Improved examples [skip ci]

Author: ankane

examples/cohere/example.cpp

@@ -48,11 +48,10 @@ int main() {
 
     pqxx::connection conn("dbname=pgvector_example");
 
-    pqxx::work tx(conn);
+    pqxx::nontransaction tx(conn);
     tx.exec("CREATE EXTENSION IF NOT EXISTS vector");
     tx.exec("DROP TABLE IF EXISTS documents");
     tx.exec("CREATE TABLE documents (id bigserial PRIMARY KEY, content text, embedding bit(1024))");
-    tx.commit();
 
     std::vector<std::string> input = {
         "The dog is barking",
@@ -64,7 +63,6 @@ int main() {
     for (size_t i = 0; i < input.size(); i++) {
         tx.exec("INSERT INTO documents (content, embedding) VALUES ($1, $2)", pqxx::params{input[i], embeddings[i]});
     }
-    tx.commit();
 
     std::string query = "forest";
     auto query_embedding = fetch_embeddings({query}, "search_query", api_key)[0];

examples/disco/example.cpp

@@ -66,13 +66,12 @@ int main() {
 
     pqxx::connection conn("dbname=pgvector_example");
 
-    pqxx::work tx(conn);
+    pqxx::nontransaction tx(conn);
     tx.exec("CREATE EXTENSION IF NOT EXISTS vector");
     tx.exec("DROP TABLE IF EXISTS users");
     tx.exec("DROP TABLE IF EXISTS movies");
     tx.exec("CREATE TABLE users (id integer PRIMARY KEY, factors vector(20))");
     tx.exec("CREATE TABLE movies (name text PRIMARY KEY, factors vector(20))");
-    tx.commit();
 
     auto data = load_movielens(movielens_path);
     auto recommender = Recommender<int, std::string>::fit_explicit(data, { .factors = 20 });

examples/hybrid/example.cpp

@@ -34,12 +34,11 @@ std::vector<std::vector<float>> fetch_embeddings(const std::vector<std::string>&
 int main() {
     pqxx::connection conn("dbname=pgvector_example");
 
-    pqxx::work tx(conn);
+    pqxx::nontransaction tx(conn);
     tx.exec("CREATE EXTENSION IF NOT EXISTS vector");
     tx.exec("DROP TABLE IF EXISTS documents");
     tx.exec("CREATE TABLE documents (id bigserial PRIMARY KEY, content text, embedding vector(768))");
     tx.exec("CREATE INDEX ON documents USING GIN (to_tsvector('english', content))");
-    tx.commit();
 
     std::vector<std::string> input = {
         "The dog is barking",
@@ -51,7 +50,6 @@ int main() {
     for (size_t i = 0; i < input.size(); i++) {
         tx.exec("INSERT INTO documents (content, embedding) VALUES ($1, $2)", pqxx::params{input[i], pgvector::Vector(embeddings[i])});
     }
-    tx.commit();
 
     std::string sql = R"(
     WITH semantic_search AS (

examples/openai/example.cpp

@@ -40,11 +40,10 @@ int main() {
 
     pqxx::connection conn("dbname=pgvector_example");
 
-    pqxx::work tx(conn);
+    pqxx::nontransaction tx(conn);
     tx.exec("CREATE EXTENSION IF NOT EXISTS vector");
     tx.exec("DROP TABLE IF EXISTS documents");
     tx.exec("CREATE TABLE documents (id bigserial PRIMARY KEY, content text, embedding vector(1536))");
-    tx.commit();
 
     std::vector<std::string> input = {
         "The dog is barking",
@@ -56,7 +55,6 @@ int main() {
     for (size_t i = 0; i < input.size(); i++) {
         tx.exec("INSERT INTO documents (content, embedding) VALUES ($1, $2)", pqxx::params{input[i], pgvector::Vector(embeddings[i])});
     }
-    tx.commit();
 
     int document_id = 1;
     pqxx::result result = tx.exec("SELECT content FROM documents WHERE id != $1 ORDER BY embedding <=> (SELECT embedding FROM documents WHERE id = $1) LIMIT 5", pqxx::params{document_id});

examples/rdkit/example.cpp

@@ -17,18 +17,16 @@ std::string generate_fingerprint(const std::string& molecule) {
 int main() {
     pqxx::connection conn("dbname=pgvector_example");
 
-    pqxx::work tx(conn);
+    pqxx::nontransaction tx(conn);
     tx.exec("CREATE EXTENSION IF NOT EXISTS vector");
     tx.exec("DROP TABLE IF EXISTS molecules");
     tx.exec("CREATE TABLE molecules (id text PRIMARY KEY, fingerprint bit(2048))");
-    tx.commit();
 
     std::vector<std::string> molecules = {"Cc1ccccc1", "Cc1ncccc1", "c1ccccn1"};
     for (auto& molecule : molecules) {
         auto fingerprint = generate_fingerprint(molecule);
         tx.exec("INSERT INTO molecules (id, fingerprint) VALUES ($1, $2)", pqxx::params{molecule, fingerprint});
     }
-    tx.commit();
 
     std::string query_molecule = "c1ccco1";
     auto query_fingerprint = generate_fingerprint(query_molecule);

examples/sparse/example.cpp

@@ -44,11 +44,10 @@ std::vector<pgvector::SparseVector> fetch_embeddings(const std::vector<std::stri
 int main() {
     pqxx::connection conn("dbname=pgvector_example");
 
-    pqxx::work tx(conn);
+    pqxx::nontransaction tx(conn);
     tx.exec("CREATE EXTENSION IF NOT EXISTS vector");
     tx.exec("DROP TABLE IF EXISTS documents");
     tx.exec("CREATE TABLE documents (id bigserial PRIMARY KEY, content text, embedding sparsevec(30522))");
-    tx.commit();
 
     std::vector<std::string> input = {
         "The dog is barking",
@@ -60,7 +59,6 @@ int main() {
     for (size_t i = 0; i < input.size(); i++) {
         tx.exec("INSERT INTO documents (content, embedding) VALUES ($1, $2)", pqxx::params{input[i], embeddings[i]});
     }
-    tx.commit();
 
     std::string query = "forest";
     auto query_embedding = fetch_embeddings({query})[0];