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Sources/StructuredQueriesCore/Operators.swift

@@ -730,20 +730,6 @@ extension QueryExpression where QueryValue == String {
     LikeOperator(string: self, pattern: pattern, escape: escape)
   }
 
-  /// A predicate expression from this string expression matched against another _via_ the `MATCH`
-  /// operator.
-  ///
-  /// ```swift
-  /// Reminder.where { $0.title.match("get") }
-  /// // SELECT … FROM "reminders" WHERE ("reminders"."title" MATCH 'get')
-  /// ```
-  ///
-  /// - Parameter pattern: A string expression describing the `MATCH` pattern.
-  /// - Returns: A predicate expression.
-  public func match(_ pattern: QueryValue) -> some QueryExpression<Bool> {
-    BinaryOperator(lhs: self, operator: "MATCH", rhs: pattern)
-  }
-
   /// A predicate expression from this string expression matched against another _via_ the `LIKE`
   /// operator given a prefix.
   ///

Sources/StructuredQueriesCore/SQLite/FTS5.swift

@@ -0,0 +1,80 @@
+/// A virtual table using the FTS5 extension.
+///
+/// Apply this protocol to a `@Table` declaration to introduce FTS5 helpers.
+public protocol FTS5: Table {}
+extension TableDefinition where QueryValue: FTS5 {
+  @available(*, deprecated, message: "Virtual tables are not 'rowid' tables")
+  public var rowid: some QueryExpression<Int> {
+    SQLQueryExpression(
+      """
+      \(QueryValue.self)."rowid"
+      """
+    )
+  }
+
+  /// An expression representing the search result's rank.
+  public var rank: some QueryExpression<Double?> {
+    SQLQueryExpression(
+      """
+      \(QueryValue.self)."rank"
+      """
+    )
+  }
+
+  /// A predicate expression from this table matched against another _via_ the `MATCH` operator.
+  ///
+  /// ```swift
+  /// ReminderText.where { $0.match("get") }
+  /// // SELECT … FROM "reminderTexts" WHERE ("reminderTexts" MATCH 'get')
+  /// ```
+  ///
+  /// - Parameter pattern: A string expression describing the `MATCH` pattern.
+  /// - Returns: A predicate expression.
+  public func match(_ pattern: some QueryExpression<String>) -> some QueryExpression<Bool> {
+    SQLQueryExpression(
+      """
+      (\(QueryValue.self) MATCH \(pattern))
+      """
+    )
+  }
+}
+
+extension TableColumnExpression where Root: FTS5 {
+  /// A string expression highlighting matches in this column using the given delimiters.
+  ///
+  /// - Parameters:
+  ///   - open: An opening delimiter denoting the beginning of a match, _e.g._ `"<b>"`.
+  ///   - close: A closing delimiter denoting the end of a match, _e.g._, `"</b>"`.
+  /// - Returns: A string expression highlighting matches in this column.
+  public func highlight(
+    _ open: String,
+    _ close: String
+  ) -> some QueryExpression<String> {
+    SQLQueryExpression(
+      """
+      highlight(\
+      \(Root.self), \
+      (\
+      SELECT "cid" FROM pragma_table_info(\(quote: Root.tableName, delimiter: .text)) \
+      WHERE "name" = \(quote: name, delimiter: .text)\
+      ),
+      \(quote: open, delimiter: .text), \
+      \(quote: close, delimiter: .text)\
+      )
+      """
+    )
+  }
+
+  /// A predicate expression from this column matched against another _via_ the `MATCH` operator.
+  ///
+  /// ```swift
+  /// ReminderText.where { $0.title.match("get") }
+  /// // SELECT … FROM "reminderTexts" WHERE ("reminderTexts"."title" MATCH 'get')
+  /// ```
+  ///
+  /// - Parameter pattern: A string expression describing the `MATCH` pattern.
+  /// - Returns: A predicate expression.
+  public func match(_ pattern: some QueryExpression<String>) -> some QueryExpression<Bool> {
+    BinaryOperator(lhs: self, operator: "MATCH", rhs: pattern)
+  }
+}

Tests/StructuredQueriesTests/FTSTests.swift

@@ -0,0 +1,55 @@
+import Foundation
+import InlineSnapshotTesting
+import StructuredQueries
+import StructuredQueriesTestSupport
+import Testing
+
+extension SnapshotTests {
+  @Suite struct FTSTests {
+    @Test func basics() {
+      assertQuery(
+        ReminderText
+          .where { $0.match("take OR apple") }
+          .order(by: \.rank)
+          .select { ($0.title.highlight("**", "**"), $0.notes.highlight("**", "**")) }
+      ) {
+        """
+        SELECT highlight("reminderTexts", (SELECT "cid" FROM pragma_table_info('reminderTexts') WHERE "name" = 'title'),
+        '**', '**'), highlight("reminderTexts", (SELECT "cid" FROM pragma_table_info('reminderTexts') WHERE "name" = 'notes'),
+        '**', '**')
+        FROM "reminderTexts"
+        WHERE ("reminderTexts" MATCH 'take OR apple')
+        ORDER BY "reminderTexts"."rank"
+        """
+      } results: {
+        """
+        ┌──────────────────────┬──────────────────────────┐
+        │ "Groceries"          │ "Milk, Eggs, **Apple**s" │
+        │ "**Take** out trash" │ ""                       │
+        │ "**Take** a walk"    │ ""                       │
+        └──────────────────────┴──────────────────────────┘
+        """
+      }
+    }
+
+    @Test func unranked() {
+      assertQuery(
+        ReminderText
+          .select { ($0.listTitle, $0.rank) }
+          .limit(1)
+      ) {
+        """
+        SELECT "reminderTexts"."listTitle", "reminderTexts"."rank"
+        FROM "reminderTexts"
+        LIMIT 1
+        """
+      } results: {
+        """
+        ┌────────────┬─────┐
+        │ "Personal" │ nil │
+        └────────────┴─────┘
+        """
+      }
+    }
+  }
+}

Tests/StructuredQueriesTests/Support/Schema.swift

@@ -73,10 +73,21 @@ struct ReminderTag: Equatable {
   var title = ""
 }
 
+@Table
+struct ReminderText: FTS5 {
+  let reminderID: Reminder.ID
+  let title: String
+  let notes: String
+  let listID: RemindersList.ID
+  let listTitle: String
+  let tags: String
+}
+
 extension Database {
   static func `default`() throws -> Database {
     let db = try Database()
     try db.migrate()
+    try db.installTriggers()
     try db.seedDatabase()
     return db
   }
@@ -152,6 +163,101 @@ extension Database {
       )
       """
     )
+    try execute(
+      """
+      CREATE VIRTUAL TABLE "reminderTexts" USING fts5(
+        "reminderID" UNINDEXED,
+        "title",
+        "notes",
+        "listID" UNINDEXED,
+        "listTitle",
+        "tags",
+        tokenize = 'trigram'
+      )
+      """
+    )
+  }
+
+  func installTriggers() throws {
+    try execute(
+      Reminder.createTemporaryTrigger(
+        after: .insert { new in
+          ReminderText.insert {
+            ($0.reminderID, $0.title, $0.notes, $0.listID, $0.listTitle, $0.tags)
+          } select: {
+            Reminder
+              .find(new.id)
+              .join(RemindersList.all) { $0.remindersListID.eq($1.id) }
+              .select { ($0.id, $0.title, $0.notes, $1.id, $1.title, "") }
+          }
+        }
+      )
+    )
+    try execute(
+      Reminder.createTemporaryTrigger(
+        after: .update {
+          ($0.title, $0.notes, $0.remindersListID)
+        } forEachRow: { _, new in
+          ReminderText
+            .where { $0.reminderID.eq(new.id) }
+            .update {
+              $0.title = new.title
+              $0.notes = new.notes
+              $0.listID = new.remindersListID
+            }
+        }
+      )
+    )
+    try execute(
+      Reminder.createTemporaryTrigger(
+        after: .delete { old in
+          ReminderText
+            .where { $0.reminderID.eq(old.id) }
+            .delete()
+        }
+      )
+    )
+    try execute(
+      RemindersList.createTemporaryTrigger(
+        after: .update {
+          $0.title
+        } forEachRow: { _, new in
+          ReminderText
+            .where { $0.listID.eq(new.id) }
+            .update { $0.listTitle = new.title }
+        }
+      )
+    )
+    try execute(
+      ReminderTag.createTemporaryTrigger(
+        after: .insert { new in
+          ReminderText
+            .where { $0.reminderID.eq(new.reminderID) }
+            .update {
+              $0.tags =
+                ReminderTag
+                .where { $0.reminderID.eq(new.reminderID) }
+                .join(Tag.all) { $0.tagID.eq($1.id) }
+                .select { $1.title.groupConcat(" ") ?? "" }
+            }
+        }
+      )
+    )
+    try execute(
+      ReminderTag.createTemporaryTrigger(
+        after: .delete { old in
+          ReminderText
+            .where { $0.reminderID.eq(old.reminderID) }
+            .update {
+              $0.tags =
+                ReminderTag
+                .where { $0.reminderID.eq(old.reminderID) }
+                .join(Tag.all) { $0.tagID.eq($1.id) }
+                .select { $1.title.groupConcat(" ") ?? "" }
+            }
+        }
+      )
+    )
   }
 
   func seedDatabase() throws {