From 28da1261c803cfb62caf89e0885bbbe438fa0263 Mon Sep 17 00:00:00 2001
From: Marco Bubke <marco.bubke@qt.io>
Date: Thu, 29 Mar 2018 18:33:59 +0200
Subject: [PATCH] Sqlite: Use compiled statements for transactions

So we don't recompile them again and again.

Change-Id: I54c95e9d81df86f4944b9e3d45a7277f93f37312
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>
---
 src/libs/sqlite/sqlitedatabase.cpp          | 55 +++++++++++++++++++--
 src/libs/sqlite/sqlitedatabase.h            | 46 ++++++-----------
 tests/unit/unittest/sqlitedatabase-test.cpp | 35 +++++++++++++
 3 files changed, 101 insertions(+), 35 deletions(-)

diff --git a/src/libs/sqlite/sqlitedatabase.cpp b/src/libs/sqlite/sqlitedatabase.cpp
index 6fb57911396..0da9acfe314 100644
--- a/src/libs/sqlite/sqlitedatabase.cpp
+++ b/src/libs/sqlite/sqlitedatabase.cpp
@@ -27,6 +27,7 @@
 
 #include "sqlitetable.h"
 #include "sqlitetransaction.h"
+#include "sqlitereadwritestatement.h"
 
 #include <chrono>
 
@@ -54,11 +55,14 @@ Database::Database(Utils::PathString &&databaseFilePath,
     open(std::move(databaseFilePath));
 }
 
+Database::~Database() = default;
+
 void Database::open()
 {
     m_databaseBackend.open(m_databaseFilePath, m_openMode);
     m_databaseBackend.setJournalMode(m_journalMode);
     m_databaseBackend.setBusyTimeout(m_busyTimeout);
+    registerTransactionStatements();
     initializeTables();
     m_isOpen = true;
 }
@@ -129,12 +133,55 @@ void Database::execute(Utils::SmallStringView sqlStatement)
 
 void Database::initializeTables()
 {
-    ImmediateTransaction transaction(*this);
+    try {
+        ImmediateTransaction transaction(*this);
 
-    for (Table &table : m_sqliteTables)
-        table.initialize(*this);
+        for (Table &table : m_sqliteTables)
+            table.initialize(*this);
 
-    transaction.commit();
+        transaction.commit();
+    } catch (const StatementIsBusy &) {
+        initializeTables();
+    }
+}
+
+void Database::registerTransactionStatements()
+{
+    m_deferredBeginStatement = std::make_unique<ReadWriteStatement>("BEGIN", *this);
+    m_immediateBeginStatement = std::make_unique<ReadWriteStatement>("BEGIN IMMEDIATE", *this);
+    m_exclusiveBeginStatement = std::make_unique<ReadWriteStatement>("BEGIN EXCLUSIVE", *this);
+    m_commitBeginStatement = std::make_unique<ReadWriteStatement>("COMMIT", *this);
+    m_rollbackBeginStatement = std::make_unique<ReadWriteStatement>("ROLLBACK", *this);
+}
+
+void Database::deferredBegin()
+{
+    m_databaseMutex.lock();
+    m_deferredBeginStatement->execute();
+}
+
+void Database::immediateBegin()
+{
+    m_databaseMutex.lock();
+    m_immediateBeginStatement->execute();
+}
+
+void Database::exclusiveBegin()
+{
+    m_databaseMutex.lock();
+    m_exclusiveBeginStatement->execute();
+}
+
+void Database::commit()
+{
+    m_commitBeginStatement->execute();
+    m_databaseMutex.unlock();
+}
+
+void Database::rollback()
+{
+    m_rollbackBeginStatement->execute();
+    m_databaseMutex.unlock();
 }
 
 DatabaseBackend &Database::backend()
diff --git a/src/libs/sqlite/sqlitedatabase.h b/src/libs/sqlite/sqlitedatabase.h
index 83c11860ca6..c1a82b389d7 100644
--- a/src/libs/sqlite/sqlitedatabase.h
+++ b/src/libs/sqlite/sqlitedatabase.h
@@ -40,6 +40,7 @@ namespace Sqlite {
 
 class ReadStatement;
 class WriteStatement;
+class ReadWriteStatement;
 
 class SQLITE_EXPORT Database final : public TransactionInterface
 {
@@ -54,10 +55,11 @@ public:
 
     Database();
     Database(Utils::PathString &&databaseFilePath,
-             JournalMode journalMode=JournalMode::Wal);
+             JournalMode journalMode=JournalMode::Delete);
     Database(Utils::PathString &&databaseFilePath,
              std::chrono::milliseconds busyTimeout = {},
-             JournalMode journalMode=JournalMode::Wal);
+             JournalMode journalMode=JournalMode::Delete);
+    ~Database();
 
     Database(const Database &) = delete;
     Database &operator=(const Database &) = delete;
@@ -104,44 +106,26 @@ public:
         return m_databaseBackend.totalChangesCount();
     }
 
-    void deferredBegin()
-    {
-        m_databaseMutex.lock();
-        execute("BEGIN");
-    }
-
-    void immediateBegin()
-    {
-        m_databaseMutex.lock();
-        execute("BEGIN IMMEDIATE");
-    }
-
-    void exclusiveBegin()
-    {
-        m_databaseMutex.lock();
-        execute("BEGIN EXCLUSIVE");
-    }
-
-    void commit()
-    {
-        execute("COMMIT");
-        m_databaseMutex.unlock();
-    }
-
-    void rollback()
-    {
-        execute("ROLLBACK");
-        m_databaseMutex.unlock();
-    }
+    void deferredBegin();
+    void immediateBegin();
+    void exclusiveBegin();
+    void commit();
+    void rollback();
 
 private:
     void initializeTables();
+    void registerTransactionStatements();
     std::mutex &databaseMutex() { return m_databaseMutex; }
 
 private:
     Utils::PathString m_databaseFilePath;
     DatabaseBackend m_databaseBackend;
     std::vector<Table> m_sqliteTables;
+    std::unique_ptr<ReadWriteStatement> m_deferredBeginStatement;
+    std::unique_ptr<ReadWriteStatement> m_immediateBeginStatement;
+    std::unique_ptr<ReadWriteStatement> m_exclusiveBeginStatement;
+    std::unique_ptr<ReadWriteStatement> m_commitBeginStatement;
+    std::unique_ptr<ReadWriteStatement> m_rollbackBeginStatement;
     std::mutex m_databaseMutex;
     std::chrono::milliseconds m_busyTimeout;
     JournalMode m_journalMode = JournalMode::Wal;
diff --git a/tests/unit/unittest/sqlitedatabase-test.cpp b/tests/unit/unittest/sqlitedatabase-test.cpp
index 73f3a427242..ca389f58fb4 100644
--- a/tests/unit/unittest/sqlitedatabase-test.cpp
+++ b/tests/unit/unittest/sqlitedatabase-test.cpp
@@ -140,6 +140,41 @@ TEST_F(SqliteDatabase, LastRowId)
     ASSERT_THAT(database.lastInsertedRowId(), 42);
 }
 
+TEST_F(SqliteDatabase, DeferredBegin)
+{
+    ASSERT_ANY_THROW(database.deferredBegin());
+
+    database.commit();
+}
+
+TEST_F(SqliteDatabase, ImmediateBegin)
+{
+    ASSERT_ANY_THROW(database.immediateBegin());
+
+    database.commit();
+}
+
+TEST_F(SqliteDatabase, ExclusiveBegin)
+{
+    ASSERT_ANY_THROW(database.exclusiveBegin());
+
+    database.commit();
+}
+
+TEST_F(SqliteDatabase, Commit)
+{
+    database.deferredBegin();
+
+    ASSERT_ANY_THROW(database.commit());
+}
+
+TEST_F(SqliteDatabase, Rollback)
+{
+    database.deferredBegin();
+
+    ASSERT_ANY_THROW(database.rollback());
+}
+
 void SqliteDatabase::SetUp()
 {
     database.setJournalMode(JournalMode::Memory);