search service implementation

src/basic_memory/models/knowledge.py

@@ -25,6 +25,7 @@ class Entity(Base):
     __tablename__ = "entity"
     __table_args__ = (
         UniqueConstraint("entity_type", "name", name="uix_entity_type_name"),
+        UniqueConstraint("path_id", name="uix_entity_path_id"),  # Make path_id unique
         Index("ix_entity_type", "entity_type"),
         Index("ix_entity_doc_id", "doc_id"),
         Index("ix_entity_created_at", "created_at"),  # For timeline queries
@@ -35,8 +36,7 @@ class Entity(Base):
     id: Mapped[int] = mapped_column(Integer, primary_key=True)
     name: Mapped[str] = mapped_column(String)
     entity_type: Mapped[str] = mapped_column(String)
-    # Normalized path for URIs
-    # (entity_type, path_id) are unique
+    # Normalized path for URIs - must be unique
     path_id: Mapped[str] = mapped_column(String, index=True)
     # Actual filesystem relative path
     file_path: Mapped[str] = mapped_column(String, unique=True, index=True)
@@ -157,4 +157,4 @@ class Relation(Base):
     to_entity = relationship("Entity", foreign_keys=[to_id], back_populates="incoming_relations")
 
     def __repr__(self) -> str:
-        return f"Relation(id={self.id}, from_id={self.from_id}, to_id={self.to_id}, type='{self.relation_type}')"
+        return f"Relation(id={self.id}, from_id={self.from_id}, to_id={self.to_id}, type='{self.relation_type}')"

src/basic_memory/models/search.py

@@ -0,0 +1,15 @@
+"""Search models and tables."""
+
+from sqlalchemy import DDL
+
+# Define FTS5 virtual table creation
+CREATE_SEARCH_INDEX = DDL("""
+CREATE VIRTUAL TABLE IF NOT EXISTS search_index USING fts5(
+    content,           -- Searchable text content
+    path_id UNINDEXED, -- Link to entity/document (must be unique)
+    file_path UNINDEXED, -- Filesystem path
+    type UNINDEXED,    -- 'entity' or 'document'
+    metadata UNINDEXED, -- JSON with timestamps, types, etc.
+    tokenize='porter unicode61' -- Enable stemming + unicode
+);
+""")