如何使用libpqxx获取postgres sqlerrorcode?

时间:2019-05-21 07:58:09

标签: c++ libpqxx

我想知道如何在插入等之后获取postgres sql错误代码。?

1 个答案:

答案 0 :(得分:0)

以下是文档中的代码段:

try
{
  // ...
}
catch (const pqxx::pqxx_exception &e)
{
  std::cerr << e.base().what() << std::endl;
  const pqxx::sql_error *s=dynamic_cast<const pqxx::sql_error*>(&e.base());
  if (s) std::cerr << "Query was: " << s->query() << std::endl;
}

一旦遇到sql_error,您可以从中检索sql状态:

std::cerr  << "SQL STATE: " << s->sqlstate() << std::endl;

因此更改上面的代码段:

pqxx::connection dbConn("dbname=tester user=foo");
pqxx::result r;
try
{
  pqxx::work transx(dbConn);
  std::string query ("SELECT name FROM compamy");
  r = transx.exec(query);
  transx.commit();  // Not necessary for a SELECT, but good practice
}
catch (const pqxx::pqxx_exception &e)
{
  std::cerr << e.base().what() << std::endl;
  const pqxx::sql_error *s=dynamic_cast<const pqxx::sql_error*>(&e.base());
  if (s) {
    std::cerr << "SQL Error code: " << s->sqlstate() << std::endl;
  }
}

鉴于表名是company,而不是compamy,将获得以下输出:

SQL Error code: 42P01

Postgresql error codes表中查找该代码:

42P01   undefined_table