GitHub - pgvector/pgvector-pascal: pgvector examples for Pascal

pgvector examples for Pascal

Supports SQLDB

Getting Started

Follow the instructions for your database library:

SQLDB

SQLDB

Enable the extension

Query.SQL.Text := 'CREATE EXTENSION IF NOT EXISTS vector';
Query.ExecSQL;

Create a table

Query.SQL.Text := 'CREATE TABLE items (id bigserial PRIMARY KEY, embedding vector(3))';
Query.ExecSQL;

Insert vectors

Query.SQL.Text := 'INSERT INTO items (embedding) VALUES ((:embedding1)::vector), ((:embedding2)::vector)';
Query.Params.ParamByName('embedding1').AsString := '[1,2,3]';
Query.Params.ParamByName('embedding2').AsString := '[4,5,6]';
Query.ExecSQL;

Get the nearest neighbors

Query.SQL.Text := 'SELECT * FROM items ORDER BY embedding <-> (:embedding)::vector LIMIT 5';
Query.Params.ParamByName('embedding').AsString := '[3,1,2]';
Query.Open;
while not Query.EOF do
begin
  writeln(Query.FieldByName('id').AsString);
  Query.Next;
end;
Query.Close;

Add an approximate index

Query.SQL.Text := 'CREATE INDEX ON items USING hnsw (embedding vector_l2_ops)';
// or
Query.SQL.Text := 'CREATE INDEX ON items USING ivfflat (embedding vector_l2_ops) WITH (lists = 100)';
Query.ExecSQL;

Use vector_ip_ops for inner product and vector_cosine_ops for cosine distance

See a full example

Contributing

Everyone is encouraged to help improve this project. Here are a few ways you can help:

Report bugs
Fix bugs and submit pull requests
Write, clarify, or fix documentation
Suggest or add new features

To get started with development:

git clone https://github.com/pgvector/pgvector-pascal.git
cd pgvector-pascal
createdb pgvector_pascal_test
fpc example.pp
./example

Specify the path to libpq if needed:

ln -s /opt/homebrew/opt/libpq/lib/libpq.dylib libpq.dylib