FEATURE: Decoder for pgvector

README.md

@@ -276,7 +276,7 @@ To install this gem onto your local machine, run `bundle exec rake install`. To
   export MINI_SQL_MYSQL_HOST=127.0.0.1
   export MINI_SQL_MYSQL_PORT=33306
 
-  docker run --name mini-sql-postgres --rm -it -p 55432:5432 -e POSTGRES_DB=test_mini_sql -e POSTGRES_HOST_AUTH_METHOD=trust -d postgres
+  docker run --name mini-sql-postgres --rm -it -p 55432:5432 -e POSTGRES_DB=test_mini_sql -e POSTGRES_HOST_AUTH_METHOD=trust -d postgres # or ankane/pgvector for testing vector type decoder
   export MINI_SQL_PG_USER=postgres
   export MINI_SQL_PG_HOST=127.0.0.1
   export MINI_SQL_PG_PORT=55432

lib/mini_sql/postgres/connection.rb

@@ -26,6 +26,20 @@ def self.type_map(conn)
             else
               map.add_coder(MiniSql::Postgres::Coders::TimestampUtc.new(name: "timestamp", oid: 1114, format: 0))
             end
+
+            if defined? Pgvector::PG
+              vector_oid =
+                PG::BasicTypeRegistry::CoderMapsBundle
+                  .new(conn)
+                  .typenames_by_oid
+                  .find { |k, v| v == "vector" }
+                  &.first
+
+              if !vector_oid.nil?
+                map.add_coder(Pgvector::PG::TextDecoder::Vector.new(name: "vector", oid: vector_oid, format: 0))
+                map.add_coder(Pgvector::PG::BinaryDecoder::Vector.new(name: "vector", oid: vector_oid, format: 1))
+              end
+            end
             map
           end
       end

mini_sql.gemspec

@@ -49,5 +49,8 @@ Gem::Specification.new do |spec|
     spec.add_development_dependency "mysql2"
     spec.add_development_dependency "sqlite3", "~> 1.4.4"
     spec.add_development_dependency "activerecord", "~> 7.0.0"
+    if RUBY_VERSION >= "3.0"
+      spec.add_development_dependency "pgvector", "~> 0.2.1"
+    end
   end
 end

test/mini_sql/postgres/connection_test.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require "test_helper"
+require "pgvector" if RUBY_ENGINE != "jruby" && RUBY_VERSION >= "3.0"
 
 class MiniSql::Postgres::TestConnection < Minitest::Test
   def setup
@@ -48,6 +49,15 @@ def test_cidr
     assert_equal(IPAddr.new("1.2.3.0/24"), ip)
   end
 
+  def test_vector
+    skip if @connection.query("SELECT 1 FROM pg_available_extensions WHERE name = 'vector';").empty?
+
+    vector = [0.1, -0.2, 0.3]
+    @connection.exec("SET client_min_messages TO WARNING; CREATE EXTENSION IF NOT EXISTS vector;")
+    result = @connection.query_single("SELECT '[:vector]'::vector", vector: vector)
+    assert_equal(vector, result.first)
+  end
+
   def test_bool
     b = @connection.query_single("select true").first
     assert_equal(true, b)