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hnsw-entry
| Author | SHA1 | Date | |
|---|---|---|---|
|
|
75cf54a1e2 | ||
|
|
569fd36396 |
1
.github/workflows/build.yml
vendored
1
.github/workflows/build.yml
vendored
@@ -73,7 +73,6 @@ jobs:
|
||||
postgres-version: 14
|
||||
- run: |
|
||||
call "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Auxiliary\Build\vcvars64.bat" && ^
|
||||
cd %TEMP% && ^
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||||
nmake /NOLOGO /F Makefile.win && ^
|
||||
nmake /NOLOGO /F Makefile.win install && ^
|
||||
nmake /NOLOGO /F Makefile.win installcheck && ^
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||||
|
||||
@@ -1,7 +1,3 @@
|
||||
## 0.7.0 (unreleased)
|
||||
|
||||
- Added subscript function for vectors
|
||||
|
||||
## 0.6.2 (unreleased)
|
||||
|
||||
- Reduced lock contention with parallel HNSW index builds
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||||
|
||||
110
README.md
110
README.md
@@ -26,7 +26,7 @@ make
|
||||
make install # may need sudo
|
||||
```
|
||||
|
||||
See the [installation notes](#installation-notes---linux-and-mac) if you run into issues
|
||||
See the [installation notes](#installation-notes) if you run into issues
|
||||
|
||||
You can also install it with [Docker](#docker), [Homebrew](#homebrew), [PGXN](#pgxn), [APT](#apt), [Yum](#yum), [pkg](#pkg), or [conda-forge](#conda-forge), and it comes preinstalled with [Postgres.app](#postgresapp) and many [hosted providers](#hosted-postgres). There are also instructions for [GitHub Actions](https://github.com/pgvector/setup-pgvector).
|
||||
|
||||
@@ -44,15 +44,12 @@ Then use `nmake` to build:
|
||||
|
||||
```cmd
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||||
set "PGROOT=C:\Program Files\PostgreSQL\16"
|
||||
cd %TEMP%
|
||||
git clone --branch v0.6.1 https://github.com/pgvector/pgvector.git
|
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cd pgvector
|
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nmake /F Makefile.win
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||||
nmake /F Makefile.win install
|
||||
```
|
||||
|
||||
See the [installation notes](#installation-notes---windows) if you run into issues
|
||||
|
||||
You can also install it with [Docker](#docker) or [conda-forge](#conda-forge).
|
||||
|
||||
## Getting Started
|
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@@ -413,39 +410,13 @@ You can use [Reciprocal Rank Fusion](https://github.com/pgvector/pgvector-python
|
||||
|
||||
## Performance
|
||||
|
||||
### Tuning
|
||||
|
||||
Use a tool like [PgTune](https://pgtune.leopard.in.ua/) to set initial values for Postgres server parameters.
|
||||
|
||||
### Loading
|
||||
|
||||
Use `COPY` for bulk loading data ([example](https://github.com/pgvector/pgvector-python/blob/master/examples/bulk_loading.py)).
|
||||
|
||||
```sql
|
||||
COPY items (embedding) FROM STDIN WITH (FORMAT BINARY);
|
||||
```
|
||||
|
||||
Add any indexes *after* loading the initial data for best performance.
|
||||
|
||||
### Indexing
|
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|
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See index build time for [HNSW](#index-build-time) and [IVFFlat](#index-build-time-1).
|
||||
|
||||
In production environments, create indexes concurrently to avoid blocking writes.
|
||||
|
||||
```sql
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CREATE INDEX CONCURRENTLY ...
|
||||
```
|
||||
|
||||
### Querying
|
||||
|
||||
Use `EXPLAIN ANALYZE` to debug performance.
|
||||
|
||||
```sql
|
||||
EXPLAIN ANALYZE SELECT * FROM items ORDER BY embedding <-> '[3,1,2]' LIMIT 5;
|
||||
```
|
||||
|
||||
#### Exact Search
|
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### Exact Search
|
||||
|
||||
To speed up queries without an index, increase `max_parallel_workers_per_gather`.
|
||||
|
||||
@@ -459,7 +430,7 @@ If vectors are normalized to length 1 (like [OpenAI embeddings](https://platform
|
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SELECT * FROM items ORDER BY embedding <#> '[3,1,2]' LIMIT 5;
|
||||
```
|
||||
|
||||
#### Approximate Search
|
||||
### Approximate Search
|
||||
|
||||
To speed up queries with an IVFFlat index, increase the number of inverted lists (at the expense of recall).
|
||||
|
||||
@@ -467,7 +438,7 @@ To speed up queries with an IVFFlat index, increase the number of inverted lists
|
||||
CREATE INDEX ON items USING ivfflat (embedding vector_l2_ops) WITH (lists = 1000);
|
||||
```
|
||||
|
||||
### Vacuuming
|
||||
## Vacuuming
|
||||
|
||||
Vacuuming can take a while for HNSW indexes. Speed it up by reindexing first.
|
||||
|
||||
@@ -476,41 +447,6 @@ REINDEX INDEX CONCURRENTLY index_name;
|
||||
VACUUM table_name;
|
||||
```
|
||||
|
||||
## Monitoring
|
||||
|
||||
Monitor performance with [pg_stat_statements](https://www.postgresql.org/docs/current/pgstatstatements.html) (be sure to add it to `shared_preload_libraries`).
|
||||
|
||||
```sql
|
||||
CREATE EXTENSION pg_stat_statements;
|
||||
```
|
||||
|
||||
Get the most time-consuming queries with:
|
||||
|
||||
```sql
|
||||
SELECT query, calls, ROUND((total_plan_time + total_exec_time) / calls) AS avg_time_ms,
|
||||
ROUND((total_plan_time + total_exec_time) / 60000) AS total_time_min
|
||||
FROM pg_stat_statements ORDER BY total_plan_time + total_exec_time DESC LIMIT 20;
|
||||
```
|
||||
|
||||
Note: Replace `total_plan_time + total_exec_time` with `total_time` for Postgres < 13
|
||||
|
||||
Monitor recall by comparing results from approximate search with exact search.
|
||||
|
||||
```sql
|
||||
BEGIN;
|
||||
SET LOCAL enable_indexscan = off; -- use exact search
|
||||
SELECT ...
|
||||
COMMIT;
|
||||
```
|
||||
|
||||
## Scaling
|
||||
|
||||
Scale pgvector the same way you scale Postgres.
|
||||
|
||||
Scale vertically by increasing memory, CPU, and storage on a single instance. Use existing tools to [tune parameters](#tuning) and [monitor performance](#monitoring).
|
||||
|
||||
Scale horizontally with [replicas](https://www.postgresql.org/docs/current/hot-standby.html), or use [Citus](https://github.com/citusdata/citus) or another approach for sharding ([example](https://github.com/pgvector/pgvector-python/blob/master/examples/citus.py)).
|
||||
|
||||
## Languages
|
||||
|
||||
Use pgvector from any language with a Postgres client. You can even generate and store vectors in one language and query them in another.
|
||||
@@ -616,17 +552,7 @@ SELECT pg_size_pretty(pg_relation_size('index_name'));
|
||||
|
||||
#### Why isn’t a query using an index?
|
||||
|
||||
The query needs to have an `ORDER BY` and `LIMIT`, and the `ORDER BY` must be the result of a distance operator, not an expression.
|
||||
|
||||
```sql
|
||||
-- index
|
||||
ORDER BY embedding <=> '[3,1,2]' LIMIT 5;
|
||||
|
||||
-- no index
|
||||
ORDER BY 1 - (embedding <=> '[3,1,2]') DESC LIMIT 5;
|
||||
```
|
||||
|
||||
You can encourage the planner to use an index for a query with:
|
||||
The cost estimation in pgvector < 0.4.3 does not always work well with the planner. You can encourage the planner to use an index for a query with:
|
||||
|
||||
```sql
|
||||
BEGIN;
|
||||
@@ -704,7 +630,7 @@ Function | Description | Added
|
||||
avg(vector) → vector | average |
|
||||
sum(vector) → vector | sum | 0.5.0
|
||||
|
||||
## Installation Notes - Linux and Mac
|
||||
## Installation Notes
|
||||
|
||||
### Postgres Location
|
||||
|
||||
@@ -746,24 +672,12 @@ If compilation fails and the output includes `warning: no such sysroot directory
|
||||
|
||||
### Portability
|
||||
|
||||
By default, pgvector compiles with `-march=native` on some platforms for best performance. However, this can lead to `Illegal instruction` errors if trying to run the compiled extension on a different machine.
|
||||
|
||||
To compile for portability, use:
|
||||
|
||||
```sh
|
||||
make OPTFLAGS=""
|
||||
```
|
||||
|
||||
## Installation Notes - Windows
|
||||
|
||||
### Missing Header
|
||||
|
||||
If compilation fails with `Cannot open include file: 'postgres.h': No such file or directory`, make sure `PGROOT` is correct.
|
||||
|
||||
### Permissions
|
||||
|
||||
If installation fails with `Access is denied`, re-run the installation instructions as an administrator.
|
||||
|
||||
## Additional Installation Methods
|
||||
|
||||
### Docker
|
||||
@@ -948,12 +862,6 @@ make installcheck REGRESS=functions # regression test
|
||||
make prove_installcheck PROVE_TESTS=test/t/001_ivfflat_wal.pl # TAP test
|
||||
```
|
||||
|
||||
To enable assertions:
|
||||
|
||||
```sh
|
||||
make clean && PG_CFLAGS="-DUSE_ASSERT_CHECKING" make && make install
|
||||
```
|
||||
|
||||
To enable benchmarking:
|
||||
|
||||
```sh
|
||||
@@ -966,6 +874,12 @@ To show memory usage:
|
||||
make clean && PG_CFLAGS="-DHNSW_MEMORY -DIVFFLAT_MEMORY" make && make install
|
||||
```
|
||||
|
||||
To enable assertions:
|
||||
|
||||
```sh
|
||||
make clean && PG_CFLAGS="-DUSE_ASSERT_CHECKING" make && make install
|
||||
```
|
||||
|
||||
To get k-means metrics:
|
||||
|
||||
```sh
|
||||
|
||||
@@ -1,7 +0,0 @@
|
||||
-- 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);
|
||||
@@ -20,16 +20,12 @@ 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
|
||||
);
|
||||
|
||||
|
||||
@@ -129,7 +129,7 @@ HnswPtrDeclare(HnswNeighborArray, HnswNeighborArrayRelptr, HnswNeighborArrayPtr)
|
||||
HnswPtrDeclare(HnswNeighborArrayPtr, HnswNeighborsRelptr, HnswNeighborsPtr);
|
||||
HnswPtrDeclare(char, DatumRelptr, DatumPtr);
|
||||
|
||||
struct HnswElementData
|
||||
typedef struct HnswElementData
|
||||
{
|
||||
HnswElementPtr next;
|
||||
ItemPointerData heaptids[HNSW_HEAPTIDS];
|
||||
@@ -144,7 +144,7 @@ struct HnswElementData
|
||||
BlockNumber neighborPage;
|
||||
DatumPtr value;
|
||||
LWLock lock;
|
||||
};
|
||||
} HnswElementData;
|
||||
|
||||
typedef HnswElementData * HnswElement;
|
||||
|
||||
@@ -155,12 +155,12 @@ typedef struct HnswCandidate
|
||||
bool closer;
|
||||
} HnswCandidate;
|
||||
|
||||
struct HnswNeighborArray
|
||||
typedef struct HnswNeighborArray
|
||||
{
|
||||
int length;
|
||||
bool closerSet;
|
||||
HnswCandidate items[FLEXIBLE_ARRAY_MEMBER];
|
||||
};
|
||||
} HnswNeighborArray;
|
||||
|
||||
typedef struct HnswPairingHeapNode
|
||||
{
|
||||
|
||||
@@ -436,7 +436,7 @@ InsertTupleInMemory(HnswBuildState * buildstate, HnswElement element)
|
||||
int m = buildstate->m;
|
||||
char *base = buildstate->hnswarea;
|
||||
|
||||
/* Wait if another process needs exclusive lock on entry lock */
|
||||
/* Wait if another process needs exclusive lock */
|
||||
LWLockAcquire(entryWaitLock, LW_EXCLUSIVE);
|
||||
LWLockRelease(entryWaitLock);
|
||||
|
||||
@@ -450,7 +450,7 @@ InsertTupleInMemory(HnswBuildState * buildstate, HnswElement element)
|
||||
/* Release shared lock */
|
||||
LWLockRelease(entryLock);
|
||||
|
||||
/* Tell other processes to wait and get exclusive lock */
|
||||
/* Get exclusive lock */
|
||||
LWLockAcquire(entryWaitLock, LW_EXCLUSIVE);
|
||||
LWLockAcquire(entryLock, LW_EXCLUSIVE);
|
||||
LWLockRelease(entryWaitLock);
|
||||
|
||||
181
src/vector.c
181
src/vector.c
@@ -4,18 +4,11 @@
|
||||
|
||||
#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"
|
||||
@@ -425,180 +418,6 @@ 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
|
||||
|
||||
@@ -24,112 +24,6 @@ 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?
|
||||
----------
|
||||
|
||||
@@ -6,26 +6,6 @@ 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]';
|
||||
|
||||
|
||||
Reference in New Issue
Block a user