diff options
| -rw-r--r-- | odb/mysql/query.cxx | 43 |
1 files changed, 32 insertions, 11 deletions
diff --git a/odb/mysql/query.cxx b/odb/mysql/query.cxx index 5727e4e..e5c1705 100644 --- a/odb/mysql/query.cxx +++ b/odb/mysql/query.cxx @@ -28,6 +28,18 @@ namespace odb bind_ (q.bind_), binding_ (0, 0) { + // Here and below we want to maintain up to date binding info so + // that the call to parameters_binding() below is an immutable + // operation, provided the query does not have any by-reference + // parameters. This way a by-value-only query can be shared + // between multiple threads without the need for synchronization. + // + if (size_t n = bind_.size ()) + { + binding_.bind = &bind_[0]; + binding_.count = n; + binding_.version++; + } } query& query:: @@ -38,6 +50,11 @@ namespace odb clause_ = q.clause_; parameters_ = q.parameters_; bind_ = q.bind_; + + size_t n (bind_.size ()); + binding_.bind = n != 0 ? &bind_[0] : 0; + binding_.count = n; + binding_.version++; } return *this; @@ -54,12 +71,21 @@ namespace odb clause_ += q.clause_; + n = bind_.size (); + parameters_.insert ( parameters_.end (), q.parameters_.begin (), q.parameters_.end ()); bind_.insert ( bind_.end (), q.bind_.begin (), q.bind_.end ()); + if (n != bind_.size ()) + { + binding_.bind = &bind_[0]; + binding_.count = bind_.size (); + binding_.version++; + } + return *this; } @@ -75,9 +101,12 @@ namespace odb parameters_.push_back (p); bind_.push_back (MYSQL_BIND ()); + binding_.bind = &bind_[0]; + binding_.count = bind_.size (); + binding_.version++; + MYSQL_BIND* b (&bind_.back ()); memset (b, 0, sizeof (MYSQL_BIND)); - p->bind (b); } @@ -88,18 +117,10 @@ namespace odb binding& r (binding_); if (n == 0) - return r; // r.bind and r.count should be 0. - - MYSQL_BIND* b (&bind_[0]); + return r; bool inc_ver (false); - - if (r.bind != b || r.count != n) - { - r.bind = b; - r.count = n; - inc_ver = true; - } + MYSQL_BIND* b (&bind_[0]); for (size_t i (0); i < n; ++i) { |