBuildState
 	/* Normalize if needed */
 	if (buildstate->normprocinfo != NULL)
 	{
-		if (!IvfflatNormValue(buildstate->normprocinfo, buildstate->collation, &value))
+		if (!IvfflatNormValue(buildstate->normprocinfo, buildstate->collation, &value, buildstate->normvec))
 			return;
 	}
 
@@ -356,6 +356,9 @@ InitBuildState(IvfflatBuildState * buildstate, Relation heap, Relation index, In
 	buildstate->centers = VectorArrayInit(buildstate->lists, buildstate->dimensions);
 	buildstate->listInfo = palloc(sizeof(ListInfo) * buildstate->lists);
 
+	/* Reuse for each tuple */
+	buildstate->normvec = InitVector(buildstate->dimensions);
+
 	buildstate->tmpCtx = AllocSetContextCreate(CurrentMemoryContext,
 											   "Ivfflat build temporary context",
 											   ALLOCSET_DEFAULT_SIZES);
@@ -377,6 +380,7 @@ FreeBuildState(IvfflatBuildState * buildstate)
 {
 	VectorArrayFree(buildstate->centers);
 	pfree(buildstate->listInfo);
+	pfree(buildstate->normvec);
 
 #ifdef IVFFLAT_KMEANS_DEBUG
 	pfree(buildstate->listSums);

src/ivfflat.h

@@ -172,6 +172,7 @@ typedef struct IvfflatBuildState
 	VectorArray samples;
 	VectorArray centers;
 	ListInfo   *listInfo;
+	Vector	   *normvec;
 
 #ifdef IVFFLAT_KMEANS_DEBUG
 	double		inertia;
@@ -266,7 +267,7 @@ void		VectorArrayFree(VectorArray arr);
 void		PrintVectorArray(char *msg, VectorArray arr);
 void		IvfflatKmeans(Relation index, VectorArray samples, VectorArray centers);
 FmgrInfo   *IvfflatOptionalProcInfo(Relation index, uint16 procnum);
-bool		IvfflatNormValue(FmgrInfo *procinfo, Oid collation, Datum *value);
+bool		IvfflatNormValue(FmgrInfo *procinfo, Oid collation, Datum *value, Vector * result);
 int			IvfflatGetLists(Relation index);
 void		IvfflatGetMetaPageInfo(Relation index, int *lists, int *dimensions);
 void		IvfflatUpdateList(Relation index, ListInfo listInfo, BlockNumber insertPage, BlockNumber originalInsertPage, BlockNumber startPage, ForkNumber forkNum);

src/ivfinsert.c

@@ -85,7 +85,7 @@ InsertTuple(Relation index, Datum *values, bool *isnull, ItemPointer heap_tid, R
 	normprocinfo = IvfflatOptionalProcInfo(index, IVFFLAT_NORM_PROC);
 	if (normprocinfo != NULL)
 	{
-		if (!IvfflatNormValue(normprocinfo, index->rd_indcollation[0], &value))
+		if (!IvfflatNormValue(normprocinfo, index->rd_indcollation[0], &value, NULL))
 			return;
 	}
 

src/ivfscan.c

@@ -293,7 +293,7 @@ ivfflatgettuple(IndexScanDesc scan, ScanDirection dir)
 
 			/* Fine if normalization fails */
 			if (so->normprocinfo != NULL)
-				IvfflatNormValue(so->normprocinfo, so->collation, &value);
+				IvfflatNormValue(so->normprocinfo, so->collation, &value, NULL);
 		}
 
 		IvfflatBench("GetScanLists", GetScanLists(scan, value));

src/ivfutils.c

@@ -75,14 +75,16 @@ IvfflatOptionalProcInfo(Relation index, uint16 procnum)
  * if it's different than the original value
  */
 bool
-IvfflatNormValue(FmgrInfo *procinfo, Oid collation, Datum *value)
+IvfflatNormValue(FmgrInfo *procinfo, Oid collation, Datum *value, Vector * result)
 {
 	double		norm = DatumGetFloat8(FunctionCall1Coll(procinfo, collation, *value));
 
 	if (norm > 0)
 	{
 		Vector	   *v = DatumGetVector(*value);
-		Vector	   *result = InitVector(v->dim);
+
+		if (result == NULL)
+			result = InitVector(v->dim);
 
 		for (int i = 0; i < v->dim; i++)
 			result->x[i] = v->x[i] / norm;

src/vector.c

@@ -4,11 +4,18 @@
 
 #include "catalog/pg_type.h"
 #include "common/shortest_dec.h"
+#include "executor/execExpr.h"
 #include "fmgr.h"
 #include "hnsw.h"
 #include "ivfflat.h"
 #include "lib/stringinfo.h"
 #include "libpq/pqformat.h"
+#include "nodes/makefuncs.h"
+#include "nodes/nodeFuncs.h"
+#include "nodes/subscripting.h"
+#include "parser/parse_coerce.h"
+#include "parser/parse_expr.h"
+#include "parser/parse_node.h"
 #include "port.h"				/* for strtof() */
 #include "utils/array.h"
 #include "utils/builtins.h"
@@ -29,15 +36,6 @@
 #define STATE_DIMS(x) (ARR_DIMS(x)[0] - 1)
 #define CreateStateDatums(dim) palloc(sizeof(Datum) * (dim + 1))
 
-#if defined(__x86_64__) && defined(__gnu_linux__) && defined(__has_attribute) && __has_attribute(target_clones)
-#define RUNTIME_DISPATCH __attribute__((target_clones("default", "avx", "fma", "avx512f")))
-#elif defined(__aarch64__) && defined(__gnu_linux__) && defined(__has_attribute) && __has_attribute(target_clones)
-/* TODO Fix error: target does not support function version dispatcher */
-#define RUNTIME_DISPATCH __attribute__((target_clones("default", "arch=armv8.5-a")))
-#else
-#define RUNTIME_DISPATCH
-#endif
-
 PG_MODULE_MAGIC;
 
 /*
@@ -427,6 +425,180 @@ vector_send(PG_FUNCTION_ARGS)
 	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
 }
 
+/*
+ * Transform the subscript expressions
+ */
+static void
+vector_subscript_transform(SubscriptingRef *sbsref, List *indirection, ParseState *pstate, bool isSlice, bool isAssignment)
+{
+	A_Indices  *ai;
+	Node	   *subexpr;
+
+	if (list_length(indirection) != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("vector allows only one subscript"),
+				 parser_errposition(pstate,
+									exprLocation((Node *) indirection))));
+
+	ai = linitial_node(A_Indices, indirection);
+
+	if (isSlice)
+	{
+		if (ai->lidx)
+		{
+			subexpr = transformExpr(pstate, ai->lidx, pstate->p_expr_kind);
+			/* If it's not int4 already, try to coerce */
+			subexpr = coerce_to_target_type(pstate,
+											subexpr, exprType(subexpr),
+											INT4OID, -1,
+											COERCION_ASSIGNMENT,
+											COERCE_IMPLICIT_CAST,
+											-1);
+			if (subexpr == NULL)
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("vector subscript must have type integer"),
+						 parser_errposition(pstate, exprLocation(ai->lidx))));
+		}
+		else if (!ai->is_slice)
+		{
+			/* Make a constant 1 */
+			subexpr = (Node *) makeConst(INT4OID,
+										 -1,
+										 InvalidOid,
+										 sizeof(int32),
+										 Int32GetDatum(1),
+										 false,
+										 true); /* pass by value */
+		}
+		else
+		{
+			/* Slice with omitted lower bound, put NULL into the list */
+			subexpr = NULL;
+		}
+		sbsref->reflowerindexpr = list_make1(subexpr);
+	}
+	else
+		Assert(ai->lidx == NULL && !ai->is_slice);
+
+	if (ai->uidx)
+	{
+		subexpr = transformExpr(pstate, ai->uidx, pstate->p_expr_kind);
+		/* If it's not int4 already, try to coerce */
+		subexpr = coerce_to_target_type(pstate,
+										subexpr, exprType(subexpr),
+										INT4OID, -1,
+										COERCION_ASSIGNMENT,
+										COERCE_IMPLICIT_CAST,
+										-1);
+		if (subexpr == NULL)
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("array subscript must have type integer"),
+					 parser_errposition(pstate, exprLocation(ai->uidx))));
+	}
+	else
+	{
+		/* Slice with omitted upper bound, put NULL into the list */
+		Assert(isSlice && ai->is_slice);
+		subexpr = NULL;
+	}
+	sbsref->refupperindexpr = list_make1(subexpr);
+
+	if (isSlice)
+		sbsref->refrestype = sbsref->refcontainertype;
+	else
+		sbsref->refrestype = FLOAT4OID;
+}
+
+/*
+ * Fetch a vector element
+ */
+static void
+vector_subscript_fetch(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
+{
+	SubscriptingRefState *sbsrefstate = op->d.sbsref.state;
+	Vector	   *vec = DatumGetVector(*op->resvalue);
+	int			index = DatumGetInt32(sbsrefstate->upperindex[0]);
+
+	if (index < 1 || index > vec->dim)
+		*op->resnull = true;
+	else
+		*op->resvalue = Float4GetDatum(vec->x[index - 1]);
+}
+
+/*
+ * Fetch a vector slice
+ */
+static void
+vector_subscript_fetch_slice(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
+{
+	SubscriptingRefState *sbsrefstate = op->d.sbsref.state;
+
+	if (sbsrefstate->upperprovided[0] && sbsrefstate->upperindexnull[0])
+		*op->resnull = true;
+	else if (sbsrefstate->lowerprovided[0] && sbsrefstate->lowerindexnull[0])
+		*op->resnull = true;
+	else
+	{
+		Vector	   *vec = DatumGetVector(*op->resvalue);
+		int			upperindex = sbsrefstate->upperprovided[0] ? DatumGetInt32(sbsrefstate->upperindex[0]) : vec->dim;
+		int			lowerindex = sbsrefstate->lowerprovided[0] ? DatumGetInt32(sbsrefstate->lowerindex[0]) : 1;
+		int			dim;
+		Vector	   *result;
+
+		if (upperindex > vec->dim)
+			upperindex = vec->dim;
+
+		if (lowerindex < 1)
+			lowerindex = 1;
+
+		dim = upperindex - lowerindex + 1;
+
+		CheckDim(dim);
+
+		result = InitVector(dim);
+		for (int i = 0; i < dim; i++)
+			result->x[i] = vec->x[lowerindex + i - 1];
+
+		*op->resvalue = PointerGetDatum(result);
+	}
+}
+
+/*
+ * Set up execution state for a vector subscript operation
+ */
+static void
+vector_exec_setup(const SubscriptingRef *sbsref, SubscriptingRefState *sbsrefstate, SubscriptExecSteps *methods)
+{
+	methods->sbs_check_subscripts = NULL;
+	if (sbsrefstate->numlower != 0)
+		methods->sbs_fetch = vector_subscript_fetch_slice;
+	else
+		methods->sbs_fetch = vector_subscript_fetch;
+	methods->sbs_assign = NULL;
+	methods->sbs_fetch_old = NULL;
+}
+
+/*
+ * Subscript handler
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(vector_subscript);
+Datum
+vector_subscript(PG_FUNCTION_ARGS)
+{
+	static const SubscriptRoutines sbsroutines = {
+		.transform = vector_subscript_transform,
+		.exec_setup = vector_exec_setup,
+		.fetch_strict = true,	/* fetch returns NULL for NULL inputs */
+		.fetch_leakproof = true,	/* fetch returns NULL for bad subscript */
+		.store_leakproof = false	/* ... but assignment throws error */
+	};
+
+	PG_RETURN_POINTER(&sbsroutines);
+}
+
 /*
  * Convert vector to vector
  * This is needed to check the type modifier
@@ -541,23 +713,6 @@ vector_to_float4(PG_FUNCTION_ARGS)
 	PG_RETURN_POINTER(result);
 }
 
-RUNTIME_DISPATCH
-static float
-l2_squared_distance_impl(int16 dim, float *ax, float *bx)
-{
-	float		distance = 0.0;
-
-	/* Auto-vectorized */
-	for (int16 i = 0; i < dim; i++)
-	{
-		float		diff = ax[i] - bx[i];
-
-		distance += diff * diff;
-	}
-
-	return distance;
-}
-
 /*
  * Get the L2 distance between vectors
  */
@@ -567,11 +722,19 @@ l2_distance(PG_FUNCTION_ARGS)
 {
 	Vector	   *a = PG_GETARG_VECTOR_P(0);
 	Vector	   *b = PG_GETARG_VECTOR_P(1);
-	float		distance;
+	float	   *ax = a->x;
+	float	   *bx = b->x;
+	float		distance = 0.0;
+	float		diff;
 
 	CheckDims(a, b);
 
-	distance = l2_squared_distance_impl(a->dim, a->x, b->x);
+	/* Auto-vectorized */
+	for (int i = 0; i < a->dim; i++)
+	{
+		diff = ax[i] - bx[i];
+		distance += diff * diff;
+	}
 
 	PG_RETURN_FLOAT8(sqrt((double) distance));
 }
@@ -586,11 +749,19 @@ vector_l2_squared_distance(PG_FUNCTION_ARGS)
 {
 	Vector	   *a = PG_GETARG_VECTOR_P(0);
 	Vector	   *b = PG_GETARG_VECTOR_P(1);
-	float		distance;
+	float	   *ax = a->x;
+	float	   *bx = b->x;
+	float		distance = 0.0;
+	float		diff;
 
 	CheckDims(a, b);
 
-	distance = l2_squared_distance_impl(a->dim, a->x, b->x);
+	/* Auto-vectorized */
+	for (int i = 0; i < a->dim; i++)
+	{
+		diff = ax[i] - bx[i];
+		distance += diff * diff;
+	}
 
 	PG_RETURN_FLOAT8((double) distance);
 }

test/expected/functions.out

@@ -24,6 +24,112 @@ SELECT '[1e37]'::vector * '[1e37]';
 ERROR:  value out of range: overflow
 SELECT '[1e-37]'::vector * '[1e-37]';
 ERROR:  value out of range: underflow
+SELECT ('[1,2,3]'::vector)[0];
+ vector 
+--------
+       
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[1];
+ vector 
+--------
+      1
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[2];
+ vector 
+--------
+      2
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[3];
+ vector 
+--------
+      3
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[4];
+ vector 
+--------
+       
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[1:1];
+ vector 
+--------
+ [1]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[1:2];
+ vector 
+--------
+ [1,2]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[2:4];
+ vector 
+--------
+ [2,3]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[-2:2];
+ vector 
+--------
+ [1,2]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[2:1];
+ERROR:  vector must have at least 1 dimension
+SELECT ('[1,2,3]'::vector)[:];
+ vector  
+---------
+ [1,2,3]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[:2];
+ vector 
+--------
+ [1,2]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[2:];
+ vector 
+--------
+ [2,3]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[:4];
+ vector  
+---------
+ [1,2,3]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[-2:];
+ vector  
+---------
+ [1,2,3]
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[NULL];
+ vector 
+--------
+       
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[NULL:2];
+ vector 
+--------
+ 
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[2:NULL];
+ vector 
+--------
+ 
+(1 row)
+
+SELECT ('[1,2,3]'::vector)[1][1];
+ERROR:  vector allows only one subscript
 SELECT '[1,2,3]'::vector = '[1,2,3]';
  ?column? 
 ----------

test/expected/input.out

@@ -116,30 +116,8 @@ SELECT '[1, ,3]'::vector;
 ERROR:  invalid input syntax for type vector: "[1, ,3]"
 LINE 1: SELECT '[1, ,3]'::vector;
                ^
-SELECT '[1,2,3]'::vector(3);
- vector  
----------
- [1,2,3]
-(1 row)
-
 SELECT '[1,2,3]'::vector(2);
 ERROR:  expected 2 dimensions, not 3
-SELECT '[1,2,3]'::vector(3, 2);
-ERROR:  invalid type modifier
-LINE 1: SELECT '[1,2,3]'::vector(3, 2);
-                          ^
-SELECT '[1,2,3]'::vector('a');
-ERROR:  invalid input syntax for type integer: "a"
-LINE 1: SELECT '[1,2,3]'::vector('a');
-                          ^
-SELECT '[1,2,3]'::vector(0);
-ERROR:  dimensions for type vector must be at least 1
-LINE 1: SELECT '[1,2,3]'::vector(0);
-                          ^
-SELECT '[1,2,3]'::vector(16001);
-ERROR:  dimensions for type vector cannot exceed 16000
-LINE 1: SELECT '[1,2,3]'::vector(16001);
-                          ^
 SELECT unnest('{"[1,2,3]", "[4,5,6]"}'::vector[]);
  unnest  
 ---------

test/sql/functions.sql

@@ -6,6 +6,26 @@ SELECT '[1,2,3]'::vector * '[4,5,6]';
 SELECT '[1e37]'::vector * '[1e37]';
 SELECT '[1e-37]'::vector * '[1e-37]';
 
+SELECT ('[1,2,3]'::vector)[0];
+SELECT ('[1,2,3]'::vector)[1];
+SELECT ('[1,2,3]'::vector)[2];
+SELECT ('[1,2,3]'::vector)[3];
+SELECT ('[1,2,3]'::vector)[4];
+SELECT ('[1,2,3]'::vector)[1:1];
+SELECT ('[1,2,3]'::vector)[1:2];
+SELECT ('[1,2,3]'::vector)[2:4];
+SELECT ('[1,2,3]'::vector)[-2:2];
+SELECT ('[1,2,3]'::vector)[2:1];
+SELECT ('[1,2,3]'::vector)[:];
+SELECT ('[1,2,3]'::vector)[:2];
+SELECT ('[1,2,3]'::vector)[2:];
+SELECT ('[1,2,3]'::vector)[:4];
+SELECT ('[1,2,3]'::vector)[-2:];
+SELECT ('[1,2,3]'::vector)[NULL];
+SELECT ('[1,2,3]'::vector)[NULL:2];
+SELECT ('[1,2,3]'::vector)[2:NULL];
+SELECT ('[1,2,3]'::vector)[1][1];
+
 SELECT '[1,2,3]'::vector = '[1,2,3]';
 SELECT '[1,2,3]'::vector = '[1,2]';
 

test/sql/input.sql

@@ -22,13 +22,7 @@ SELECT '[1,]'::vector;
 SELECT '[1a]'::vector;
 SELECT '[1,,3]'::vector;
 SELECT '[1, ,3]'::vector;
-
-SELECT '[1,2,3]'::vector(3);
 SELECT '[1,2,3]'::vector(2);
-SELECT '[1,2,3]'::vector(3, 2);
-SELECT '[1,2,3]'::vector('a');
-SELECT '[1,2,3]'::vector(0);
-SELECT '[1,2,3]'::vector(16001);
 
 SELECT unnest('{"[1,2,3]", "[4,5,6]"}'::vector[]);
 SELECT '{"[1,2,3]"}'::vector(2)[];

vector.control

@@ -1,4 +1,4 @@
 comment = 'vector data type and ivfflat and hnsw access methods'
-default_version = '0.6.2'
+default_version = '0.6.1'
 module_pathname = '$libdir/vector'
 relocatable = true