Use cached statements

Sources/SQLiteData/FetchAll+Sections.swift

@@ -1556,15 +1556,15 @@ struct FetchAllSectionedStatementValueRequest<
   Key: QueryRepresentable
 >: FetchKeyRequest
 where Value.QueryOutput: Sendable, Key.QueryOutput: Hashable & Sendable {
-  let statement: SQLQueryExpression<(Value, Key)>
+  let prepared: PreparedQuery
 
   init(
     statement: Select<(), Value, ()>,
     sectionBy: _Sectioning<Key>
   ) where Value: StructuredQueriesCore.Table {
     let prefix: Select<(Value, Key), Value, ()> = sectionedColumns(of: Value.self, sectionBy)
     let sectioned: Select<(Value, Key), Value, ()> = prefix + statement
-    self.statement = SQLQueryExpression(sectioned)
+    self.prepared = PreparedQuery(sectioned.query)
   }
 
   init<From: StructuredQueriesCore.Table, each J: StructuredQueriesCore.Table>(
@@ -1575,21 +1575,21 @@ where Value.QueryOutput: Sendable, Key.QueryOutput: Hashable & Sendable {
       sectionedOrder(of: From.self, sectionBy) + statement
     let sectioned: Select<(Value, Key), From, (repeat each J)> =
       ordered + sectionedColumn(of: From.self, sectionBy)
-    self.statement = SQLQueryExpression(sectioned)
+    self.prepared = PreparedQuery(sectioned.query)
   }
 
   func fetch(_ db: Database) throws -> ResultsSectionCollection<Value.QueryOutput, Key.QueryOutput>
   {
     try ResultsSectionCollection(
-      cursor: QuerySectionedCursor<Value, Key>(db: db, query: statement.queryFragment)
+      cursor: QuerySectionedCursor<Value, Key>(db: db, prepared: prepared, cached: true)
     )
   }
 
   static func == (lhs: Self, rhs: Self) -> Bool {
-    lhs.statement.query == rhs.statement.query
+    lhs.prepared == rhs.prepared
   }
 
   func hash(into hasher: inout Hasher) {
-    hasher.combine(statement.query)
+    hasher.combine(prepared)
   }
 }

Sources/SQLiteData/FetchAll.swift

@@ -597,12 +597,15 @@ extension FetchAll: Equatable where Element: Equatable {
   }
 #endif
 
-struct FetchAllStatementValueRequest<Value: QueryRepresentable>: StatementKeyRequest {
-  let statement: SQLQueryExpression<Value>
-  init(statement: some StructuredQueriesCore.Statement<Value>) {
-    self.statement = SQLQueryExpression(statement)
+struct FetchAllStatementValueRequest<QueryValue: QueryRepresentable>: StatementKeyRequest {
+  let prepared: PreparedQuery
+  init(statement: some StructuredQueriesCore.Statement<QueryValue>) {
+    self.prepared = PreparedQuery(statement.query)
   }
-  func fetch(_ db: Database) throws -> [Value.QueryOutput] {
-    try statement.fetchAll(db)
+  func fetch(_ db: Database) throws -> [QueryValue.QueryOutput] {
+    let cursor = try QueryValueCursor<QueryValue>(db: db, prepared: prepared, cached: true)
+    var output: [QueryValue.QueryOutput] = []
+    try cursor.forEach { output.append($0) }
+    return output
   }
 }

Sources/SQLiteData/FetchOne.swift

@@ -1495,38 +1495,39 @@ extension FetchOne: Equatable where Value: Equatable {
   }
 #endif
 
-private struct FetchOneStatementValueRequest<Value: QueryRepresentable>: StatementKeyRequest {
-  let statement: SQLQueryExpression<Value>
-  init(statement: some StructuredQueriesCore.Statement<Value>) {
-    self.statement = SQLQueryExpression(statement)
+private struct FetchOneStatementValueRequest<QueryValue: QueryRepresentable>: StatementKeyRequest {
+  let prepared: PreparedQuery
+  init(statement: some StructuredQueriesCore.Statement<QueryValue>) {
+    self.prepared = PreparedQuery(statement.query)
   }
-  func fetch(_ db: Database) throws -> Value.QueryOutput {
-    guard let result = try statement.fetchOne(db)
+  func fetch(_ db: Database) throws -> QueryValue.QueryOutput {
+    guard
+      let result = try QueryValueCursor<QueryValue>(db: db, prepared: prepared, cached: true).next()
     else { throw NotFound() }
     return result
   }
 }
 
-private struct FetchOneStatementOptionalValueRequest<Value: QueryRepresentable>:
+private struct FetchOneStatementOptionalValueRequest<QueryValue: QueryRepresentable>:
   StatementKeyRequest
 {
-  let statement: SQLQueryExpression<Value>
-  init(statement: some StructuredQueriesCore.Statement<Value>) {
-    self.statement = SQLQueryExpression(statement)
+  let prepared: PreparedQuery
+  init(statement: some StructuredQueriesCore.Statement<QueryValue>) {
+    self.prepared = PreparedQuery(statement.query)
   }
-  func fetch(_ db: Database) throws -> Value.QueryOutput? {
-    try statement.fetchOne(db)
+  func fetch(_ db: Database) throws -> QueryValue.QueryOutput? {
+    try QueryValueCursor<QueryValue>(db: db, prepared: prepared, cached: true).next()
   }
 }
 
 private struct FetchOneStatementOptionalProtocolRequest<
-  Value: QueryRepresentable & StructuredQueriesCore._OptionalProtocol
->: StatementKeyRequest where Value.QueryOutput: StructuredQueriesCore._OptionalProtocol {
-  let statement: SQLQueryExpression<Value>
-  init(statement: some StructuredQueriesCore.Statement<Value>) {
-    self.statement = SQLQueryExpression(statement)
+  QueryValue: QueryRepresentable & StructuredQueriesCore._OptionalProtocol
+>: StatementKeyRequest where QueryValue.QueryOutput: StructuredQueriesCore._OptionalProtocol {
+  let prepared: PreparedQuery
+  init(statement: some StructuredQueriesCore.Statement<QueryValue>) {
+    self.prepared = PreparedQuery(statement.query)
   }
-  func fetch(_ db: Database) throws -> Value.QueryOutput {
-    try statement.fetchOne(db) ?? ._none
+  func fetch(_ db: Database) throws -> QueryValue.QueryOutput {
+    try QueryValueCursor<QueryValue>(db: db, prepared: prepared, cached: true).next() ?? ._none
   }
 }

Sources/SQLiteData/Internal/StatementKey.swift

@@ -2,15 +2,16 @@ import StructuredQueriesCore
 
 protocol StatementKeyRequest<QueryValue>: FetchKeyRequest {
   associatedtype QueryValue
-  var statement: SQLQueryExpression<QueryValue> { get }
+  var prepared: PreparedQuery { get }
 }
 
 extension StatementKeyRequest {
   static func == (lhs: Self, rhs: Self) -> Bool {
-    lhs.statement.query == rhs.statement.query
+    lhs.prepared.sql == rhs.prepared.sql && lhs.prepared.bindings == rhs.prepared.bindings
   }
 
   func hash(into hasher: inout Hasher) {
-    hasher.combine(statement.query)
+    hasher.combine(prepared.sql)
+    hasher.combine(prepared.bindings)
   }
 }

Sources/SQLiteData/StructuredQueries+GRDB/QueryCursor.swift

@@ -14,12 +14,18 @@ public class QueryCursor<Element>: DatabaseCursor {
   var decoder: SQLiteQueryDecoder
 
   @usableFromInline
-  init(db: Database, query: QueryFragment) throws {
-    (_statement, decoder) = try db.prepare(query: query)
+  init(db: Database, prepared: PreparedQuery, cached: Bool) throws {
+    (_statement, decoder) = try db.prepare(prepared, cached: cached)
+  }
+
+  @usableFromInline
+  convenience init(db: Database, query: QueryFragment, cached: Bool) throws {
+    try self.init(db: db, prepared: PreparedQuery(query), cached: cached)
   }
 
   deinit {
     sqlite3_reset(_statement.sqliteStatement)
+    sqlite3_clear_bindings(_statement.sqliteStatement)
   }
 
   public func _element(sqliteStatement _: SQLiteStatement) throws -> Element {
@@ -84,8 +90,8 @@ final class QueryValueCursor<QueryValue: QueryRepresentable>: QueryCursor<QueryV
   // NB: Required to workaround a "Legacy previews execution" bug
   //     https://github.com/pointfreeco/sqlite-data/pull/60
   @usableFromInline
-  override init(db: Database, query: QueryFragment) throws {
-    try super.init(db: db, query: query)
+  override init(db: Database, prepared: PreparedQuery, cached: Bool) throws {
+    try super.init(db: db, prepared: prepared, cached: cached)
   }
 
   @inlinable
@@ -110,8 +116,8 @@ final class QuerySectionedCursor<
   // NB: Required to workaround a "Legacy previews execution" bug
   //     https://github.com/pointfreeco/sqlite-data/pull/60
   @usableFromInline
-  override init(db: Database, query: QueryFragment) throws {
-    try super.init(db: db, query: query)
+  override init(db: Database, prepared: PreparedQuery, cached: Bool) throws {
+    try super.init(db: db, prepared: prepared, cached: cached)
   }
 
   @inlinable
@@ -139,8 +145,8 @@ final class QueryPackCursor<
   // NB: Required to workaround a "Legacy previews execution" bug
   //     https://github.com/pointfreeco/sqlite-data/pull/60
   @usableFromInline
-  override init(db: Database, query: QueryFragment) throws {
-    try super.init(db: db, query: query)
+  override init(db: Database, prepared: PreparedQuery, cached: Bool) throws {
+    try super.init(db: db, prepared: prepared, cached: cached)
   }
 
   @inlinable
@@ -164,8 +170,8 @@ final class QueryVoidCursor: QueryCursor<Void> {
   // NB: Required to workaround a "Legacy previews execution" bug
   //     https://github.com/pointfreeco/sqlite-data/pull/60
   @usableFromInline
-  override init(db: Database, query: QueryFragment) throws {
-    try super.init(db: db, query: query)
+  override init(db: Database, prepared: PreparedQuery, cached: Bool) throws {
+    try super.init(db: db, prepared: prepared, cached: cached)
   }
 
   @inlinable
@@ -175,15 +181,38 @@ final class QueryVoidCursor: QueryCursor<Void> {
   }
 }
 
-extension Database {
-  @inlinable
-  func prepare(query: QueryFragment) throws -> (GRDB.Statement, SQLiteQueryDecoder) {
+@usableFromInline
+struct PreparedQuery: Hashable, Sendable {
+  @usableFromInline
+  let sql: String
+
+  @usableFromInline
+  let bindings: [QueryBinding]
+
+  @usableFromInline
+  init(_ query: QueryFragment) {
     var (sql, bindings) = query.prepare { _ in "?" }
     if sql.isEmpty {
       sql = "SELECT 1 WHERE 0 -- Empty query generated by StructuredQueries"
     }
-    let statement = try makeStatement(sql: sql)
-    for (index, binding) in zip(Int32(1)..., bindings) {
+    self.sql = sql
+    self.bindings = bindings
+  }
+}
+
+extension Database {
+  @usableFromInline
+  func prepare(
+    _ prepared: PreparedQuery, cached: Bool
+  ) throws -> (GRDB.Statement, SQLiteQueryDecoder) {
+    let statement: GRDB.Statement
+    if cached {
+      statement = try cachedStatement(sql: prepared.sql)
+      sqlite3_reset(statement.sqliteStatement)
+    } else {
+      statement = try makeStatement(sql: prepared.sql)
+    }
+    for (index, binding) in zip(Int32(1)..., prepared.bindings) {
       try binding.bind(to: statement.sqliteStatement, at: index)
     }
     return (

Sources/SQLiteData/StructuredQueries+GRDB/Statement+GRDB.swift

@@ -18,7 +18,7 @@ extension StructuredQueriesCore.Statement {
   /// - Parameter db: A database connection.
   @inlinable
   public func execute(_ db: Database) throws where QueryValue == () {
-    try QueryVoidCursor(db: db, query: query).next()
+    try QueryVoidCursor(db: db, query: query, cached: true).next()
   }
 
   /// Returns an array of all values fetched from the database.
@@ -41,7 +41,7 @@ extension StructuredQueriesCore.Statement {
   @inlinable
   public func fetchAll(_ db: Database) throws -> [QueryValue.QueryOutput]
   where QueryValue: QueryRepresentable {
-    let cursor = try QueryValueCursor<QueryValue>(db: db, query: query)
+    let cursor = try QueryValueCursor<QueryValue>(db: db, query: query, cached: true)
     var output: [QueryValue.QueryOutput] = []
     try cursor.forEach { output.append($0) }
     return output
@@ -69,7 +69,7 @@ extension StructuredQueriesCore.Statement {
   @inlinable
   public func fetchOne(_ db: Database) throws -> QueryValue.QueryOutput?
   where QueryValue: QueryRepresentable {
-    try fetchCursor(db).next()
+    try QueryValueCursor<QueryValue>(db: db, query: query, cached: true).next()
   }
 
   /// Returns a cursor to all values fetched from the database.
@@ -92,7 +92,7 @@ extension StructuredQueriesCore.Statement {
   @inlinable
   public func fetchCursor(_ db: Database) throws -> QueryCursor<QueryValue.QueryOutput>
   where QueryValue: QueryRepresentable {
-    try QueryValueCursor<QueryValue>(db: db, query: query)
+    try QueryValueCursor<QueryValue>(db: db, query: query, cached: false)
   }
 }
 
@@ -108,7 +108,7 @@ extension StructuredQueriesCore.Statement {
     _ db: Database
   ) throws -> [(repeat (each Value).QueryOutput)]
   where QueryValue == (repeat each Value) {
-    let cursor = try fetchCursor(db)
+    let cursor = try QueryPackCursor<repeat each Value>(db: db, query: query, cached: true)
     return try Array(cursor)
   }
 
@@ -122,7 +122,7 @@ extension StructuredQueriesCore.Statement {
     _ db: Database
   ) throws -> (repeat (each Value).QueryOutput)?
   where QueryValue == (repeat each Value) {
-    let cursor = try fetchCursor(db)
+    let cursor = try QueryPackCursor<repeat each Value>(db: db, query: query, cached: true)
     return try cursor.next()
   }
 
@@ -136,7 +136,7 @@ extension StructuredQueriesCore.Statement {
     _ db: Database
   ) throws -> QueryCursor<(repeat (each Value).QueryOutput)>
   where QueryValue == (repeat each Value) {
-    try QueryPackCursor<repeat each Value>(db: db, query: query)
+    try QueryPackCursor<repeat each Value>(db: db, query: query, cached: false)
   }
 }
 
@@ -160,7 +160,7 @@ extension SelectStatement where QueryValue == (), Joins == () {
   @_documentation(visibility: private)
   @inlinable
   public func fetchAll(_ db: Database) throws -> [From.QueryOutput] {
-    let cursor = try QueryValueCursor<From>(db: db, query: query)
+    let cursor = try QueryValueCursor<From>(db: db, query: query, cached: true)
     var output: [From.QueryOutput] = []
     try cursor.forEach { output.append($0) }
     return output
@@ -173,7 +173,7 @@ extension SelectStatement where QueryValue == (), Joins == () {
   @_documentation(visibility: private)
   @inlinable
   public func fetchOne(_ db: Database) throws -> From.QueryOutput? {
-    try asSelect().limit(1).fetchCursor(db).next()
+    try QueryValueCursor<From>(db: db, query: asSelect().limit(1).query, cached: true).next()
   }
 
   /// Returns a cursor to all values fetched from the database.
@@ -183,7 +183,7 @@ extension SelectStatement where QueryValue == (), Joins == () {
   @_documentation(visibility: private)
   @inlinable
   public func fetchCursor(_ db: Database) throws -> QueryCursor<From.QueryOutput> {
-    try QueryValueCursor<From>(db: db, query: query)
+    try QueryValueCursor<From>(db: db, query: query, cached: false)
   }
 }
 
@@ -218,7 +218,7 @@ extension SelectStatement where QueryValue == () {
     _ db: Database
   ) throws -> [(From.QueryOutput, repeat (each J).QueryOutput)]
   where Joins == (repeat each J) {
-    try Array(fetchCursor(db))
+    try Array(QueryPackCursor<From, repeat each J>(db: db, query: query, cached: true))
   }
 
   /// Returns a single value fetched from the database.
@@ -231,7 +231,10 @@ extension SelectStatement where QueryValue == () {
     _ db: Database
   ) throws -> (From.QueryOutput, repeat (each J).QueryOutput)?
   where Joins == (repeat each J) {
-    try asSelect().limit(1).fetchCursor(db).next()
+    try QueryPackCursor<From, repeat each J>(
+      db: db, query: asSelect().limit(1).query, cached: true
+    )
+    .next()
   }
 
   /// Returns a cursor to all values fetched from the database.
@@ -244,6 +247,6 @@ extension SelectStatement where QueryValue == () {
     _ db: Database
   ) throws -> QueryCursor<(From.QueryOutput, repeat (each J).QueryOutput)>
   where Joins == (repeat each J) {
-    try QueryPackCursor<From, repeat each J>(db: db, query: query)
+    try QueryPackCursor<From, repeat each J>(db: db, query: query, cached: false)
   }
 }

Sources/SQLiteData/StructuredQueries+GRDB/Statement+Sections.swift

@@ -141,5 +141,7 @@ private func sectionedResults<Value: QueryRepresentable, Key: QueryRepresentable
   query: QueryFragment
 ) throws -> ResultsSectionCollection<Value.QueryOutput, Key.QueryOutput>
 where Key.QueryOutput: Hashable {
-  try ResultsSectionCollection(cursor: QuerySectionedCursor<Value, Key>(db: db, query: query))
+  try ResultsSectionCollection(
+    cursor: QuerySectionedCursor<Value, Key>(db: db, query: query, cached: true)
+  )
 }