text: /**
   * @file    Database.cpp
   * @ingroup SQLiteCpp
   * @brief   Management of a SQLite Database Connection.
   *
   * Copyright (c) 2012-2013 Sebastien Rombauts (sebastien.rombauts@gmail.com)
   *
   * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
   * or copy at http://opensource.org/licenses/MIT)
   */
  #include <SQLiteCpp/Database.h>
  
  #include <SQLiteCpp/Statement.h>
  #include <SQLiteCpp/Assertion.h>
  #include <SQLiteCpp/Exception.h>
  
  #include <string>
  #include <sstream>
  
  #ifndef SQLITE_DETERMINISTIC
  #define SQLITE_DETERMINISTIC 0x800
  #endif // SQLITE_DETERMINISTIC
  
  
  namespace SQLite
  {
  
  
  // Open the provided database UTF-8 filename with SQLITE_OPEN_xxx provided flags.
  Database::Database(const char* apFilename, const int aFlags /*= SQLITE_OPEN_READONLY*/, const char* apVfs /*= NULL*/) :
      mpSQLite(NULL),
      mFilename(apFilename)
  {
      int ret = sqlite3_open_v2(apFilename, &mpSQLite, aFlags, apVfs);
      if (SQLITE_OK != ret)
      {
          std::ostringstream strm;
          strm << sqlite3_errmsg(mpSQLite) << " (" << ret << ")";
  
          sqlite3_close(mpSQLite); // close is required even in case of error on opening
  
          throw SQLite::Exception(strm.str());
      }
  }
  
  // Open the provided database UTF-8 filename with SQLITE_OPEN_xxx provided flags.
  Database::Database(const std::string& aFilename, const int aFlags /*= SQLITE_OPEN_READONLY*/, const std::string& aVfs) :
      mpSQLite(NULL),
      mFilename(aFilename)
  {
      int ret = sqlite3_open_v2(aFilename.c_str(), &mpSQLite, aFlags, aVfs.empty() ? NULL : aVfs.c_str());
      if (SQLITE_OK != ret)
      {
          std::ostringstream strm;
          strm << sqlite3_errmsg(mpSQLite) << " (" << ret << ")";
  
          sqlite3_close(mpSQLite); // close is required even in case of error on opening
          throw SQLite::Exception(strm.str());
      }
  }
  
  // Close the SQLite database connection.
  Database::~Database() noexcept // nothrow
  {
      int ret = sqlite3_close(mpSQLite);
      // Never throw an exception in a destructor
      SQLITECPP_ASSERT(SQLITE_OK == ret, sqlite3_errmsg(mpSQLite));  // See SQLITECPP_ENABLE_ASSERT_HANDLER
  }
  
  // Shortcut to execute one or multiple SQL statements without results (UPDATE, INSERT, ALTER, COMMIT, CREATE...).
  int Database::exec(const char* apQueries)
  {
      int ret = sqlite3_exec(mpSQLite, apQueries, NULL, NULL, NULL);
      check(ret);
  
      // Return the number of rows modified by those SQL statements (INSERT, UPDATE or DELETE only)
      return sqlite3_changes(mpSQLite);
  }
  
  // Shortcut to execute a one step query and fetch the first column of the result.
  // WARNING: Be very careful with this dangerous method: you have to
  // make a COPY OF THE result, else it will be destroy before the next line
  // (when the underlying temporary Statement and Column objects are destroyed)
  // this is an issue only for pointer type result (ie. char* and blob)
  // (use the Column copy-constructor)
  Column Database::execAndGet(const char* apQuery)
  {
      Statement query(*this, apQuery);
      (void)query.executeStep(); // Can return false if no result, which will throw next line in getColumn()
      return query.getColumn(0);
  }
  
  // Shortcut to test if a table exists.
  bool Database::tableExists(const char* apTableName)
  {
      Statement query(*this, "SELECT count(*) FROM sqlite_master WHERE type='table' AND name=?");
      query.bind(1, apTableName);
      (void)query.executeStep(); // Cannot return false, as the above query always return a result
      int Nb = query.getColumn(0);
      return (1 == Nb);
  }
  
  // Check if aRet equal SQLITE_OK, else throw a SQLite::Exception with the SQLite error message
  void Database::check(const int aRet) const
  {
      if (SQLITE_OK != aRet)
      {
          std::ostringstream strm;
  
          strm << sqlite3_errmsg(mpSQLite) << " (" << aRet << ")";
  
          throw SQLite::Exception(strm.str());
      }
  }
  
  // Attach a custom function to your sqlite database. Assumes UTF8 text representation.
  // Parameter details can be found here: http://www.sqlite.org/c3ref/create_function.html
  void Database::createFunction(const char*   apFuncName,
                                int           aNbArg,
                                bool          abDeterministic,
                                void*         apApp,
                                void        (*apFunc)(sqlite3_context *, int, sqlite3_value **),
                                void        (*apStep)(sqlite3_context *, int, sqlite3_value **),
                                void        (*apFinal)(sqlite3_context *),   // NOLINT(readability/casting)
                                void        (*apDestroy)(void *))
  {
      int TextRep = SQLITE_UTF8;
      // optimization if deterministic function (e.g. of nondeterministic function random())
      if (abDeterministic) {
          TextRep = TextRep|SQLITE_DETERMINISTIC;
      }
      int ret = sqlite3_create_function_v2(mpSQLite, apFuncName, aNbArg, TextRep,
                                           apApp, apFunc, apStep, apFinal, apDestroy);
  
      check(ret);
  }
  
  
  }  // namespace SQLite
  