rewriten migration

migrations/0003_create_sentence_embeddings_table.up.sql

@@ -1,16 +1,16 @@
 -- +goose Up
-CREATE EXTENSION IF NOT EXISTS vector;
-
+-- Create sentence_embeddings table using standard Postgres types (no vector extension)
 CREATE TABLE sentence_embeddings (
     id SERIAL PRIMARY KEY,
     visit_id INTEGER NOT NULL,
     sentence TEXT NOT NULL,
     translated TEXT,
-    embeddings VECTOR(1536) NOT NULL,
+    embeddings FLOAT[] NOT NULL, -- Using standard float array instead of vector
     created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
 );
 
+-- Create unique index for efficient lookups and preventing duplicates
+CREATE UNIQUE INDEX idx_sentence_embeddings_visit_sentence ON sentence_embeddings (visit_id, sentence);
+
 -- +goose Down
 DROP TABLE IF EXISTS sentence_embeddings;
-DROP EXTENSION IF EXISTS vector;
-

migrations/0004_alter_sentence_embeddings_visit_id_type.up.sql

@@ -1,8 +1,8 @@
 -- +goose Up
+-- Altering visit_id type, keeping compatibility with standard Postgres types
 ALTER TABLE sentence_embeddings
-    ALTER COLUMN visit_id TYPE TEXT USING visit_id::text;
+    ALTER COLUMN visit_id TYPE TEXT;
 
 -- +goose Down
 ALTER TABLE sentence_embeddings
-    ALTER COLUMN visit_id TYPE INTEGER USING visit_id::integer;
-
+    ALTER COLUMN visit_id TYPE INTEGER USING (visit_id::integer);

migrations/0005_add_unique_idx_sentence_embeddings.up.sql

@@ -1,6 +1,6 @@
 -- +goose Up
-CREATE UNIQUE INDEX IF NOT EXISTS ux_sentence_embeddings_visit_sentence
-    ON sentence_embeddings(visit_id, sentence);
+-- The unique index was already created in migration 0003 when we switched to standard Postgres types
+-- This migration is kept for consistency in migration sequence but doesn't perform any action
 
 -- +goose Down
-DROP INDEX IF EXISTS ux_sentence_embeddings_visit_sentence;
+-- No action needed for rollback

migrations/0006_alter_sentence_embeddings_dim_384.up.sql

@@ -1,14 +1,6 @@
 -- +goose Up
--- WARNING: This alters the embeddings vector dimension from 1536 to 384.
--- Ensure you are switching to a 384-dim embedding model (e.g., all-minilm).
--- If existing rows have 1536-d vectors this command will fail; you may need to
--- TRUNCATE TABLE sentence_embeddings first (after backing up) before applying.
-ALTER TABLE sentence_embeddings
-    ALTER COLUMN embeddings TYPE vector(384);
+-- Update schema to support 384-dimensional embeddings using standard Postgres types
+-- No need to modify column type as we're now using a flexible FLOAT[] array
 
 -- +goose Down
--- Revert to 1536 dimensions (for models like OpenAI text-embedding-3-large).
--- Will fail if existing rows are 384-d.
-ALTER TABLE sentence_embeddings
-    ALTER COLUMN embeddings TYPE vector(1536);
-
+-- No action needed for rollback since we're using a flexible array type

migrations/0007_add_dual_embedding_columns.up.sql

@@ -1,13 +1,10 @@
 -- +goose Up
--- Add separate columns for different embedding dimensions.
--- Existing 'embeddings' column (if present) is left untouched for backward compatibility.
--- Application code will now populate embedding_384 or embedding_1536 instead.
+-- Add separate columns for different embedding dimensions using standard Postgres FLOAT[] arrays
 ALTER TABLE sentence_embeddings
-    ADD COLUMN IF NOT EXISTS embedding_384   vector(384),
-    ADD COLUMN IF NOT EXISTS embedding_1536  vector(1536);
+    ADD COLUMN IF NOT EXISTS embedding_384 FLOAT[],
+    ADD COLUMN IF NOT EXISTS embedding_1536 FLOAT[];
 
 -- +goose Down
 ALTER TABLE sentence_embeddings
     DROP COLUMN IF EXISTS embedding_384,
     DROP COLUMN IF EXISTS embedding_1536;
-

migrations/0008_drop_legacy_embeddings_column.up.sql

@@ -1,11 +1,7 @@
 -- +goose Up
--- Drop the legacy single-dimension embeddings column (was NOT NULL) to allow inserts
--- that now use embedding_384 / embedding_1536. All new data goes into those columns.
+-- Drop legacy embeddings column as it's been replaced by embedding_384 and embedding_1536
 ALTER TABLE sentence_embeddings
     DROP COLUMN IF EXISTS embeddings;
 
 -- +goose Down
--- Re-create the legacy embeddings column (empty) as vector(1536) NULLABLE for rollback.
-ALTER TABLE sentence_embeddings
-    ADD COLUMN IF NOT EXISTS embeddings vector(1536);
-
+-- No restoration action needed as embedding_384 and embedding_1536 are preserved

repository.go

@@ -277,18 +277,18 @@ func (r *PGChatRepository) InsertSentenceEmbedding(ctx context.Context, visitID,
 		logrus.WithError(err).Warn("skipping sentence embedding insert")
 		return err
 	}
-	// Build vector literal
+	// Build array literal
 	var b strings.Builder
 	b.Grow(len(embedding)*8 + 2)
-	b.WriteByte('[')
+	b.WriteByte('{')
 	for i, v := range embedding {
 		if i > 0 {
 			b.WriteByte(',')
 		}
 		b.WriteString(strconv.FormatFloat(v, 'f', -1, 64))
 	}
-	b.WriteByte(']')
-	vecLiteral := b.String()
+	b.WriteByte('}')
+	arrayLiteral := b.String()
 
 	ctx, cancel := context.WithTimeout(ctx, 6*time.Second)
 	defer cancel()
@@ -296,18 +296,18 @@ func (r *PGChatRepository) InsertSentenceEmbedding(ctx context.Context, visitID,
 	var sqlStmt string
 	if l == 384 {
 		sqlStmt = `INSERT INTO sentence_embeddings (visit_id, sentence, translated, embedding_384)
-			VALUES ($1,$2,$3,$4::vector)
+			VALUES ($1,$2,$3,$4::float[])
 			ON CONFLICT (visit_id, sentence) DO UPDATE
 			SET embedding_384 = EXCLUDED.embedding_384,
 			    translated = COALESCE(sentence_embeddings.translated, EXCLUDED.translated)`
 	} else { // 1536
 		sqlStmt = `INSERT INTO sentence_embeddings (visit_id, sentence, translated, embedding_1536)
-			VALUES ($1,$2,$3,$4::vector)
+			VALUES ($1,$2,$3,$4::float[])
 			ON CONFLICT (visit_id, sentence) DO UPDATE
 			SET embedding_1536 = EXCLUDED.embedding_1536,
 			    translated = COALESCE(sentence_embeddings.translated, EXCLUDED.translated)`
 	}
-	_, err := r.pool.Exec(ctx, sqlStmt, visitID, sentence, translated, vecLiteral)
+	_, err := r.pool.Exec(ctx, sqlStmt, visitID, sentence, translated, arrayLiteral)
 	if err != nil {
 		logrus.WithError(err).Warn("failed to upsert sentence embedding (dual columns)")
 	}