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Updated readme [skip ci]

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Andrew Kane
2023-04-02 10:24:21 -07:00
parent 36e73d2818
commit 58f0c922d2
1 changed files with 4 additions and 4 deletions
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README.md
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@@ -103,7 +103,7 @@ Get the nearest neighbors to a row
SELECT * FROM items WHERE id != 1 ORDER BY embedding <-> (SELECT embedding FROM items WHERE id = 1) LIMIT 5;
```
Use a `WHERE` clause to get rows within a certain distance
Get rows within a certain distance
```sql
SELECT * FROM items WHERE embedding <-> '[3,1,2]' < 5;
@@ -113,7 +113,7 @@ Note: Combine with `ORDER BY` and `LIMIT` to use an index
#### Distances
Use a `SELECT` clause to get the distance
Get the distance
```sql
SELECT embedding <-> '[3,1,2]' AS distance FROM items;
@@ -244,7 +244,7 @@ CREATE TABLE items (embedding vector(3), category_id int) PARTITION BY LIST(cate
Use `EXPLAIN ANALYZE` to debug performance.
```sql
EXPLAIN ANALYZE SELECT * FROM items ORDER BY embedding <-> '[3,1,2]' LIMIT 1;
EXPLAIN ANALYZE SELECT * FROM items ORDER BY embedding <-> '[3,1,2]' LIMIT 5;
```
### Exact Search
@@ -258,7 +258,7 @@ SET max_parallel_workers_per_gather = 4;
If vectors are normalized to length 1 (like [OpenAI embeddings](https://platform.openai.com/docs/guides/embeddings/which-distance-function-should-i-use)), use inner product for best performance.
```sql
SELECT * FROM items ORDER BY embedding <#> '[3,1,2]' LIMIT 1;
SELECT * FROM items ORDER BY embedding <#> '[3,1,2]' LIMIT 5;
```
### Approximate Search