wip

Author: stephencelis

Sources/StructuredQueriesCore/SQLite/FTS5.swift

@@ -11,40 +11,41 @@ extension TableDefinition where QueryValue: FTS5 {
   /// - Parameter rankings: A dictionary mapping columns to accuracy of a match.
   /// - Returns: A BM25 ranking function.
   public func bm25(
-    _ rankings: [PartialKeyPath<Self>: Double]
+    _ rankings: [PartialKeyPath<Self>: Double] = [:]
   ) -> some QueryExpression<Double> {
-    guard !rankings.isEmpty else { return SQLQueryExpression("0") }
     var queryFragments: [QueryFragment] = ["\(QueryValue.self)"]
-    var columnNameToRanking: QueryFragment = """
-      CASE "name"
-      """
-    for (keyPath, ranking) in rankings {
-      guard let column = self[keyPath: keyPath] as? any WritableTableColumnExpression
-      else {
-        reportIssue(
-          """
-          Key path cannot be used in 'bm25' function: \(keyPath)
+    if !rankings.isEmpty {
+      var columnNameToRanking: QueryFragment = """
+        CASE "name"
+        """
+      for (keyPath, ranking) in rankings {
+        guard let column = self[keyPath: keyPath] as? any WritableTableColumnExpression
+        else {
+          reportIssue(
+            """
+            Key path cannot be used in 'bm25' function: \(keyPath)
 
-          Must be a key path to a table column on '\(QueryValue.self)'.
+            Must be a key path to a table column on '\(QueryValue.self)'.
+            """
+          )
+          continue
+        }
+        columnNameToRanking.append(
+          """
+           WHEN \(bind: column.name) THEN \(ranking)
+          """
+        )
+      }
+      columnNameToRanking.append(" ELSE 1 END")
+      for offset in Self.writableColumns.indices {
+        queryFragments.append(
+          """
+          (SELECT \(columnNameToRanking) \
+          FROM pragma_table_info(\(quote: QueryValue.tableName, delimiter: .text)) \
+          WHERE "cid" = \(offset))
           """
         )
-        continue
       }
-      columnNameToRanking.append(
-        """
-         WHEN \(bind: column.name) THEN \(ranking)
-        """
-      )
-    }
-    columnNameToRanking.append(" ELSE 1 END")
-    for offset in Self.writableColumns.indices {
-      queryFragments.append(
-        """
-        (SELECT \(columnNameToRanking) \
-        FROM pragma_table_info(\(quote: QueryValue.tableName, delimiter: .text)) \
-        WHERE "cid" = \(offset))
-        """
-      )
     }
     return SQLQueryExpression("bm25(\(queryFragments.joined(separator: ", ")))")
   }

Tests/StructuredQueriesTests/FTSTests.swift

@@ -97,7 +97,32 @@ extension SnapshotTests {
         SELECT "reminderTexts"."reminderID", "reminderTexts"."title", "reminderTexts"."notes", "reminderTexts"."listID", "reminderTexts"."listTitle", "reminderTexts"."tags"
         FROM "reminderTexts"
         WHERE ("reminderTexts" MATCH 'Week')
-        ORDER BY bm25("reminderTexts", (SELECT CASE "name" WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 WHEN 'tags' THEN 2.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 0), (SELECT CASE "name" WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 WHEN 'tags' THEN 2.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 1), (SELECT CASE "name" WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 WHEN 'tags' THEN 2.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 2), (SELECT CASE "name" WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 WHEN 'tags' THEN 2.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 3), (SELECT CASE "name" WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 WHEN 'tags' THEN 2.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 4), (SELECT CASE "name" WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 WHEN 'tags' THEN 2.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 5))
+        ORDER BY bm25("reminderTexts", (SELECT CASE "name" WHEN 'tags' THEN 2.0 WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 0), (SELECT CASE "name" WHEN 'tags' THEN 2.0 WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 1), (SELECT CASE "name" WHEN 'tags' THEN 2.0 WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 2), (SELECT CASE "name" WHEN 'tags' THEN 2.0 WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 3), (SELECT CASE "name" WHEN 'tags' THEN 2.0 WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 4), (SELECT CASE "name" WHEN 'tags' THEN 2.0 WHEN 'title' THEN 10.0 WHEN 'notes' THEN 5.0 ELSE 1 END FROM pragma_table_info('reminderTexts') WHERE "cid" = 5))
+        """
+      } results: {
+        """
+        ┌────────────────────────────────┐
+        │ ReminderText(                  │
+        │   reminderID: 10,              │
+        │   title: "Send weekly emails", │
+        │   notes: "",                   │
+        │   listID: 3,                   │
+        │   listTitle: "Business",       │
+        │   tags: ""                     │
+        │ )                              │
+        └────────────────────────────────┘
+        """
+      }
+      assertQuery(
+        ReminderText
+          .where { $0.match("Week") }
+          .order { $0.bm25() }
+      ) {
+        """
+        SELECT "reminderTexts"."reminderID", "reminderTexts"."title", "reminderTexts"."notes", "reminderTexts"."listID", "reminderTexts"."listTitle", "reminderTexts"."tags"
+        FROM "reminderTexts"
+        WHERE ("reminderTexts" MATCH 'Week')
+        ORDER BY bm25("reminderTexts")
         """
       } results: {
         """